TW202501598A - Substrate processing method and substrate processing device - Google Patents

Abstract

[Topic] Peripheral exposure that matches the state of the outer edge of the underlying film can be performed. [Solution] A substrate processing method according to one aspect of the present disclosure includes: a step of generating edge information indicating the relationship between the circumferential position around the center of the substrate and the outer edge position of the first coating in the radial direction of the substrate based on a photographic image obtained by photographing a peripheral area in the surface of the substrate on which the first coating is formed; a step of setting an exposure map indicating the relationship between the circumferential position and the set value of the exposure width in the radial direction based on the edge information; a step of forming a second coating in at least the peripheral area in the surface after obtaining the photographic image; and a step of exposing the second coating in the peripheral area based on the exposure map.

Description

Substrate processing method and substrate processing device

The present invention relates to a substrate processing method and a substrate processing device.

Patent document 1 discloses a substrate inspection device. The substrate inspection device includes an edge detection unit configured to detect a target edge, which is an edge of an inspection target coating, based on inspection image data obtained from a photographic image of a peripheral portion of a substrate on which a plurality of coatings are formed. [Prior art document] [Patent document]

[Patent Document 1] Japanese Patent Application Publication No. 2020-144102

[The problem that the invention wants to solve]

The present disclosure provides a substrate processing method and a substrate processing device capable of peripheral exposure in accordance with the state of the outer edge in the underlying film. [Means for solving the problem]

The substrate processing method according to one aspect of the present disclosure includes: a step of generating edge information indicating the relationship between the circumferential position around the center of the substrate and the outer edge position of the first coating in the radial direction of the substrate based on a photographic image obtained by photographing the peripheral area of the surface of the substrate on which the first coating is formed; a step of setting an exposure map indicating the relationship between the circumferential position and the set value of the exposure width in the radial direction based on the edge information; and a step of forming a second coating in at least the peripheral area of the surface after obtaining the photographic image; and a step of exposing the second coating in the peripheral area based on the exposure map. [Effect of the invention]

According to the present disclosure, a substrate processing method and a substrate processing apparatus are provided which are capable of peripheral exposure in accordance with the state of the outer edge in the underlying film.

Below, with reference to the drawings, an implementation is described. In the description, the same symbols are used for elements with the same elements or the same functions, and repeated descriptions are omitted. In some drawings, a rectangular coordinate system defined by the X-axis, Y-axis, and Z-axis is shown. In the following implementation, the X-axis and the Y-axis correspond to the horizontal direction, and the Z-axis corresponds to the up-down direction.

<Wafer processing system> First, the structure of the wafer processing system involved in this embodiment is described. FIG. 1 and FIG. 2 are schematic top view and front view respectively showing the outline of the structure of the wafer processing system 1. In this embodiment, the photolithography processing system in which the wafer processing system 1 (substrate processing device) performs photoresist film formation processing and imaging processing on the wafer W (substrate) is described as an example.

As shown in FIG. 1 , the wafer processing system 1 includes a cassette station 2 for carrying in and out cassettes C for accommodating a plurality of wafers W, and a processing station 3 equipped with a plurality of various processing devices for applying specific processing to the wafers W. Furthermore, the wafer processing system 1 has a structure in which the cassette station 2, the processing station 3, and an interface station 4 for receiving and delivering wafers W are connected to one another, as shown in FIG. 1 . In addition, although two processing stations 3 are provided between the cassette station 2 and the interface station 4 as shown in FIG. 1 , one or more than three processing stations may be provided.

A plurality of cassette stages 21, wafer transfer devices 22, and wafer transfer devices 23 are provided in the cassette station 2. In the cassette station 2, wafers W are transferred between the cassette C placed on the cassette stage 21 and the processing station 3 by the wafer transfer device 22 or the wafer transfer device 23. Therefore, each of the wafer transfer device 22 and the wafer transfer device 23 is provided with a driving mechanism for directions such as the X direction, the Y direction, the up-down direction, and around the vertical axis (θ direction) as required, and may be provided with a driving mechanism for all directions. At least one of the wafer transfer device 22 and the wafer transfer device 23 can transfer wafers W to and from the cassette C, and further, can transfer wafers W to and from the processing station 3. The wafer W is transferred between the processing stations 3 by, for example, a wafer transfer device 33 in the processing station 3 described later and a third block G3 having a transfer device capable of storing and receiving the wafer W. The third block G3 may have a plurality of transfer devices arranged in the vertical direction (not shown).

The inspection device U3 for inspecting the wafer W may be arranged at a position where either the wafer transport device 22 or the wafer transport device 23 can enter and exit. The inspection device U3 may be arranged in the cassette station 2 (for example, the third block G3). The inspection device U3 may be arranged in the processing station 3 instead of the cassette station 2 or in addition to the cassette station 2, or may be arranged in the interface station 4.

A plurality of blocks, such as the first block G1, the second block G2, and the fourth block G4, are provided in the processing station 3. Furthermore, as shown in FIG2, the layer 31 having the first block G1 and the second block G2 is stacked in the up-down direction in a plurality of stacked layers. For example, the first block G1 is provided on the front side (the negative side in the X direction of FIG1) of the processing station 3, and the second block G2 is provided on the back side (the positive side in the X direction of FIG1) of the processing station 3. The fourth block G4 is provided at the connection portion between the processing station 3 arranged on the side of the cassette station 2 (the negative side in the Y direction of FIG1) and the processing station 3 arranged on the side of the interface station 4 (the positive side in the Y direction of FIG1). The fourth block G4 may include a plurality of receiving and transmitting devices arranged in the vertical direction. Furthermore, the third block G3 may be disposed in the processing station 3.

A plurality of film processing devices U1 are arranged in the first block G1. The film processing device U1 is, for example, a pattern-forming film forming device or a developing device. As a pattern-forming film forming device, for example, in addition to a photoresist film forming device, a reflection prevention film forming device may be included. At least a part of the plurality of film processing devices U1 may be a device for performing film processing using a processing liquid. Film processing includes a step of forming a film and a step of performing a developing process.

In the first block G1, for example, a plurality of film processing devices U1 are arranged in a horizontal direction. The number, arrangement, and type of the film processing devices U1 can be arbitrarily selected.

In these patterning film forming devices or developing devices, for example, a step of supplying a specific processing liquid or a step of supplying a specific gas onto the wafer W is performed. In this way, in the patterning film forming device, a photoresist film used as a mask when forming a pattern of a film on the lower layer side is formed, or a reflection prevention film or the like is formed to efficiently perform a light irradiation process such as an exposure process. Furthermore, on the other hand, in the developing device, a part of the exposed photoresist film is removed to form a concave-convex shape as the above-mentioned mask.

For example, in the second block G2, a heat treatment device U2 for performing heat treatment such as heating or cooling of the wafer W is arranged in the vertical direction and the horizontal direction. Furthermore, in the second block G2, in order to improve the fixation of the photoresist liquid and the wafer W, a hydrophobic treatment device (not shown) for performing hydrophobic treatment and a peripheral exposure device U4 for exposing the outer periphery of the wafer W are arranged in the vertical direction (Z direction of FIG. 2 ) and the horizontal direction. Even the number or arrangement of these heat treatment devices, hydrophobic treatment devices, and peripheral exposure devices U4 can be arbitrarily selected. Even if the peripheral exposure device U4 is arranged at the interface station 4 instead of the processing station 3 (for example, the second block G2) or in addition to the processing station 3, it is also acceptable. Both the inspection device U3 and the peripheral exposure device U4 may be arranged in the processing station 3, or may be arranged in the interface station 4.

1 , a wafer transfer area 32 is formed in a region sandwiched between the first block G1 and the second block G2 in a plan view. In the wafer transfer area 32, for example, a wafer transfer device 33 is disposed.

The wafer transport device 33 has a transport arm that can move freely in the Y direction, the front-back direction, theta direction, and the up-down direction, for example. The wafer transport device 33 moves in the wafer transport area 32, and can transport the wafer W to specific devices in the surrounding first block G1, second block G2 or third block G3 and fourth block G4. As shown in FIG1, there are multiple processing stations 3. The wafer transport device 33 disposed in the processing station 3 located on the side of the interface station 4 can transport the wafer W to a specific device in the fifth block G5 described later in addition to the first block G1, the second block G2, and the fourth block G4.

The wafer transport device 33 is, for example, a plurality of stages arranged up and down. One wafer transport device 33 can transport the wafer W to a specific device at the height of the plurality of layers 31 located on the upper side among the plurality of layers 31 stacked up and down. Another wafer transport device 33 can transport the wafer W to a specific device at the height of the plurality of layers 31 located below the layers 31. A plurality of wafer transport areas 32 are arranged in such a manner that such transport of wafers W can be performed (refer to the areas arranged up and down in FIG. 2 ). In addition, a wafer transport device 33 is arranged in each layer 31, and the number of wafer transport devices 33 or the number of layers 31 corresponding to one wafer transport device 33 can be arbitrarily selected.

Furthermore, a shuttle transport device (not shown) may be provided in the wafer transport area 32, the first block G1, or the second block G2. The shuttle transport device linearly transports the wafer W between a space adjacent to one side of the processing station 3 and another space adjacent to the opposite side.

The interface station 4 is provided with a fifth block G5 having a plurality of receiving and sending devices, a wafer transport device 41, and a wafer transport device 42. The interface station 4 uses the wafer transport device 41 or the wafer transport device 42 to transport the wafer W between the fifth block G5 where the wafer transport device 33 receives and sends the wafer W and the exposure device. Therefore, each of the wafer transport device 41 and the wafer transport device 42 has a driving mechanism for directions such as the X direction, the Y direction, the up and down direction, and around the vertical axis (θ direction) as required, and may have a driving mechanism for all directions. At least one of the wafer transport device 41 and the wafer transport device 42 supports the wafer W and can transport the wafer W between the receiving and sending device and the exposure device in the fifth block G5.

Even the cleaning device for cleaning the surface of the wafer W, or the peripheral exposure device U4 mentioned above, may be installed in the interface station 4 at a position where at least one of the wafer transport device 41 and the wafer transport device 42 can enter and exit. In one example, in FIG. 1 , the cleaning device or the peripheral exposure device U4 may be installed in the interface station 4 at the four corners indicated by the dotted lines.

The above wafer processing system 1 is provided with a control device 100. The control device 100 is, for example, a computer, and has a program storage unit (not shown). The program storage unit stores a program for controlling the processing of the wafer W in the wafer processing device 1. Furthermore, the program storage unit also stores a program for controlling the operation of the drive system of the above-mentioned various processing devices or transport devices, etc., to realize the wafer processing in the wafer processing system 1. In addition, the above-mentioned program is recorded in a computer-readable storage medium H, and it is also possible to install it in the control device 100 from the storage medium H.

<Operation of wafer processing system> The wafer processing system 1 is configured as described above. Next, an example of wafer processing performed using the wafer processing system 1 configured as described above will be described.

First, a cassette C containing a plurality of wafers W is carried into the cassette station 2 of the substrate processing system 1 and placed on the cassette stage 21. Then, the wafers W in the cassette C are sequentially taken out by the wafer transfer device 22 or the wafer transfer device 23 and transferred to the receiving and delivering device of the third block G3.

The wafer W transported to the receiving and delivering device of the third block G3 is supported by the wafer transport device 33 and transported to the hydrophobic treatment device set in the second block G2 for hydrophobic treatment. Then, the wafer W is transported to the photoresist film forming device by the wafer transport device 33 to form a photoresist film on the wafer W, and then, after being transported to the heat treatment device for pre-baking treatment, it is transported to the receiving and delivering device of the fifth block G5. In addition, as shown in Figures 1 and 2, in the case of having multiple processing stations 3, the wafer W is temporarily placed in the receiving and delivering device of the fourth block G4 before being transported to the receiving and delivering device of the fifth block G5, and then is received and delivered between the multiple wafer transport devices 33. Furthermore, the wafer W is transported to the peripheral exposure device U4 by the wafer transport device 33, and the peripheral area of the wafer W is exposed.

The wafer W transferred to the receiving device of the fifth block G5 is transferred to the exposure device connected to the interface station 4 by the wafer transfer device 41 and the wafer transfer device 42, and is exposed in a specific pattern. In addition, the wafer W may be cleaned by the cleaning device before the exposure process.

The wafer W subjected to the exposure process is transported to the receiving and delivering device of the fifth block G5 by the wafer transport device 41 and the wafer transport device 42. Thereafter, it is transported to the thermal treatment device by the wafer transport device 33 to undergo a post-exposure baking process.

The wafer W that has been subjected to the post-exposure baking process is transported to the developing process device by the wafer transport device 33 and developed. After the development is completed, the wafer W is transported to the heat treatment device U2 by the wafer transport device 33 and subjected to the post-baking process.

Afterwards, the wafer W is transported to the receiving device of the third block G3 by the wafer transport device 33, and is transported to the cassette C of the specific cassette loading platform 21 by the wafer transport device 22 or the wafer transport device 23 of the cassette stage 2. In this way, a series of photolithography processes are completed. In addition, before or after exposure using the exposure device, a photoresist film is formed on at least the peripheral area of the wafer W, and after the photoresist film is exposed in the peripheral exposure device U4, it can be developed even in the development processing device.

<Liquid processing device> Next, referring to FIG. 3, a liquid processing device for forming a coating using a processing liquid is described by taking a film processing device U1 as an example. In this disclosure, a film of a processing liquid formed by applying a processing liquid and a film formed by heat treating a film of a processing liquid are collectively referred to as "coating". The film processing device U1 includes, for example, a rotation holding portion 45 and a liquid supply portion 50.

The rotation holding portion 45 includes a rotation driving portion 46, a rotating shaft 47, and a holding portion 48. The rotation driving portion 46 is operated according to an operation signal from the control device 100 to rotate the rotating shaft 47. The rotation driving portion 46 includes a power source such as an electric motor. The holding portion 48 is disposed at the front end of the rotating shaft 47. The wafer W can be placed on the holding portion 48. The holding portion 48 is configured to hold the wafer W in a substantially horizontal state, for example, by adsorption. That is, the holding portion 48 rotates the wafer W around a center axis (rotation axis) that is perpendicular to the surface Wa of the wafer W when the wafer W is in a substantially horizontal state.

The liquid supply unit 50 is configured to supply the processing liquid L to the surface Wa of the wafer W. The processing liquid L is, for example, a photoresist liquid for forming a photoresist film (hereinafter, referred to as "processing liquid Lr"). The photoresist material contained in the processing liquid Lr may be a positive photoresist material or a negative photoresist material. A positive photoresist material is a photoresist material that dissolves in exposed areas and remains in unexposed areas. A negative photoresist material is a photoresist material that dissolves in unexposed areas and remains in exposed areas. In the following, an example is given in which the processing liquid L is the processing liquid Lr and the photoresist material contained in the processing liquid Lr is a negative photoresist material.

The liquid supply unit 50 includes a liquid source 51, a pump 52, a valve body 53, a nozzle 54, a pipe 55, and a drive mechanism 56. The liquid source 51 functions as a supply source of the processing liquid Lr. The pump 52 operates according to an operation signal from the control device 100, sucks the processing liquid Lr from the liquid source 51, and delivers it to the valve body 54 through the pipe 55 and the valve body 53.

The nozzle 54 is arranged above the wafer W in such a manner that its discharge port faces the surface Wa of the wafer W. The nozzle 54 is configured to discharge the processing liquid Lr sent from the pump 52 to the surface Wa of the wafer W. The pipe 55 sequentially connects the liquid source 51, the pump 52, the valve body 53 and the nozzle 54 from the upstream side. The driving mechanism 56 is configured to operate according to the operation signal from the control device 100, so that the nozzle 54 moves in the horizontal direction and the vertical direction.

In the film processing apparatus U1, the wafer W on which the film of the processing liquid Lr is formed is transported to any heat processing apparatus U2, and the heat processing apparatus U2 performs heat processing on the wafer W. In this way, a photoresist film is formed on the surface Wa of the wafer W. As described above, the film processing apparatus U1 and the heat processing apparatus U2 may constitute a film forming section for forming a photoresist film as a kind of coating.

<Inspection device> Next, referring to FIG. 4 and FIG. 5, an example of the inspection device U3 is described. The inspection device U3 (inspection unit) is a device that generates one or more image data for inspecting the state of the wafer W. The inspection device U3 includes, for example, a frame 68, a rotation holding unit 60, a surface imaging unit 70, and a peripheral imaging unit 80. The rotation holding unit 60, the surface imaging unit 70, and the peripheral imaging unit 80 are arranged in the frame 68. A side wall in the frame 68 is formed with a loading and unloading port 69 for carrying the wafer W into the inside of the frame 68 and carrying the wafer W out of the frame 68.

The rotation holding unit 60 holds and rotates the wafer W, and moves the wafer W in the frame 68. The rotation holding unit 60 includes a holding table 61, drive mechanisms 62 and 63, and a guide rail 64. The holding table 61 is an adsorption fixture that holds the wafer W substantially horizontally by, for example, adsorption.

The driving mechanism 62 includes a power source such as an electric motor, which drives the holding table 61 to rotate. That is, the driving mechanism 62 rotates the wafer W held on the holding table 61. Even on the holding table 61, the wafer W can be mounted in a manner such that the center axis of rotation caused by the driving mechanism 62 is roughly consistent with the center of the wafer W. The driving mechanism 62 can also include an encoder for detecting the rotation position (rotation angle) of the holding table 61 around the above-mentioned center axis. In this case, the imaging position of the wafer W caused by the surface imaging unit 70 and the peripheral imaging unit 80 and the rotation position of the wafer W can be established in correspondence. In the case where the wafer W includes an indicator portion (e.g., a notch portion) indicating a reference position in the circumferential direction, the posture of the wafer W can be determined based on the indicator portion identified by the surface imaging unit 70 and the peripheral imaging unit 80, and the rotational position detected by the encoder.

The drive mechanism 63 is, for example, a linear actuator, and moves the holding table 61 along the guide rail 64. That is, the drive mechanism 63 transfers the wafer W held on the holding table 61 between one end side and the other end side of the guide rail 64. Therefore, the wafer W held on the holding table 61 can move between a first position near the loading and unloading port 69 and a second position near the peripheral imaging unit 80. The guide rail 64 extends linearly (for example, straightly) in the frame 68.

The surface imaging unit 70 includes a camera 71 and an illumination module 72. The camera 71 includes a lens and an imaging element (e.g., a CCD image sensor, a CMOS image sensor, etc.). The camera 71 is facing the illumination module 72 in the horizontal direction. That is, the camera 71 and the illumination module 72 are arranged in the horizontal direction.

The illumination module 72 includes a semi-mirror 73 and a light source 74. The semi-mirror 73 is arranged in the frame 68 at a slight inclination of 45° relative to the horizontal direction. The semi-mirror 73 is located above the middle part of the guide rail 64. The semi-mirror 73 is rectangular and extends in a manner intersecting the extension direction of the guide rail 64 when viewed from above. The length of the semi-mirror 73 is set to be greater than the diameter of the wafer W.

The light source 74 is located above the semi-mirror 73. The light emitted from the light source 74 passes through the semi-mirror 73 as a whole and is irradiated downward (toward the guide rail 64 side). The light passing through the semi-mirror 73 is reflected by an object located below the semi-mirror 73, and then reflected by the semi-mirror 73 again, and is incident on the imaging element of the camera 71 through the lens of the camera 71. That is, the camera 71 can photograph an object existing in the irradiation area of the light source 74 through the semi-mirror 73. For example, when the holding table 61 holding the wafer W is moved along the guide rail 64 by the driving mechanism 63, the camera 71 can photograph the surface Wa of the wafer W passing through the irradiation area of the light source 74. Image data captured by the camera 71 is sent to the control device 100.

The peripheral imaging unit 80 includes a camera 81, an illumination module 82, and a mirror component 83. The camera 81 includes a lens, an imaging element (e.g., a CCD image sensor, a CMOS image sensor, etc.). The camera 81 is facing the illumination module 82 in the horizontal direction. That is, the camera 81 and the illumination module 82 are arranged in the horizontal direction.

The illumination module 82 is arranged above the wafer W held on the holding table 61. The illumination module 82 includes a light source 84 and a semi-mirror 85. The semi-mirror 85 is arranged in a state of being tilted by about 45° relative to the horizontal direction as shown in FIG5. The mirror component 83 is arranged below the illumination module 82 as shown in FIG4 and FIG5. The mirror component 83 includes a body formed by an aluminum block and a reflecting surface.

The reflecting surface of the mirror component 83 faces the end surface Wb of the wafer W held on the holding table 61 and the peripheral area of the back surface of the wafer W when the wafer W held on the holding table 61 is located at the second position. The reflecting surface of the mirror component 83 is inclined with respect to the rotation axis of the holding table 61. The reflecting surface of the mirror component 83 is subjected to mirror processing. For example, a mirror sheet may be attached to the reflecting surface, and electroplating of aluminum may be performed, or aluminum material may be evaporated. The reflecting surface is a curved surface that is concave radially outward toward the wafer W held on the holding table 61.

In the illumination module 82, the light emitted from the light source 84 is entirely irradiated downward through the semi-mirror 85. A portion of the light that has passed through the semi-mirror 85 is reflected at the peripheral area of the surface Wa of the wafer W. The reflected light does not go toward the reflecting surface of the mirror member 83, but is further reflected by the semi-mirror 85 and then incident on the imaging element of the camera 81.

On the other hand, another part of the light passing through the semi-mirror 85 is reflected by the reflection surface of the mirror member 83 located below the semi-mirror 85. When the wafer W held on the holding table 61 is located at the second position, the reflected light reflected by the reflection surface of the mirror member 83 is mainly reflected by the end surface Wb of the wafer W. The reflected light is reflected by the reflection surface of the mirror member 83 and the semi-mirror 85 in sequence, and is incident on the imaging element of the camera 81.

In this way, the reflected light from the peripheral area in the surface Wa of the wafer W and the reflected light from the end surface Wb of the wafer W are incident on the imaging element of the camera 81 through different optical paths. That is, when the wafer W held on the holding table 61 is located at the second position, the camera 81 is configured to capture both the peripheral area of the surface Wa of the wafer W and the end surface Wb of the wafer W, and generate a captured image of the peripheral area of the surface Wa and a captured image of the end surface Wb. The captured image data captured by the camera 81 is sent to the control device 100. In addition, the inspection device U3 can photograph the peripheral area of the surface Wa, and can be constructed in any manner as long as a photographic image of the peripheral area can be generated. The peripheral area of the surface Wa can also be called a peripheral area in the surface Wa (peripheral area), which includes the periphery of the surface Wa and an annular area near the periphery. The peripheral imaging unit 80 can generate a photographic image of the end face Wb even if it does not photograph the peripheral area of the surface Wa. Even if the inspection device U3 is different from the peripheral imaging unit 80, it can have an imaging unit that can generate a photographic image of the end face Wb. The warp amount of the wafer W may be measured even from a photographic image of the end surface Wb that does not include the peripheral area of the surface Wa.

<Peripheral exposure device> Next, the peripheral exposure device U4 will be described with reference to FIG. 6(a) and FIG. 6(b). The peripheral exposure device U4 (peripheral exposure unit) is a device for exposing the peripheral area of the surface Wa of the wafer W. The peripheral exposure device U4 does not expose the area located further inside the peripheral area. The peripheral exposure device U4 has, for example, a rotation holding unit 110 and an exposure unit 120. The rotation holding unit 110 and the exposure unit 120 are arranged in a frame of the peripheral exposure device U4.

The rotation holding unit 110 is a unit that holds and rotates the wafer W. The rotation holding unit 110 includes a holding table 111 (holding portion), drive mechanisms 112 and 113, and a guide rail 114. The holding table 111 is an adsorption fixture that holds the wafer W substantially horizontally by, for example, adsorption.

The driving mechanism 112 includes a power source such as an electric motor, which drives the holding table 111 to rotate. That is, the driving mechanism 112 rotates the wafer W held on the holding table 111. The driving mechanism 112 may include an encoder for detecting the rotation position of the holding table 111. In this case, the exposure position of the wafer W caused by the exposure unit 120 and the rotation position of the wafer W can be established in correspondence. The holding table 111 holds the back side of the wafer W in a manner such that the rotation center of the wafer W caused by the driving mechanism 112 is roughly consistent with the center of the wafer W.

The driving mechanism 113 is, for example, a linear actuator, and moves the holding table 111 along the guide rail 114. That is, the driving mechanism 113 transports the wafer W held on the holding table 111 between one end side and the other end side of the guide rail 114. The guide rail 114 extends linearly (for example, straightly) within the frame of the peripheral exposure device U4, and one end thereof is located near the exposure unit 120. When the holding table 111 holding the wafer W is located at one end of the guide rail 114, the wafer W can be exposed even by the exposure unit 120.

The exposure unit 120 is a unit that irradiates the peripheral area of the surface Wa of the wafer W with exposure light. The exposure unit 120 irradiates the peripheral area of the surface Wa with exposure light while the wafer W held on the holding table 111 is rotating. The exposure unit 120 includes a light source 121, an optical system component 122, a mask component 123, and a drive mechanism 124. The light source 121 may be arranged vertically above the peripheral area of the surface Wa of the wafer W set at a position capable of exposure. The light source 121 irradiates energy rays (for example, ultraviolet rays) containing wavelength components capable of exposing the photoresist film toward the bottom. The light source 121 may be, for example, an ultra-high pressure UV lamp, a high pressure UV lamp, a low pressure UV lamp, or an excimer lamp.

The optical system component 122 is located below the light source 121. The optical system component 122 is composed of one or more lenses. The optical system component 122 converts the exposure light from the light source 121 into slightly parallel light and irradiates it to the mask component 123. The light source 121 and the optical system component 122 function as an irradiation unit for irradiating the exposure light. An opening 123a for adjusting the exposure area (exposure range) is formed in the mask component 123. The parallel light from the optical system component 122 passes through the opening 123a and irradiates the peripheral area of the surface Wa of the wafer W held on the holding table 111. When a developer is supplied to the photoresist film irradiated with the exposure light in the peripheral area, the area not irradiated with the exposure light is removed.

The driving mechanism 124 includes a power source such as an electric motor, and is connected to the mask member 123. The driving mechanism 124 is operated according to the operation signal from the control device 100, so that the mask member 123 moves along the radial direction of the wafer W. The radial direction of the wafer W is the radial direction of a circle around the center of the wafer W. The mask member 123 is moved along the above radial direction by the driving mechanism 124, and the radial size of the range where the exposure light reaches the portion of the peripheral area located in the photoresist film (hereinafter referred to as "exposure width") changes.

The mask member 123 is driven by the driving mechanism 124 in the radial direction within the range where the exposure light reaches the surface Wa, including the outer edge of the surface Wa. In this case, the exposure width is defined by the distance in the radial direction between the outer edge of the surface Wa and the most central part of the range where the exposure light reaches the surface Wa. Furthermore, in the radial direction, when the position of the mask member 123 relative to the center of the wafer W changes, the position in the radial direction of the most central part of the range where the exposure light reaches the surface Wa changes.

The method of changing the exposure width is not limited to the drive caused by the drive mechanism 124. The mask component 123 may have a baffle 125 as shown in Figure 6(b). In Figure 6(b), the cross section when the wafer W is cut along the radial direction is schematically omitted, and the optical system component 122 is omitted. The baffle 125 is a component that can adjust the opening 123a provided in the mask component 123. The opening 123a refers to the ratio of the area through which the exposure light from the light source 121 and the optical system component 122 passes, relative to the total area of the opening 123a.

The mask member 123 may be fixed at a position where the exposure light passing through the opening 123a reaches the outer edge of the surface Wa and the area inside the outer edge. The baffle 125 is connected to the driving part, and the baffle 125 can move in the radial direction. The baffle 125 can cover the area near the center of the wafer W in the opening 123a. The opening and closing degree of the opening 123a changes due to the radial position of the baffle 125, and as a result, the exposure width changes. That is, the radial position of the area closest to the center within the range where the exposure light reaches the surface Wa changes due to the radial position of the baffle 125.

The method of changing the exposure width is not limited to the drive mechanism 124 and the baffle 125. The peripheral exposure device U4 may change the exposure width by moving the holding table 111 holding the wafer W in the radial direction of the wafer W relative to the mask member 123. In this case, the mask member 123 may be fixed at a specific position. By moving the holding table 111 (wafer W) in the radial direction relative to the mask member 123, when observing the radial cross-section, the ratio of the area of the wafer W reached by the exposure light through the opening 123a and the area of the wafer W not reached by the exposure light changes. That is, the radial position of the wafer W relative to the mask member 123 changes within the range where the exposure light reaches the surface Wa, with the radial position of the portion closest to the center changing.

<Configuration of control device> FIG7 shows a block diagram of an example of the functional configuration of the control device 100. The control device 100 has, for example, an image information acquisition unit 201, an edge information generation unit 202, an exposure mapping setting unit 203, a mapping memory unit 204, a film formation control unit 205, an exposure control unit 206, and a result determination unit 207 as a functional configuration (hereinafter referred to as a "functional module"). The processing performed by these functional modules is equivalent to the processing performed by the control device 100.

The image information acquisition unit 201 is a functional module that acquires a photographic image obtained by photographing a peripheral area on the surface Wa of the wafer W in a state where a coating F1 (first coating) is formed on the surface Wa. Hereinafter, a photographic image obtained by photographing a peripheral area on the surface Wa in a state where a coating F1 (first coating) is formed on the surface Wa is referred to as a "peripheral photographic image" (also refer to FIG. 11(a)). The image information acquisition unit 201 acquires a peripheral photographic image, for example, from the inspection device U3. The coating F1 is a coating formed at least in the peripheral area under the photoresist film (hereinafter referred to as "coating F2"). The coating F1 may be any film among a plurality of layers of films formed under the coating F2. There may be other films between the coating F1 and the coating F2, and there may be no other films between the coating F1 and the coating F2 but the coating F2 may be formed on the coating F1.

The edge information generating unit 202 generates edge information representing the relationship between the circumferential position around the center of the wafer W and the outer edge position of the film F1 in the radial direction of the wafer W based on the peripheral photography image. The circumferential position is defined by, for example, the angle of an indicator portion (reference position) from the notch portion. The outer edge position of the film F1 is defined by, for example, the shortest distance along the radial direction between the center of the wafer W and the outer edge of the film F1. The outer edge of the film F1 is located further inward than the outer edge in the surface Wa of the wafer W. Therefore, the outer edge position of the film F1 is defined by the shortest distance along the radial direction between the logical position along the outer edge of the surface Wa and the outer edge of the film F1.

The edge information generating unit 202 may calculate the outer edge position of the film F1 for each specific angle in the circumferential direction when generating edge information. The edge information generating unit 202 calculates the outer edge position of the film F1 for each arbitrary angle (e.g., 1˚) between 0.5˚ and 5˚. The angle unit (e.g., 1˚) when calculating the outer edge position of the film F1 may also be referred to as the resolution of the edge information. This may be done even if the position of the indicator portion in the wafer W is set to 0˚. The edge information generating unit 202 may calculate the outer edge position of the film F1 from the peripheral photographic image by any imaging processing method.

The outer edge position of the coating F1 varies due to various main reasons, such as the circumferential position, that is, the angle from the indicator portion. In one example, a defective portion is formed at a portion of the outer edge of the coating F1, which is more recessed inward than the average outer edge position. The outer edge of the coating F1 may be an edge that is continuous as the circumferential position changes. That is, when the surface Wa is viewed from above, and the outer edge is observed along the circumferential direction from an arbitrary position in the outer edge of the coating F1 as a starting point, there is no discontinuous portion in the outer edge of the coating F1 (the outer edge of the coating F1 is continuous).

The exposure mapping setting unit 203 is a functional module that sets an exposure mapping that represents the relationship between the circumferential position around the center of the wafer W and the set value of the exposure width in the radial direction of the wafer W based on the above-mentioned edge information. The exposure mapping setting unit 203 may set the exposure width for each specific angle in the circumferential direction even in the exposure mapping. The exposure mapping setting unit 203 sets the exposure width for each arbitrary angle (e.g., 1˚) between 0.5˚ and 5˚. The angle unit (e.g., 1˚) when setting the exposure width may also be referred to as the resolution in the exposure mapping. The resolution in the above-mentioned edge information may be consistent with the resolution in the exposure mapping.

Even when the exposure map setting unit 203 sets the exposure map based on the edge information, the exposure map may be set in such a manner that the position of one end of the exposure range close to the center of the wafer W is offset by a certain value from the outer edge position of the film F1 indicated by the edge information for each specific angle (e.g., every 1°) in the circumferential direction. In this case, even if the circumferential position (angle) is different, the difference between the outer edge position of the film F1 in the edge information and the position close to one end of the wafer W in the exposure range becomes constant. The map storage unit 204 is a functional module that stores the exposure map set by the exposure map setting unit 203.

The film formation control unit 205 is a functional module that controls the film processing device U1 and the heat treatment device U2 in such a manner that the film F2 (second film) is formed on at least the peripheral region of the surface Wa after obtaining the peripheral photographic image. The film formation control unit 205 may control the film processing device U1 in such a manner that the film F2 is formed on the entire surface Wa, or may control the film processing device U1 in such a manner that the film F2 is formed on the peripheral region without forming the film F2 on the central portion including the center of the wafer W.

The exposure control unit 206 controls the functional module of the peripheral exposure device U4 so as to expose the film F2 in the peripheral area according to the exposure map stored in the map storage unit 204. The exposure control unit 206 controls the peripheral exposure device U4 so as to expose the film F2 with the exposure width set at the circumferential position according to the circumferential position.

The exposure control unit 206 may change the exposure width according to the circumferential position by moving the mask member 123 through the drive mechanism 124. The exposure control unit 206 may change the exposure width according to the circumferential position by changing the opening 123a of the mask member 123 through the movement of the baffle 125. The exposure control unit 206 may change the exposure width according to the circumferential position by moving the holding stage 11 holding the wafer W in the radial direction.

The result determination unit 207 is a functional module that determines whether the result of exposure according to the exposure map is normal. After developing the exposed coating F2, the result determination unit 207 uses a photographic image (hereinafter referred to as a "determination photographic image") obtained by photographing the peripheral area in the surface Wa to make a determination. The determination photographic image (the second photographic image) may be generated by the inspection device U3 or acquired by the image information acquisition unit 201. The peripheral photographic image and the determination photographic image may be acquired by the same inspection device U3 or by different inspection devices U3.

The result determination unit 207 generates the cutting information indicating the relationship between the circumferential position and the inner edge position of the film F2 (the annular film F2 after development) based on the determination of the photographic image. The inner edge position of the film F2 may be defined by the distance along the radial direction calculated from the logical position of the outer edge of the surface Wa. Since the film F2 is formed to the outer edge of the surface Wa, the inner edge position of the annular film F2 indicates the exposure width. The result determination unit 207 determines whether the exposure of the film F2 is normal based on the result of comparing the edge information and the exposure map with the cutting information.

<Hardware structure of control device> In FIG. 8, the hard disk structure of the control device 100 is illustrated. The control device 100 has, for example, a circuit 210. The circuit 210 has one or more processors 211, a memory 212, a storage 213, and an input/output port 214. The storage 213 has a storage medium such as a hard disk that can be read by a computer. The program for controlling the wafer processing system 1 is stored in the storage medium. That is, the storage 213 (or storage medium) functions as the above-mentioned program storage unit. Even if the storage medium is a non-volatile semiconductor memory, a removable medium such as a magnetic disk and an optical disk, it is also acceptable.

The memory 212 temporarily stores the program loaded from the storage medium of the storage 213 and the calculation results of the processor 211. The processor 211 executes the above program by cooperating with the memory 212 to form each functional module of the control device 100. The input/output port 214 performs input and output of electrical signals between the inspection device U3, the film treatment device U1, the heat treatment device U2, and the peripheral exposure device U4 according to the instructions from the processor 211.

In the case where the control device 100 is composed of a plurality of computers, each functional module may be implemented by an individual computer. Alternatively, each functional module may be implemented by a combination of two or more computers. In these cases, a plurality of computers may be connected to each other so as to be able to communicate with each other and to collaboratively implement control of the wafer processing system 1. In addition, the hardware configuration of the control device 100 is not necessarily limited to the configuration of each functional module by a program. For example, each functional module of the control device 100 may be configured by a dedicated logic circuit or an ASIC (Application Specific Integrated Circuit) that integrates the same.

[Substrate processing method] Next, an example of a substrate processing method implemented in the wafer processing system 1 is described with reference to FIGS. 9 to 14. In the following, a case where a film F2 as a photoresist film is formed on the peripheral area of a wafer W in a state where a film F1 as a base film has been formed with a concavo-convex pattern is described as an example. Under the film F1, a film F0 as another film may be formed as shown in FIG. 10(a) and the like.

The substrate processing method includes the steps of photographing a peripheral area on the surface Wa of a wafer W having a coating F1 formed on the surface Wa to obtain a peripheral photography image, and generating edge information representing the relationship between a circumferential position around the center of the wafer W and an outer edge position of the coating F1 in the radial direction of the wafer W based on the peripheral photography image. Furthermore, the substrate processing method further includes the step of setting an exposure mapping representing the relationship between the above-mentioned circumferential position and the set value of the exposure width in the radial direction of the wafer W according to the edge information, and the step of forming a film F2 in at least a peripheral area of the surface Wa after obtaining a peripheral photographic image, and the step of exposing the film F2 in the peripheral area according to the exposure mapping.

As shown in FIG. 9 , first, the control device 100 performs step S01. The control device 100 controls the wafer processing system 1 in a manner such as to form a film F1 on the surface Wa of the wafer W. Even if the film F1 is formed by the wafer processing system 1, the control device 100 may control the wafer processing system 1 in a manner such that the wafer W on which the film F1 is formed by another processing system is received. In the film F1 formed on the wafer W, the outer edge of the film F1 is removed in a manner such that the outer edge of the film F1 is located further inward than the outer edge of the surface Wa. Then, the wafer W on which the film F1 is formed on the surface Wa is transported to the inspection device U3.

Next, the control device 100 implements step S02. In step S02, for example, the image information acquisition unit 201 causes the inspection device U3 to photograph the peripheral area of the surface Wa of the wafer W on which the film F1 is formed, and acquires image data representing the peripheral photography image from the inspection device U3. FIG11(a) shows an example of the peripheral photography image. In addition, in the peripheral photography image shown in FIG11(a), the circumferential direction position is converted into the horizontal direction on the image, and the radial direction is converted into the vertical direction on the image.

Next, the control device 100 executes step S03. In step S03, for example, the edge information generating unit 202 generates edge information (edge profile) indicating the relationship between the circumferential position and the outer edge position of the film F1 in the radial direction from the image data obtained in step S01. The edge information generating unit 202 may calculate the outer edge position of the film F1 in the radial direction from the image data obtained in step S01 for each specific angle (for example, every 1°) even near the center of the wafer W.

FIG11(b) is a graph showing an example of edge information. In FIG11(b), "Xθ(˚)" as the horizontal axis of the graph represents the circumferential position (or angle) around the center of the wafer W. "Xr(mm)" as the vertical axis of the graph represents the radial position from the center of the wafer W. "Eo" represents the logical radial position of the outer edge of the surface Wa of the wafer W, and "R" represents the value obtained by subtracting a specific value from Eo. Eo is taken as an example of 150 mm, and R is an arbitrary value between 140 mm and 148 mm. "E1" is information representing the calculated result of the radial position (outer edge position) of the outer edge of the film F1.

In the edge information, for example, the outer edge position E1 is obtained by calculating the outer edge position of the film F1 at each circumferential position while changing the circumferential position Xθ by 1°. The edge information generating unit 202 may calculate the outer edge position of the film F1 from the difference in pixel values between adjacent pixels on the image, for example. The edge information generating unit 202 establishes a correspondence between the circumferential position and the outer edge position of the film F1 by defining the position of the indicator portion of the wafer W formed on the image.

Next, the control device 100 implements step S04. In step S04, for example, the exposure map setting unit 203 sets an exposure map representing the relationship between the circumferential position Xθ around the center of the wafer W and the set value of the exposure width in the radial direction of the wafer W based on the edge information generated in step S03. The set exposure map is stored by the map storage unit 204. The exposure map setting unit 203 may set the exposure width by setting the position of one end of the exposure range close to the center of the wafer W for each specific angle (for example, every 1˚) around the center of the wafer W. By passing through the center of the wafer W close to the exposure range, the position of one end changes, the distance between the position of the one end and the outer edge Eo of the surface Wa changes, and the exposure width changes.

The exposure mapping setting unit 203 may set the position of one end of the exposure range close to the center of the wafer W for each specific angle in a manner along the shape of the outer edge position E1 represented by the edge information. FIG. 12(a) visualizes and represents an example of the setting of the exposure mapping. FIG. 12(a) shows a curve diagram of the position of one end of the exposure range close to the center of the wafer W relative to the change in the circumferential position. The distance between the position of one end of the exposure range close to the center of the wafer W and the outer edge Eo of the surface Wa is the exposure width, and "Ees" is information representing the setting value of the exposure width corresponding to the circumferential position.

The exposure map setting unit 203 sets the exposure map (exposure width Ees) in accordance with the change inclination of the circumferential position of the exposure width, along the change inclination of the circumferential position of the outer edge of the film F1 indicated by the edge information. For example, the exposure map setting unit 203 sets the exposure map in such a way that even at any circumferential position Xθ, one end of the exposure range close to the center of the wafer W is located further inward than the outer edge of the film F1, and the difference between the one end and the outer edge of the film F1 is less than a specific value. The above setting value may be about 0.5 mm to 3 mm, or about 0.5 mm to 2 mm.

By setting the exposure map, the exposure width is set to a different value according to the circumferential position Xθ in accordance with the shape of the outer edge of the film F1 formed below the film F2. In the example shown in FIG. 12(a), the exposure width is set to "w1" in a certain range of the circumferential position Xθ, the exposure width is set to "w2" in another certain range, and the exposure width is set to "w3" in another certain range. In addition, even between two exposure widths among w1, w2, and w3 (for example, during the period of change from w1 to w2), the exposure width is set in accordance with the change of the outer edge of the film F1.

Fig. 12(b) schematically shows the relationship between the annular film F2 after exposure and development and the film F1. By setting the exposure width Ees along the outer edge of the film F1, as shown in Fig. 12(b), the annular film F2 after exposure and development is formed to cover the entire outer edge of the film F1, and the inner edge shape of the film F2 is formed along the outer edge of the film F1.

FIG. 13 shows an example different from FIG. 11(b) and FIG. 12(a) for the calculation result of the outer edge position of the film F1 (outer edge position E1) and the setting result of the exposure width in the exposure mapping (exposure width Ees). Unlike FIG. 11(b) and FIG. 12(a), in FIG. 13, the vertical axis represents the radial distance from the outer edge Eo of the surface Wa. As shown in FIG. 13, the exposure mapping setting unit 203 may set the exposure width in such a manner that the position of one end of the exposure range close to the center of the wafer W is offset by a certain value from the outer edge position of the film F1 represented by the edge information for each specific angle (for example, every 1°). In this case, the difference between the exposure width Ees and the outer edge position E1 is constant even at any circumferential position Xθ. In other words, the exposure width Ees is offset from the outer edge position E1 by a constant value in the entire range of 0° to 360° around the center of the wafer W. The constant offset value may be about 0.5mm to 5.0mm, or about 0.5mm to 3.0mm.

Table 1 below shows an example of exposure mapping for a case where the exposure width is set every 1˚. The exposure mapping shown in Table 1 is provided for easy understanding of the contents of this disclosure.

Returning to FIG. 9 , the control device 100 then executes step S05. Before the execution of step S05, the wafer W in the state of forming the coating F1 is transported from the inspection device U3 to the film processing device U1. In step S05, for example, the film formation control unit 205 controls the film processing device U1 in a manner of coating the processing liquid Lr on the entire surface Wa of the wafer W as shown in FIG. 10(a). Furthermore, after the wafer W is transported to the heat treatment device U2, the film formation control unit 205 controls the heat treatment device U2 in a manner of coating the film by heating the processing liquid Lr as shown in FIG. 10(b). In this way, the coating F2 before exposure and development is formed on the entire surface Wa. Afterwards, the wafer W is transported from the thermal treatment device U2 to the peripheral exposure device U4.

Next, the control device 100 implements step S06. In step S06, for example, the exposure control unit 206 controls the peripheral exposure device U4 so as to expose the film F2 in the peripheral area of the surface Wa according to the exposure map set in step S04. As shown in FIG. 10(c), the exposure control unit 206 rotates the wafer W held on the holding table 111 by the rotating holding unit 110, and irradiates the outer peripheral area of the surface Wa with exposure light by the exposure unit 120. The exposure control unit 206 controls the peripheral exposure device U4 so as to expose the film F2 with the set exposure width for each angle of the exposure width set by the exposure map.

When using the example shown in Table 1, the exposure control unit 206 controls the peripheral exposure device U4 so that, for example, the exposure width becomes 1.1 mm when the circumferential position Xθ is 1°, and the exposure width becomes 1.2 mm when the circumferential position Xθ is 2°. The exposure control unit 206 may continue to irradiate the exposure light from the exposure unit 120 while the rotation of the wafer W is not stopped. In this case, during the period when the circumferential position Xθ moves from 1° to 2°, the exposure control unit 206 moves the mask member 123 by the drive mechanism 124 so that the exposure width changes from 1.1 mm to 1.2 mm. The exposure control unit 206 may change the speed of the mask member 123 in response to the change in exposure width even between two consecutive steps of the exposure mapping. After the peripheral area of the film F2 is exposed according to the exposure mapping, the wafer W is transferred from the peripheral exposure device U4 to the thermal treatment device U2.

Next, the control device 100 performs step S07. In step S07, for example, the film formation control unit 205 controls the heat treatment device U2 to perform a pre-development heat treatment on the wafer W (film F2) as shown in FIG. 10( d ). After the pre-development heat treatment, the wafer W is transported from the heat treatment device U2 to the film treatment device U1 for the development process.

Furthermore, the film formation control unit 205 controls the film processing device U1 in such a manner that the developer Ld is supplied to the surface Wa to develop the coating F2 as shown in FIG10(e). Thus, the coating F2 that is not irradiated with the exposure light is removed. Thereafter, by rinsing the developer Ld, a ring-shaped coating F2 is formed on the outer peripheral area of the surface Wa as shown in FIG10(f). The wafer W after development is transported from the film processing device U1 to the inspection device U3.

Next, the control device 100 implements step S08. In step S08, for example, the result determination unit 207 performs inspection processing related to exposure of the film F2. In one example, the result determination unit 207 obtains image data for inspection processing (the above-mentioned determination image) from the inspection device U3 by photographing the peripheral area of the wafer W after exposure and development by the inspection device U3. The result determination unit 207 generates cutting information on the relationship between the circumferential position Xθ and the inner edge position of the film F2 in the radial direction of the wafer W from the image data for inspection processing. The result determination unit 207 may calculate the inner edge position of the film F2 in the radial direction of the wafer W from the image data for inspection processing for each specific angle (for example, each 1°) around the center of the wafer W.

FIG. 14( a) is a graph showing an example of cutting information. In FIG. 14( a), the vertical axis represents the radial distance between the outer edge Eo of the surface Wa and the inner edge position of the film F2, that is, the radial width of the film F2. "Eer" is information showing the result of calculating the radial position (inner edge position) of the inner edge of the film F2. If the peripheral exposure according to the exposure mapping is normal, the inner edge position Eer is roughly consistent with the exposure width Ees shown in FIG. 13, or is offset by a specific value at any circumferential position Xθ from the outer edge position E1 related to the film F1. Therefore, the result determination unit 207 can determine whether the result of the peripheral exposure is normal by comparing the exposure width Ees and the inner edge position Eer. Furthermore, the result determination unit 207 can determine whether the result of the peripheral exposure is normal by comparing the outer edge position E1 and the inner edge position Eer.

In one example, the result determination unit 207 calculates the difference between the inner edge position Eer and the outer edge position E1 for each specific angle (e.g., every 1°) around the center of the wafer W. FIG. 14(b) is a graph showing the difference obtained by subtracting the outer edge position E1 from the inner edge position Eer. When a constant value offset from the outer edge position E1 is set to "OS", if the peripheral exposure is normal, the difference between the inner edge position Eer and the outer edge position E1 becomes approximately constant regardless of the circumferential direction position Xθ.

On the other hand, due to some factors, an abnormality occurs somewhere, such as the portion indicated by "A" in FIG. 14(b), and the difference between the inner edge position Eer and the outer edge position E1 deviates from the offset constant value (OS). In this case, the result determination unit 207 can determine that the exposure is not performed normally in the portion indicated by "A". In addition, by observing the difference between the outer edge position E1 (measured value) and the inner edge position Eer (measured value) instead of the difference between the exposure width Ees (set value) and the inner edge position Eer (measured value), it is also possible to confirm whether the inner edge position of the film F2 is offset.

The control device 100 also performs a series of processing of steps S01 to S08 for each of the subsequent plurality of wafers W. For each wafer W, the shape (state) of the outer edge of the film F1 is likely to be different. By repeating the above series of processing, an exposure map suitable for each wafer W can be set.

[Variation] The series of processing shown in FIG. 9 is an example and can be modified appropriately. In the above series of processing, the control device 100 may perform a step and the next step in parallel, or may perform each step in a different order from the above example. The control device 100 may perform steps with contents different from the above example.

In the above example, although the processing liquid Lr is applied to the entire surface Wa when forming the coating F2 before exposure and development, the processing liquid Lr may not be applied to the central portion of the surface Wa. In FIG. 15(a) to FIG. 15(f), a substrate processing method is shown in which a coating film of the processing liquid Lr is formed only on the peripheral area of the surface Wa. The processes shown in FIG. 15(a), FIG. 15(b), FIG. 15(c), FIG. 15(d), FIG. 15(e), and FIG. 15(f) correspond to the processes shown in FIG. 10(a), FIG. 10(b), FIG. 10(c), FIG. 10(d), FIG. 10(e), and FIG. 10(f), respectively.

As shown in FIG. 15( c ), an annular coating F2 is formed in the peripheral area of the surface Wa and its vicinity. The inner edge of the coating F2 is formed to be located further inward than the outer edge of the coating F1. Furthermore, the coating F2 is subjected to peripheral exposure by a peripheral exposure device U4 having an exposure unit 120. By exposing and developing the coating F2, the unexposed portion (a portion located on the inner side) of the annular coating F2 is removed. In addition, in the heat treatment shown in FIG. 15( b ) and FIG. 15( d ), heat may be applied to the peripheral area of the wafer W instead of the central portion of the wafer W.

As shown in FIG. 16(a), the coating F2 before exposure and development may be formed to cover not only the surface Wa of the wafer W but also the end surface Wb. The peripheral exposure device U4 may have an exposure unit 130 capable of exposing the end surface Wb in addition to the exposure unit 120. FIG. 16(b) schematically shows the coating F2 on the end surface Wb before exposure and development, and FIG. 16(c) schematically shows the coating F2 on the end surface Wb after exposure and development. FIG. 16(d) schematically shows the coating F2 after exposure and development. As shown in FIG. 16(c) and FIG. 16(d), a portion of the coating F2 may be removed by exposure and development at the lower part of the end surface Wb.

As described above, in the inspection device U3, in addition to the peripheral area of the surface Wa, the photographic image of the end surface Wb can also be obtained. Therefore, the control device 100 can detect the state of the base at the end surface Wb from the photographic image of the end surface Wb. Moreover, the exposure control unit 206 can perform exposure on the end surface Wb by the exposure unit 130 in accordance with the state of the base at the end surface Wb. For example, the height of the area irradiated with the exposure light from the exposure unit 130 can be adjusted according to the circumferential direction position Xθ in accordance with the state of the base at the end surface Wb.

In the above example, the inner edge of the film F2 after exposure and development is located inside the outer edge of the film F1, and the film F2 is formed along the shape of the outer edge of the film F1. Even differently, the inner edge of the film F2 after exposure and development is located outside the outer edge of the film F1, and the film F2 is formed along the shape of the outer edge of the film F1.

In the above example, although a negative photoresist material is used, the coating F2 can be formed even if a positive photoresist material is used. In this case, for example, the coating F2 before exposure and development is formed on the entire surface Wa, and then the peripheral area of the coating F2 is exposed by the peripheral exposure device U4 with an exposure width corresponding to the position of the outer edge of the coating F1. Moreover, since the exposed area is removed by development, the peripheral area of the coating F2 is removed. If the outer edge of the coating F2 after exposure and development follows the shape of the outer edge of the coating F1, it can be located outside the outer edge of the coating F1 or inside the outer edge of the coating F1.

In the case of using a positive photoresist material, the result determination unit 207 generates cutting information indicating the relationship between the circumferential position and the outer edge position of the film F2 (the film F2 after the peripheral portion is removed after development) based on the determination of the photographic image. The outer edge position of the film F2 may be defined by the distance along the radial direction calculated from the logical position of the outer edge of the surface Wa. In the film F2 before development and exposure, since it is exposed to the outer edge of the surface Wa, the outer edge position of the film F2 after the peripheral portion is removed represents the exposure width. The result determination unit 207 is the same as the case of using a negative photoresist material, and determines whether the exposure of the film F2 is normal based on the result of comparing either the edge information or the exposure mapping and the cutting information.

The image information acquisition unit 201 may obtain the peripheral photographic image of the peripheral area in the surface Wa from an external device different from the substrate processing system instead of the inspection device U3.

Even when the exposure width is changed by driving the mask member 123 according to the exposure mapping, the exposure control unit 206 can change the exposure width while the rotation of the wafer W is stopped by the driving mechanism 112 of the rotation holding unit 110. For example, when the exposure mapping shown in Table 1 is obtained, the exposure control unit 206 can control the peripheral exposure device U4 so that the exposure width (1.1 mm) corresponding to 1˚ is established in the range of the circumferential position Xθ (angle) of 1˚ to 2˚. Moreover, the exposure control unit 206 can stop the rotation of the wafer W before being irradiated with the exposure light at the circumferential position Xθ of 2˚, and change the position of the mask member 123, etc., in accordance with the exposure width (1.2 mm) corresponding to 2˚.

The exposure mapping may be set as shown in Table 2 below.

The exposure mapping shown in Table 2 represents the processing from "Step 1" to "Step 359" that is performed in sequence. As conditions for each Step, the processing time (seconds), exposure width (mm), start angle (˚), and angle range (˚) are set. The processing time represents the execution time of the Step, and the exposure width is the radial exposure range set according to the edge information. The start angle represents the circumferential position Xθ (angle) for executing the Step, and the angle range represents the circumferential range for continuing the Step. For example, in Step 1, it refers to the processing that continues for only 0.5 seconds in a state where the circumferential position Xθ is adjusted from 0˚ to 1˚ to an exposure width of 1.1 mm. The following describes several examples of control based on the exposure mapping shown in Table 2.

(Example 1) The exposure control unit 206 may change the exposure width by driving the mask member 123 while maintaining the rotation of the wafer W, even if the exposure width has been changed since the previous Step. When the exposure control unit 206 starts the current Step, it may start driving the mask member 123 for changing the exposure width. Driving the mask member 123 means driving the mask member 123 for changing the exposure width, driving the baffle 125 for changing the exposure width, or driving the holding table 111 for changing the exposure width. The exposure control unit 206 may control the drive mechanism 112 for rotationally driving the holding table 111 in all steps so as to rotate the wafer W at a certain rotation speed. In all steps, exposure light having a certain illumination may be irradiated to the exposure position on the surface Wa of the wafer W by the exposure unit 120.

(Example 2) In the exposure mapping, the exposure width and the rotation speed of the wafer W may be set for each specific angle. When exposing the film F2, the exposure control unit 206 may irradiate the surface Wa with exposure light by the exposure unit 120 while changing the exposure width while continuing to rotate the wafer W according to the exposure mapping. In setting the exposure mapping, the exposure mapping setting unit 203 may repeatedly evaluate the difference in exposure width between two consecutive angles while changing the angles one by one. Here, one of the two angles to be evaluated that is initially irradiated with exposure light is set as the "first angle", and the other angle that is continuous with the first angle is set as the "second angle". The exposure map setting unit 203 may repeatedly calculate the difference between the exposure width at the first angle and the exposure width at the second angle continuous to the first angle while changing the second angle one by one at the above-mentioned specific angle. Furthermore, the exposure map setting unit 203 may set the rotation speed in the range to a value greater than the speed reference value when the above-mentioned difference (the difference in exposure width between the first angle and the second angle) is less than the condition of the specific standard and the range including the continuous angles of more than the specific number is satisfied. Each of the specific standard and the specific number is arbitrarily set in advance at the time of setting the exposure map.

In one example, after creating an exposure map like Table 2, the exposure map setting unit 203 repeatedly calculates the difference between the exposure width at the target Step (exposure width at the second angle) and the exposure width at the step preceding the target Step (exposure width at the first angle) while increasing the target Step one by one. Specifically, the exposure map setting unit 203 calculates the difference between the exposure width at Step 1 and the exposure width at Step 2, and then calculates the difference between the exposure width at Step 2 and the exposure width at Step 3. Thereafter, the exposure map setting unit 203 similarly repeats the difference between the exposure widths of two consecutive Steps.

The exposure mapping setting unit 203 sets the rotation speed to a value greater than the speed reference value in the range including the specific number of consecutive Steps (for example, 3 to 7) when the condition that the difference in exposure width between two consecutive Steps is less than a specific standard is satisfied. When explaining using a specific example, when the above-mentioned specific number is assumed to be 5, the difference in exposure width from the previous Step is within a specific standard (for example, ±0.3mm) in the range of Step 2 to 6, and the difference in exposure width between Step 6 and Step 7 is greater than the specific standard. In this case, the exposure mapping setting unit 203 sets the rotation speed to a value greater than the speed reference value (for example, 12rpm) in the range of Step 2 to 6. Furthermore, when the specific number is 5, if the above conditions are met with 6 or more consecutive steps, the rotation speed is set to a value greater than the speed reference value in the 6 or more steps.

The exposure map setting unit 203 may set the rotation speed to the speed reference value (or less than the speed reference value) even in the step (angle) outside the range where the rotation speed is set to a value greater than the speed reference value. Depending on the setting of the exposure width in the exposure map, there may not be a continuous number of steps that meet the above conditions. In this case, the exposure map setting unit 203 may set the rotation speed to the speed reference value (or less than the speed reference value) in each of all the steps.

(Example 3) As in Example 2 above, when the exposure width is changed continuously and the rotation speed is increased within a relatively small range, the illumination of the exposure light may be further set for each specific angle in the exposure mapping. The exposure control section 206 may control the exposure unit 120 in such a manner that the exposure light is irradiated to the surface Wa while adjusting the illumination according to the exposure mapping when exposing the film F2. In this case, the exposure unit 120 may be configured to be able to adjust the illumination of the exposure light (the amount of doping in the area irradiated with the exposure light). The amount of doping in the area irradiated with the exposure light on the surface Wa changes according to the illumination of the exposure light.

The exposure mapping setting unit 203 may set the illumination of the exposure light to a value greater than the illumination reference value even when the rotation speed of the wafer W is set to a value greater than the speed reference value when setting the exposure mapping. To explain using a specific example, in the exposure mapping shown in Table 2, in the range of Step 2 to 6, when the rotation speed is set to a value greater than the speed reference value, the illumination of each of Step 2 to 6 is set to a value greater than the illumination reference value. When the above conditions are met and there are no continuous steps greater than a specific number, the exposure mapping setting unit 203 may set the illumination of the exposure light to the illumination reference value (or less than the illumination reference value) in each of all the steps.

(Example 4) In addition to or instead of the setting of Example 2, the exposure map setting unit 203 may set the rotation speed at the angle (second angle) where the difference between the exposure width satisfying the first angle and the exposure width at the second angle following the first angle is greater than the specific level to a value smaller than the speed reference value. In Example 4, the exposure map setting unit 203 may repeatedly calculate the difference between the exposure width at the first angle and the exposure width at the second angle following the first angle while changing the second angle by the specific angle. The specific level used in Example 4 may be different from the specific level used in Example 2 and may be arbitrarily set in advance at the time of setting the exposure map.

In one example, after creating the exposure map as shown in Table 2, the exposure map setting unit 203 repeatedly calculates the difference between the exposure width of the target step (exposure width at the second angle) and the exposure width of the step preceding the target step (exposure width at the first angle) while increasing the target step one by one. Furthermore, the exposure map setting unit 203 sets the rotation speed to a value smaller than the speed reference value for the target step that satisfies the condition that the difference in exposure width between two consecutive steps is greater than a specific calibration.

When explaining using a specific example, in Step 5, it is assumed that the difference in exposure width from Step 4, which is the previous Step, is greater than a specific standard (for example, ±0.5 mm). In this case, the exposure mapping setting unit 203 sets the rotation speed to a value (for example, 5 rpm) smaller than the speed reference value (for example, 10 rpm) within the range of Step 5. The exposure mapping setting unit 203 may set the rotation speed to the speed reference value (or higher than the speed reference value) even in a Step (angle) outside the range where the rotation speed is set to a value smaller than the speed reference value. Depending on the setting of the exposure width in the exposure mapping, there may be a case where there is no Step that satisfies the above condition in Example 4. In this case, the exposure mapping setting unit 203 may set the rotation speed to the speed reference value (or higher than the speed reference value) in each of all the Steps.

(Example 5) As in Example 4, when the rotation speed is reduced in the portion where the exposure width changes rapidly, the illumination of the exposure light may be further set for each specific angle in the exposure map. The exposure control section 206 may control the exposure unit 120 so that the surface Wa is irradiated with the exposure light while adjusting the illumination according to the exposure map when exposing the film F2. In this case, the exposure unit 120 may be configured to be able to adjust the illumination of the exposure light (the doping amount in the area irradiated with the exposure light).

The exposure mapping setting unit 203 may set the illuminance of the exposure light to a value smaller than the illuminance reference value even when the rotation speed of the wafer W is set to one or more angles smaller than the speed reference value when setting the exposure mapping. When using a specific example to illustrate, in the exposure mapping shown in Table 2, in the range of Step 5, when the rotation speed is set to a value smaller than the speed reference value, the illuminance of Step 5 is set to a value smaller than the illuminance reference value. In the case where there is no Step that satisfies the above conditions in Example 4, the exposure mapping setting unit 203 may set the illuminance of the exposure light to the illuminance reference value (or above the illuminance reference value) in each of all the Steps.

(Example 6) Even in response to the warp state in the surface Wa of the wafer W, it is possible to perform peripheral exposure in the surface Wa while adjusting the position of the mask member 123 in the direction in which the exposure light is emitted. FIG17(a) shows a schematic diagram for illustrating the subject of a situation in which the wafer W contains warp. In FIG17(a), a wafer W that is not warped (flat) at the exposure target in the peripheral area is represented by "W1", a wafer W that is warped in a manner that the exposure target in the peripheral area is warped upward is represented by "W2", and a wafer W that is warped in a manner that the exposure target in the peripheral area is warped downward is represented by "W3". In addition, in one wafer W, two or more characteristics of a portion without warp, a portion warped upward, and a portion warped downward may coexist.

In FIG. 17( a ), the area marked with the majority of dots represents the range of light irradiated from the opening of the mask member 123. Even if the light path is adjusted by the optical system member 122, the range of light irradiated from the opening of the mask member 123 becomes wider as the light travels. When the position of the mask member 123 is fixed, the distance in the Z-axis direction between the mask member 123 and the exposure object of the surface Wa (hereinafter referred to as "irradiation distance Id", refer to FIG. 17( b)) is different among wafers W1, W2, and W3. When the irradiation distances Id are different from each other, the width actually exposed changes even if the setting value of the exposure width is the same.

As shown in FIG. 7 , the control device 100 may include a warp information acquisition unit 209 as a functional block. The warp information acquisition unit 209 acquires information indicating the state of warp in the peripheral region of the surface Wa of the wafer W (hereinafter referred to as “warp information”). The warp information acquisition unit 209 acquires, for example, an end face image of the end face Wb of the wafer W photographed from the inspection device U3, and acquires the warp information from the difference with a reference wafer without warp. The warp information may be information indicating the relationship between the circumferential position Xθ around the center of the wafer W and the warp amount of the outer edge portion of the surface Wa of the wafer W.

The warp information acquisition unit 209 may calculate the warp amount of the outer edge portion of the surface Wa for each specific angle in the circumferential direction when generating the warp information. The warp information acquisition unit 209 calculates the warp amount of the outer edge portion of the surface Wa for each arbitrary angle (e.g., 1˚) between 0.5˚ and 5˚. The angle unit (e.g., 1˚) when calculating the warp amount of the outer edge portion of the surface Wa may also be referred to as the resolution of the warp information. The resolution of the warp information may be the same as the resolution of the exposure mapping.

The driving mechanism 124 connected to the mask member 123 may change the position of the mask member 123 in the Z-axis direction. In addition, the mask member 123 having the baffle 125 may be raised and lowered by the driving mechanism connected to the mask member 123. In the exposure mapping, the position of the mask member 123 in the direction in which the exposure light is emitted may be set for each specific angle. The exposure control section 206 may control the exposure unit 120 (for example, the driving mechanism 124) in such a manner that the exposure light is irradiated onto the surface Wa while adjusting the position of the mask member 123 in the direction in which the exposure light is emitted according to the exposure mapping. The direction in which the exposure light from the opening 123a of the mask member 123 is emitted may be the Z-axis direction. That is, the opening 123a (the plane including the opening edge of the opening 123a) may be perpendicular to the Z-axis direction.

In setting the exposure map, the exposure map setting unit 203 may set the position of the mask member 123 in the direction in which the exposure light is emitted for each specific angle based on the warp information. The exposure map setting unit 203 may set the position of the mask member 123 in the Z-axis direction in such a manner that the difference in the irradiation distance Id for each angle is reduced according to the amount indicated by the warp information (for example, such a manner that the irradiation distance Id becomes constant). The position of the mask member 123 in the Z-axis direction may be defined by the difference from the reference position (that is, the offset value).

As shown in FIG. 17( b ), the peripheral exposure device U4 may include a position sensor 132 and a position sensor 134. The position sensor 132 is a sensor that obtains information indicating the position of the mask member 123 in the Z-axis direction. The position sensor 132 is a sensor that obtains information indicating, for example, the position in the Z-axis direction below the mask member 123. The position sensor 134 is a sensor that obtains the position in the Z-axis direction of the peripheral portion (exposure object) of the surface Wa of the wafer W. The irradiation distance Id can be calculated using the position information obtained by the position sensor 132 and the position sensor 134. If the position sensor 132 and the position sensor 134 can detect information indicating a position, any type of sensor may be used, but for example, a non-contact position sensor may be used.

The control device 100 may obtain information from the position sensors 132 and 134 while controlling the peripheral exposure device U4 so as to expose the film F2 in the peripheral area of the surface Wa according to the exposure map. Furthermore, the control device 100 may evaluate whether the irradiation distance Id during the exposure of the film F2 in the peripheral area is within an appropriate range based on the information from the position sensors 132 and 134. The control device 100 may issue an alarm even if it is evaluated that the irradiation distance Id during the exposure is not within an appropriate range.

When comparing the magnitude of two numerical values in a computer, either of the two criteria such as "above" and "greater" may be used, or either of the two criteria such as "below" and "less than" may be used. The selection of such a criterion does not change the technical significance of the process for comparing the magnitude of two numerical values. In one of the various examples described above, at least a part of the matters described in other examples may be combined.

[Summary of the present disclosure] [1] A substrate processing method, comprising the steps of obtaining a peripheral photographic image by photographing a peripheral area on a surface Wa of a wafer W having a coating F1 formed on the surface Wa, generating edge information indicating the relationship between a circumferential position Xθ around the center of the wafer W and an outer edge position of the coating F1 in the radial direction of the wafer W; setting an exposure mapping indicating the relationship between the circumferential position Xθ and a setting value of the exposure width in the radial direction based on the edge information; and after obtaining the peripheral photographic image, forming a coating F2 on at least the peripheral area on the surface Wa; and exposing the coating F2 in the peripheral area based on the exposure mapping. In the substrate processing method, the exposure mapping is set according to the edge information. Therefore, in the exposure mapping, the exposure width is set in accordance with the radial position of the outer edge of the film F1 located under the film F2, and according to such exposure mapping, the peripheral area can be exposed. Therefore, the exposure can be performed in accordance with the state of the outer edge of the lower film.

Using the example shown in FIG. 12( b ), consider the case where a negative photoresist material is used and the exposure width is set to a constant. For example, when the position of "Er1" shown in FIG. 12( b ) is set close to the center of the exposure range, in a certain range in the circumferential direction, the outer edge of the film F1 is not covered by the film F2, and the film F0 located further below the film F1 is exposed. In this case, the exposed portion of the film F0 that is not covered by the film F2 in the film F1 may affect the portion forming the concave-convex pattern. Therefore, for example, the position of "Er2" shown in FIG. 12( b ) is set close to the center of the exposure range when the exposure width is set to a constant. In addition, for each wafer W, the position of the outer edge of the film F1 is not detected, and the operation is usually performed at a certain exposure width. In this case, assuming the worst conditions, the exposure width is set to be closer to the inside than the outer edge of the film F1. In this way, when the exposure width is set at the position of "Er2", the area between the outer edge of the film F1 and the inner edge of the film F2 after exposure and development becomes larger. As a result, the area where the concave-convex pattern is formed in the film F1 in the state of being exposed due to the ring-shaped film F2 formed in the peripheral area. In the above substrate processing method, since the exposure width can be set along the shape of the outer edge of the film F1, the film F0 does not need to be exposed, and the situation that the area where the concave-convex pattern can be formed in the film F1 is reduced due to the film F2 can be avoided. Similarly, in the case of using a positive photoresist material, it is not necessary to remove the peripheral portion of the photoresist film (film F2) formed by using too much of the photoresist material. Therefore, the situation that the area where the concave-convex pattern can be formed in the film F2 is reduced due to the removal of the peripheral portion can be avoided.

[2] The substrate processing method described in [1] further includes a step of photographing a peripheral area of the surface Wa of the wafer W to obtain a peripheral photographic image. Even in this case, exposure can be performed in accordance with the state of the outer edge of the underlying film.

[3] A substrate processing method as described in [1] or [2] above, wherein, in exposure mapping, for each specific angle, the exposure width is set in such a manner that the position of one end of the exposure range close to the center of the wafer W is offset by a certain value from the outer edge position (the outer edge position of the film F1) indicated by the edge information. In this case, the exposure width can be set in a shape closer to the outer edge shape of the film F1. Furthermore, if a certain value is added or subtracted from the outer edge position of the film F1, the computational load when setting the exposure mapping can be reduced.

[4] A substrate processing method as described in any one of [1] to [3] above, wherein in the exposure mapping, an exposure width is set for each specific angle, and in the edge information, the outer edge position is obtained for each of the specific angles. In this case, since the outer edge position of the coating F1 is calculated using the minimum angle unit required for setting the exposure mapping, the computational load when calculating the outer edge position of the coating F1 can be reduced from the peripheral photography image.

[5] A substrate processing method as described in any one of [1] to [4] above, further comprising: a step of developing the film F2 in a manner that the film F2 remains in the peripheral area after exposure according to the exposure map; a step of photographing the peripheral area of the surface Wa of the wafer W after the development of the film F2 to obtain a determination photographic image; a step of generating cutting information indicating the relationship between the circumferential position Xθ and the inner edge position of the film F2 in the radial direction according to the determination photographic image; and a step of determining whether the exposure of the film F2 is normal according to the result of comparing the edge information and the exposure map with the cutting information. In this case, by checking the actual result after exposure, the reliability of the wafer W undergoing peripheral exposure can be improved.

[6] The substrate processing method described in [5] above, wherein the coating F2 is a photoresist film formed using a negative photoresist material. In this case, it is possible to evaluate whether the result of peripheral exposure of the photoresist film formed using a negative photoresist material is appropriate.

[7] A substrate processing method as described in any one of [1] to [4] above, further comprising: a step of developing in such a manner that a portion of the peripheral area of the film F2 is removed after exposure according to an exposure map; a step of photographing the peripheral area of the surface Wa of the wafer W after the development of the film F2 to obtain a determination photographic image; a step of generating cutting information indicating the relationship between the circumferential position Xθ and the outer edge position of the film F2 in the radial direction according to the determination photographic image; and a step of determining whether the exposure of the film F2 is normal according to the result of comparing the edge information and the exposure map with the cutting information. In this case, by checking the actual result after exposure, the reliability of the wafer W subjected to peripheral exposure can be improved.

[8] The substrate processing method described in [7] above, wherein the coating F2 is a photoresist film formed using a positive photoresist material. In this case, it is possible to evaluate whether the result of peripheral exposure of the photoresist film formed using a positive photoresist material is appropriate.

[9] A substrate processing method as described in any one of [1] to [8] above, wherein the step of exposing the coating F2 includes: irradiating the surface Wa with exposure light through a mask member 123 having an opening 123a; and moving the mask member 123 radially in a manner that changes the exposure width according to the exposure mapping. In this case, since it is not necessary to drive or adjust the member and the optical system for irradiating the exposure light according to the circumferential position during exposure, it is easy to change the exposure width.

[10] A substrate processing method as described in any one of [1] to [8] above, wherein the step of exposing the coating F2 comprises: irradiating the surface Wa with exposure light via a mask member 123 having an opening 123a and a baffle 125 capable of adjusting the opening of the opening 123a; and adjusting the opening by the baffle in a manner that changes the exposure width according to the exposure mapping. In this case, since it is not necessary to drive or adjust the member and the optical system for irradiating the exposure light according to the circumferential position during exposure, it is easy to change the exposure width.

[11] A substrate processing method as described in any one of [1] to [8] above, wherein the step of exposing the coating F2 includes: irradiating the surface Wa of the wafer W held on the holding table 111 with exposure light from an irradiation unit (light source 121 and optical system component 122) capable of irradiating exposure light; and moving the holding table 111 in a manner that changes the exposure width according to the exposure mapping. In this case, since it is not necessary to drive or adjust the components and optical system for irradiating exposure light according to the circumferential position during exposure, it is easy to change the exposure width.

[12] A substrate processing method as described in any one of [1] to [11] above, wherein, in the exposure mapping, the exposure width and the rotation speed of the wafer W are set for each specific angle, and the step of exposing the film F2 includes the step of irradiating the surface Wa with exposure light while changing the exposure width according to the exposure mapping while continuing the rotation of the wafer W, and the step of setting the exposure mapping includes: the step of repeatedly calculating the difference between the exposure width at the first angle and the exposure width at the second angle continuous with the first angle while changing the second angle one by one by the above specific angles; and the step of setting the rotation speed in the range to a value greater than the speed reference value when the condition that the difference is less than a specific reference is satisfied in a range including a continuous range of angles greater than the specific number. Consider performing peripheral exposure while continuing to rotate the wafer W and changing the exposure width in accordance with the circumferential position Xb (angle). In such peripheral exposure, when the degree of change in exposure width is continuously small, even if the rotation of the wafer W becomes faster, it is easy to use a device or component that changes the exposure width to follow the change in the set value of its exposure width. In the above method, when the difference between the continuous angles is less than the condition of a specific alignment, the rotation speed is set to a value greater than the reference value within the range only when a specific number is continuously satisfied. In this way, the processing time for performing peripheral exposure while changing the exposure width can be shortened. Therefore, it is effective in coordinating the exposure of the outer edge state of the underlying film and maintaining the production yield.

[13] The substrate processing method as described in [12] above, wherein in the exposure step, the illumination of the exposure light is further set for each specific angle, the step of exposing the film F2 includes the step of irradiating the surface Wa with the exposure light while adjusting the illumination according to the exposure map, and the step of setting the exposure map further includes the step of setting the illumination of the exposure light to a value greater than the illumination reference value in a range where the rotation speed is set to a value greater than the speed reference value. In this case, the exposure amount (e.g., doping amount) caused by the exposure light can be reduced between the range where the rotation speed is faster than the other range and the other range. Therefore, by increasing the rotation speed and shortening the processing time, it is possible to achieve uniform exposure state within the surface Wa of a wafer W.

[14] A substrate processing method as described in any one of [1] to [13] above, wherein in the exposure step, the exposure width and the rotation speed of the wafer W are set for each specific angle, and the step of exposing the film F2 includes the step of irradiating the surface Wa with exposure light while changing the exposure width according to the exposure map while continuing the rotation of the wafer W, and the step of setting the exposure map includes: while changing the second angle one by one at the specific angle, repeatedly calculating the difference between the exposure width at the first angle and the exposure width at the second angle continuous with the first angle, and setting the rotation speed at the angle satisfying the condition that the difference is greater than the specific calibration to a value greater than the speed reference value. Consider performing peripheral exposure while continuing to rotate the wafer W and changing the exposure width in accordance with the circumferential position Xb (angle). In such peripheral exposure, when the degree of change in exposure width is large, it is difficult to use a device or component that changes the exposure width to follow the change in the set value of the exposure width. In the above method, at an angle where the change in exposure width is large, the rotation speed is set to a value smaller than the speed reference value. Even in a place where the degree of change in exposure width is large, it is easy to use a device or component that changes the exposure width to follow the change in exposure width. Therefore, the device or component can be simplified.

[15] A substrate processing method as described in [14] above, wherein in the exposure step, the illumination of the exposure light is further set for each of the above-mentioned specific angles, the step of exposing the film F2 includes the step of irradiating the surface Wa with the exposure light while adjusting the illumination according to the exposure map, and the step of setting the exposure map further includes the step of setting the illumination of the exposure light at an angle where the rotation speed is set to a value smaller than the above-mentioned speed reference value to a value smaller than the illumination reference value. In this case, the difference in exposure amount (for example, doping amount) caused by the exposure light can be reduced between the angle (range) where the rotation speed is slower than the other range and the other range. Therefore, the uniformity of the exposure state within the surface Wa of a wafer W can be sought.

[16] A substrate processing method as described in any one of [1] to [15] above, wherein the step of exposing the film F2 includes: irradiating the surface Wa with exposure light through a mask member 123 having an opening, setting an exposure width and a position of the mask member 123 in the direction in which the exposure light is emitted for each specific angle in the exposure mapping, and the step of exposing the film F2 further includes a step of adjusting the position of the mask member 123 in the direction in which the exposure light is emitted according to the exposure mapping, and the step of setting the exposure mapping includes: setting the position of the mask member 123 in the direction in which the exposure light is emitted for each of the above-mentioned specific angles according to a warp state indicating a warp state in the peripheral region of the surface Wa. When the peripheral area of the wafer W has a warp, even if the exposure width setting value is the same, a difference will actually occur in the area irradiated with the exposure light. In the above method, since the position of the mask member 123 is also changed according to the warp information, even if the peripheral area of the wafer W includes a warp, the difference in the area irradiated with the exposure light due to the warp can be suppressed. Therefore, the exposure can be performed with better accuracy in accordance with the state of the outer edge of the lower film.

[17] A substrate processing device (wafer processing system 1) comprises: a film forming unit (film processing device U1 and heat treatment device U2) for forming a film on the surface Wa of a wafer W; a peripheral exposure device U4 for exposing the peripheral area of the surface Wa; an image information acquisition unit 201 for acquiring a peripheral photographic image of the peripheral area of the surface Wa of the wafer W in a state where a film F1 is formed on the surface Wa; an edge information generation unit 202 for generating a circumferential position X around the center of the wafer W based on the peripheral photographic image. θ, and the edge information of the relationship between the outer edge position of the film F1 in the radial direction of the wafer W; an exposure mapping setting unit 203, which sets an exposure mapping indicating the relationship between the circumferential position Xθ and the set value of the exposure width in the radial direction according to the edge information; a film formation control unit 205, which controls the film formation unit in a manner of forming a film F2 in at least the peripheral area of the formation surface Wa after obtaining the peripheral photographic image; and an exposure control unit 206, which controls the peripheral exposure device U4 in a manner of exposing the film F2 in the peripheral area according to the exposure mapping. In this substrate processing device, exposure can be performed in accordance with the state of the outer edge of the lower film, as in the substrate processing method described in [1] above.

[18] The substrate processing device described in [17] further includes an inspection device U3 capable of photographing the peripheral area of the surface Wa of the wafer W, and the image information acquisition unit 201 acquires the peripheral image from the inspection device U3. Even in this case, exposure can be performed in accordance with the state of the outer edge of the lower film.

[19] A substrate processing apparatus as described in [17] or [18] above, wherein the exposure mapping setting unit 203 sets the exposure mapping according to the edge information, and sets the exposure width for each specific angle in a manner that the position of one end of the exposure range close to the center of the wafer W is offset by a certain value from the outer edge position (the outer edge position of the film F1) indicated by the edge information. In the substrate processing apparatus, similar to the substrate processing method described in [3] above, the exposure width can be set in a shape closer to the outer edge shape of the film F1. Furthermore, if a certain value is added or subtracted from the outer edge position, the computational load when setting the exposure mapping can be reduced.

[20] A substrate processing apparatus as recited in any one of [17] to [19], wherein the exposure mapping setting unit 203 sets the exposure width for each specific angle in the exposure mapping, and the edge information generating unit 202 calculates the outer edge position for the specific angle. In the substrate processing apparatus, similar to the substrate processing method recited in [4] above, the outer edge position of the coating F1 is calculated using the minimum angle unit required for setting the exposure mapping, so that the computational load when calculating the outer edge position of the coating F1 can be reduced from the peripheral photography image.

1: Wafer processing system W: Wafer Wa: Surface U1: Film processing device U2: Heat treatment device U3: Inspection device U4: Peripheral exposure device 110: Rotation holding unit 111: Holding table 120: Exposure unit 123: Mask component 123a: Opening 125: Baffle 100: Control device 201: Image information acquisition unit 202: Edge information generation unit 203: Exposure mapping setting unit 205: Film formation control unit 206: Exposure control unit

[Figure 1] is a schematic top view of an example of a wafer processing system. [Figure 2] is a schematic front view of an example of a wafer processing system. [Figure 3] is a schematic diagram of an example of a liquid processing device. [Figure 4] is a schematic top view of an example of an inspection device. [Figure 5] is a schematic front view of an example of an inspection device. [Figure 6(a)] is a schematic diagram of an example of a peripheral exposure device. [Figure 6(b)] is a schematic side view of an example of a mask component. [Figure 7] is a block diagram of an example of a functional configuration of a control device. [Figure 8] is a block diagram of an example of a hardware configuration of a control device. [Figure 9] is a flow chart of an example of a substrate processing method. [Figure 10(a)], [Figure 10(b)], [Figure 10(c)], [Figure 10(d)], [Figure 10(e)], and [Figure 10(f)] are schematic diagrams illustrating the substrate processing method. [Figure 11(a)] is a diagram showing an example of a peripheral photographic image. [Figure 11(b)] is a graph showing edge information. [Figure 12(a)] is a graph showing an example of an exposure map by making it visible. [Figure 12(b)] is a diagram schematically showing an example of the state of a film after exposure and development. [Figure 13] is a graph showing an example of the relationship between edge information and exposure mapping. [Figure 14(a)] is a graph showing an example of the measurement result of the exposure width after exposure. [Figure 14(b)] is a graph showing an example of differential information obtained in the inspection process. [Figure 15(a)], [Figure 15(b)], [Figure 15(c)], [Figure 15(d)], [Figure 15(e)], and [Figure 15(f)] are schematic diagrams showing examples of substrate processing methods. [Figure 16(a)], [Figure 16(b)], [Figure 16(c)], and [Figure 16(d)] are schematic diagrams showing examples of substrate processing methods. [Figure 17(a)] is a schematic diagram showing an example of the influence caused by warp. [Figure 17(b)] is a schematic diagram showing an example of a peripheral exposure device.

Ees:Exposure width

Eo: Outer Edge

E1: Outer edge position

Eer: Inner edge position

F1: Lamination

F2: Lamination

Xθ: Circumferential position

Claims (20)

A substrate processing method comprises: A step of generating edge information representing the relationship between the circumferential position around the center of the substrate and the outer edge position of the first coating in the radial direction of the substrate based on a photographic image obtained by photographing a peripheral area in the surface of the substrate on which a first coating is formed; A step of setting an exposure map representing the relationship between the circumferential position and the set value of the exposure width in the radial direction based on the edge information; A step of forming a second coating in at least the peripheral area in the surface after obtaining the photographic image; and A step of exposing the second coating in the peripheral area based on the exposure map. The substrate processing method as set forth in claim 1 further comprises the step of photographing the peripheral area of the surface of the substrate to obtain the photographic image. A substrate processing method as set forth in claim 1, wherein In the exposure mapping, for each specific angle, the exposure width is set in such a manner that the position of one end of the exposure range close to the center of the substrate is offset by a certain value from the outer edge position indicated by the edge information. A substrate processing method as set forth in any one of claims 1 to 3, wherein in the exposure mapping, the exposure width is set for each specific angle, in the edge information, the outer edge position is obtained for each specific angle. A substrate processing method as set forth in any one of claims 1 to 3, wherein further comprises: a step of developing the substrate in such a manner that the second coating remains in the peripheral region after exposure according to the exposure mapping; a step of obtaining a second photographic image by photographing the peripheral region on the surface of the substrate after the development of the second coating; a step of generating cutting information indicating the relationship between the circumferential position and the inner edge position of the second coating in the radial direction according to the second photographic image; and a step of determining whether the exposure of the second coating is normal according to the result of comparing the edge information and any one of the exposure mapping and the cutting information. The substrate processing method as set forth in claim 5, wherein the second coating is a photoresist film formed using a negative photoresist material. A substrate processing method as set forth in any one of claims 1 to 3, wherein further comprises: a step of developing in such a manner that a portion of the peripheral area located in the second coating is removed after exposure according to the exposure mapping; a step of photographing the peripheral area on the surface of the substrate after the development of the second coating to obtain a second photographic image; a step of generating cutting information indicating the relationship between the circumferential position and the outer edge position of the second coating in the radial direction according to the second photographic image; and a step of determining whether the exposure of the second coating is normal according to the result of comparing the edge information and any one of the exposure mappings and the cutting information. The substrate processing method as set forth in claim 7, wherein the second coating is a photoresist film formed using a positive photoresist material. A substrate processing method as set forth in any one of claims 1 to 3, wherein the step of exposing the second coating comprises: a step of irradiating the surface with exposure light through a mask member having an opening; and a step of moving the mask member in the radial direction by changing the exposure width according to the exposure mapping. A substrate processing method as set forth in any one of claims 1 to 3, wherein the step of exposing the second coating comprises: irradiating the surface with exposure light through a mask member having an opening and a baffle capable of adjusting the opening degree of the opening; and adjusting the opening degree by the baffle in a manner of changing the exposure width according to the exposure mapping. A substrate processing method as set forth in any one of claims 1 to 3, wherein the step of exposing the second coating comprises: irradiating the surface of the substrate held by a holding portion with the exposure light from an irradiation portion capable of irradiating the exposure light; and moving the holding portion in a manner that changes the exposure width according to the exposure mapping. A substrate processing method as set forth in any one of claims 1 to 3, wherein in the exposure mapping, the exposure width and the rotation speed of the substrate are set for each specific angle, the step of exposing the second coating includes the step of irradiating the surface with exposure light while changing the exposure width according to the exposure mapping while continuing the rotation of the substrate, the step of setting the exposure mapping includes: while changing the second angle one by one at the specific angles, the step of repeatedly calculating the difference between the exposure width at the first angle and the exposure width at the second angle continuous with the first angle; and When the condition that the difference is less than a specific calibration is satisfied in a range including a continuous angle of a specific number or more, the step of setting the rotation speed in the range to a value greater than the speed reference value. A substrate processing method as set forth in claim 12, wherein in the exposure step, the illumination of the exposure light is further set for each specific angle, the step of exposing the second coating includes the step of irradiating the surface with the exposure light while adjusting the illumination according to the exposure mapping, the step of setting the exposure mapping further includes the step of setting the illumination of the exposure light to a value greater than the illumination reference value in a range where the rotation speed is set to a value greater than the speed reference value. A substrate processing method as set forth in any one of claims 1 to 3, wherein in the exposure mapping, the exposure width and the rotation speed of the substrate are set for each specific angle, the step of exposing the second coating includes the step of irradiating the surface with exposure light while changing the exposure width according to the exposure mapping while continuing the rotation of the substrate, the step of setting the exposure mapping includes: while changing the second angle one by one at the specific angle, repeatedly calculating the difference between the exposure width at the first angle and the exposure width at the second angle continuous with the first angle; and and setting the rotation speed at the angle satisfying the condition that the difference is greater than the specific alignment to a value greater than the speed reference value. A substrate processing method as set forth in claim 14, wherein in the exposure mapping, the illumination of the exposure light is further set for each specific angle, the step of exposing the second coating includes the step of irradiating the surface with the exposure light while adjusting the illumination according to the exposure mapping, the step of setting the exposure mapping further includes the step of setting the illumination of the exposure light at an angle where the rotation speed is set to a value smaller than the speed reference value to a value smaller than the illumination reference value. A substrate processing method as set forth in any one of claims 1 to 3, wherein the step of exposing the second coating includes the step of irradiating the surface with exposure light through a mask member having an opening, in the exposure mapping, even if the exposure width and the position of the mask member in the direction in which the exposure light is emitted are set for each specific angle, the step of exposing the second coating further includes the step of adjusting the position of the mask member in the direction in which the exposure light is emitted according to the exposure mapping, the step of setting the exposure mapping includes: according to the warp state representing the warp state of the peripheral area of the surface, the step of setting the position of the mask member in the direction in which the exposure light is emitted for each specific angle. A substrate processing device comprises: a coating forming unit for forming a coating on the surface of a substrate; a peripheral exposure unit for exposing a peripheral area on the surface; an image information acquisition unit for acquiring a photographic image of the peripheral area on the surface of the substrate in a state where a first coating is formed on the surface; an edge information generation unit for generating edge information representing the relationship between a circumferential position around the center of the substrate and an outer edge position of the first coating in the radial direction of the substrate based on the peripheral photographic image; an exposure mapping setting unit for setting an exposure mapping representing the relationship between the circumferential position and a setting value of the exposure width in the radial direction based on the edge information; A film forming control unit controls the film forming unit in a manner that a second film is formed on at least the peripheral region of the surface after the photographic image is obtained; and an exposure control unit controls the peripheral exposure unit in a manner that the second film is exposed on the peripheral region according to the exposure mapping. The substrate processing device as set forth in claim 17, wherein it further comprises an inspection unit capable of photographing the peripheral area of the surface of the substrate, and the image information acquisition unit acquires the photographic image from the inspection unit. The substrate processing device as set forth in claim 17, wherein the exposure mapping setting unit sets the exposure mapping according to the edge information, and for each specific angle, sets the exposure width in a manner such that the position of one end of the exposure range close to the center of the substrate is offset by a certain value from the outer edge position represented by the edge information. A substrate processing device as set forth in any one of claim items 17 to 19, wherein the exposure mapping setting unit sets the exposure width for each specific angle in the exposure mapping, and the edge information generating unit calculates the outer edge position for each specific angle.

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