JP7602924B2 - SUBSTRATE PROCESSING APPARATUS, SUBSTRATE PROCESSING SYSTEM, SUBSTRATE PROCESSING METHOD, AND COMPUTER STORAGE MEDIUM - Google Patents

Description

The present disclosure relates to a substrate processing apparatus, a substrate processing system, a substrate processing method, and a computer storage medium.

Patent document 1 discloses a substrate processing apparatus including a rotating means for rotating a substrate around a rotation axis perpendicular to its main surface, a light source for outputting laser light, a light branching means for branching the laser light to generate a first light beam and a second light beam and capable of changing the power ratio between the first light beam and the second light beam, a first light path adjustment means for changing the traveling direction of the first light beam to cause the first light beam to be incident on the peripheral portion of the substrate along a first incident direction having a component in a direction from the first main surface of the substrate to a second main surface opposite the first main surface, and a second light path adjustment means for changing the traveling direction of the second light beam to cause the second light beam to be incident on the peripheral portion of the substrate along a second incident direction having a component in a direction from the second main surface to the first main surface.

JP 2016-115893 A

The technology disclosed herein suppresses the occurrence of humps and erosion in the coating film during EBR (edge bead removal) processing of the substrate.

One aspect of the present disclosure is a substrate processing apparatus comprising: a substrate holding unit that holds and rotates a substrate having a coating film for pattern formation formed thereon; a processing liquid discharge unit that discharges a processing liquid for forming a protective film on the substrate held by the substrate holding unit; a laser irradiation unit that irradiates a peripheral portion of the substrate having the protective film with a laser; a solvent discharge unit that discharges a solvent; a removal liquid discharge unit that discharges a removal liquid onto the protective film for removing the protective film; and a control unit that controls operation of the laser irradiation unit and the solvent discharge unit , wherein the control unit is configured to control the irradiation of the laser to a predetermined target removal area of the coating film and the discharge of the solvent onto the coating film remaining in an area radially outward of the substrate from the laser irradiation area .

This disclosure makes it possible to suppress the occurrence of humps and erosion of the coating film during EBR (edge bead removal) processing of the substrate.

1 is a plan view diagrammatically illustrating an outline of a configuration of a substrate processing system according to a first embodiment; 2 is a front view showing a schematic configuration of the substrate processing system of FIG. 1; FIG. 2 is a rear view diagrammatically illustrating an outline of the configuration of the substrate processing system of FIG. 1. 1 is a side cross-sectional view that typically illustrates an outline of the configuration of a substrate processing apparatus according to a first embodiment. 4 is a plan view for explaining a laser irradiation unit, a processing liquid discharge unit, and a removal liquid discharge unit. FIG. FIG. 2 is a diagram showing a substrate processing flow according to the first embodiment; 7 is an explanatory diagram showing the operations of a laser irradiation unit, a processing liquid discharge unit, and a removal liquid discharge unit when performing substrate processing according to the flow of FIG. 6. FIG. 4 is an enlarged view of the peripheral portion of the substrate for explaining a laser irradiation method. FIG. 11 is a side cross-sectional view that illustrates a schematic configuration of a substrate processing apparatus according to a second embodiment. FIG. 11 is a front view illustrating a schematic configuration of a substrate processing system according to a second embodiment. FIG. 11 is a diagram showing a substrate processing flow according to a second embodiment. FIG. 11 is a diagram showing another substrate processing flow according to the second embodiment. FIG. 11 is a side cross-sectional view that illustrates a schematic configuration of a substrate processing apparatus according to a third embodiment. FIG. 13 is a diagram showing a substrate processing flow according to a third embodiment. 15A to 15C are explanatory views showing the state of a coating film on a substrate when the substrate is processed according to the flow of FIG. 14 .

In the manufacturing process of semiconductor devices, etc., there is a process of forming a resist film as a coating film for pattern formation on the surface of a substrate such as a semiconductor wafer (hereinafter sometimes referred to as "wafer"). In this process, a solvent such as thinner is discharged onto the peripheral edge of the wafer on which the resist film has been formed, and unnecessary resist film on the peripheral edge of the wafer is removed, a process known as edge bead removal (hereinafter sometimes referred to as "EBR process").

When this EBR process is performed using a solvent such as thinner, while the solvent removes unnecessary resist film, it can also cause protrusions (hereafter referred to as "humps") or erosion of the resist film necessary for pattern formation, which can cause the peripheral shape of the resist film used for pattern formation to collapse. Such collapse of the resist film shape can cause defects such as pattern abnormalities in subsequent processes.

Therefore, the technology disclosed herein suppresses the occurrence of humps and erosion of the coating film during EBR processing of the substrate.

The substrate processing apparatus and substrate processing method according to the embodiment will be described below with reference to the drawings. Note that in this specification and the drawings, elements having substantially the same functional configuration are designated by the same reference numerals, and duplicated explanations will be omitted.

First Embodiment
Before describing the substrate processing apparatus according to this embodiment, a substrate processing system including the substrate processing apparatus will be described.

(Substrate Processing System)
Fig. 1 is a plan view showing a schematic configuration of a substrate processing system according to a first embodiment, while Fig. 2 and Fig. 3 are a front view and a rear view showing a schematic internal configuration of the substrate processing system 1.

As shown in FIG. 1, the substrate processing system 1 has a cassette station 10 where cassettes C containing multiple wafers W as substrates are loaded and unloaded, and a processing station 11 equipped with multiple processing devices that perform predetermined processing on the wafers W. The substrate processing system 1 has a configuration in which the cassette station 10, the processing station 11, and an interface station 13 that transfers the wafers W between the processing station 11 and an exposure device 12 adjacent to the processing station 11 are integrally connected.

The cassette station 10 is provided with a cassette placement table 20. The cassette placement table 20 is provided with a plurality of cassette placement plates 21 on which the cassettes C are placed when the cassettes C are loaded or unloaded from the outside of the substrate processing system 1.

The cassette station 10 is provided with a wafer transport device 23 that is movable on a transport path 22 that extends in the X direction in FIG. 1. The wafer transport device 23 is also movable in the vertical direction and around the vertical axis (θ direction), and can transport wafers W between the cassettes C on each cassette mounting plate 21 and a transfer device in the third block G3 of the processing station 11, which will be described later.

The processing station 11 is provided with multiple, for example, four, blocks G1, G2, G3, and G4 equipped with various devices. For example, a first block G1 is provided on the front side of the processing station 11 (negative side in the X direction in FIG. 1), and a second block G2 is provided on the rear side of the processing station 11 (positive side in the X direction in FIG. 1). A third block G3 is provided on the cassette station 10 side of the processing station 11 (negative side in the Y direction in FIG. 1), and a fourth block G4 is provided on the interface station 13 side of the processing station 11 (positive side in the Y direction in FIG. 1).

As shown in FIG. 2, the first block G1 is provided with a plurality of liquid processing devices, such as a developing device 30 and a resist coating device 31 as a coating processing device. The developing device 30 develops the wafer W. The resist coating device 31 supplies resist liquid to the wafer W to form a resist film as a coating film. The number and arrangement of the developing device 30 and resist coating device 31 can be selected arbitrarily.

In the developing treatment device 30 and the resist coating device 31, for example, spin coating is performed on the wafer W using a predetermined processing liquid or coating liquid. In spin coating, for example, the processing liquid or coating liquid is ejected from a nozzle onto the wafer W, and the wafer W is rotated to spread the processing liquid or coating liquid over the surface of the wafer W.

As shown in FIG. 3, in the second block G2, a heat treatment device 40 and an edge exposure device 41 are arranged vertically and horizontally. The heat treatment device 40 performs heat treatment such as heating and cooling the wafer W. For example, the heat treatment device 40 performs a baking process on the wafer W on which a resist film is formed. The edge exposure device 41 exposes the outer periphery of the wafer W. The number and arrangement of the heat treatment devices 40 and edge exposure devices 41 can be selected arbitrarily.

For example, in the third block G3, multiple transfer devices 50, 51, 52, 53, 54, 55, and 56 are provided in order from the bottom. In addition, in the fourth block G4, multiple transfer devices 60, 61, and 62 are provided in order from the bottom.

As shown in Figures 1 and 3, a wafer transport area D is formed in the area surrounded by the first block G1 to the fourth block G4. A wafer transport device 70 is disposed in the wafer transport area D.

Each wafer transport device 70 has a transport arm 70a that can move, for example, in the Y direction, X direction, θ direction, and up and down. Multiple wafer transport devices 70 are arranged one above the other, and each wafer transport device 70 moves within the wafer transport area D and can transport the wafer W to a specified device at approximately the same height in each of blocks G1 to G4, for example.

In addition, a shuttle transfer device 80 is provided in the wafer transfer area D to transfer the wafer W linearly between the third block G3 and the fourth block G4.

The shuttle transfer device 80 is movable linearly, for example, in the Y direction in FIG. 3. The shuttle transfer device 80 moves in the Y direction while supporting the wafer W, and can transfer the wafer W between the transfer device 52 in the third block G3 and the transfer device 62 in the fourth block G4.

As shown in FIG. 1, a wafer transfer device 90 is provided next to the third block G3 on the positive side in the X direction. The wafer transfer device 90 has a transfer arm 90a that can move, for example, in the X direction, the θ direction, and the vertical direction. The wafer transfer device 90 can move up and down while supporting a wafer W, and transfer the wafer W to each transfer device in the third block G3.

The interface station 13 is provided with a wafer transfer device 100 and a transfer device 101. The wafer transfer device 100 has a transfer arm 100a that is movable, for example, in the Y direction, the θ direction, and the up and down directions. The wafer transfer device 100 can support a wafer W on the transfer arm 100a, for example, and transfer the wafer W between each transfer device in the fourth block G4, the transfer device 101, and the exposure device 12.

The substrate processing system 1 described above is provided with a control unit 200. The control unit 200 is configured, for example, by a computer equipped with a CPU, memory, etc., and has a program storage unit (not shown). The program storage unit stores programs that control various processes in the substrate processing system 1. The above programs may be recorded on a computer-readable storage medium H and installed from the storage medium H to the control unit 200. A part or all of the programs may be realized by dedicated hardware (circuit board). It does not matter whether the storage medium H is a temporary storage medium or a non-temporary storage medium.

Next, a resist coating apparatus 31 as a substrate processing apparatus according to this embodiment will be described. FIG. 4 is a side cross-sectional view that shows a schematic outline of the configuration of the resist coating apparatus 31 according to this embodiment.

The resist coating device 31 has a processing vessel 301 whose interior can be sealed. A loading/unloading port (not shown) for the wafer W is formed on the side of the processing vessel 301.

A spin chuck 302 is provided in the processing vessel 301 as a substrate holder for holding the wafer W. The spin chuck 302 can be rotated at a predetermined speed by a chuck driver 303 having an actuator such as a motor, and can rotate the wafer W held by the spin chuck 302. The chuck driver 303 is also provided with a lifting and lowering mechanism such as a cylinder, and the spin chuck 302 can be raised and lowered freely.

In addition, a cup 304 is provided in the processing vessel 301, which is disposed outside the spin chuck 302 and surrounds the wafer W held by the spin chuck 302. The cup 304 includes an outer cup 305 that receives and collects liquid that splashes or falls from the wafer W, and an inner cup 306 that is located on the inner periphery of the outer cup 305. An opening 307 is formed on the upper surface of the outer cup 305 through which the wafer W passes before and after the wafer W is transferred to the spin chuck 302. In addition, a nozzle unit 308 for ejecting resist liquid onto the wafer W is provided in the processing vessel 301 so as to be movable in the vertical and horizontal directions.

In addition, the resist coating device 31 in this embodiment is equipped with a laser irradiation mechanism 310 that irradiates a laser onto the peripheral portion of the wafer W, and a processing liquid ejection mechanism 320 that ejects a processing liquid for forming a protective film onto the wafer W on which a resist film has been formed.

The laser irradiation mechanism 310 includes a laser light source 311, an attenuator 312, a mask 313, and a laser irradiation unit 314. A mirror 315 is provided inside the laser irradiation unit 314. The laser light indicated by the dashed arrow in FIG. 4 outputted in the horizontal direction from the laser light source 311 passes through the attenuator 312 and the mask 313, travels vertically downward due to reflection from the mirror 315, and is irradiated onto the wafer W via a lens (not shown) of the laser irradiation unit 314. In this embodiment, the laser irradiation unit 314 is configured to be freely movable horizontally along the reciprocating arrow A by an arm equipped with a drive mechanism (not shown).

The structure and installation position of the laser irradiation mechanism 310 are not particularly limited as long as the structure can irradiate the laser toward the resist film on the wafer periphery. For example, in this embodiment, the laser irradiation unit 314 is configured to be freely movable horizontally along the reciprocating arrow A, but the spin chuck 302 may be configured to be freely movable horizontally along the reciprocating arrow A. The laser irradiation position on the wafer W may be changed by adjusting the angle of the mirror 315, rather than by horizontally moving the laser irradiation unit 314 or the spin chuck 302. The type, oscillation form, and wavelength of the laser light are not particularly limited as long as the resist film can be removed, but it is preferable that the laser be a solid-state laser with a wavelength of 240 nm or more. Furthermore, it is preferable that the laser be a pulsed laser.

The treatment liquid ejection mechanism 320 includes a treatment liquid supply source 321 that supplies the treatment liquid for forming the protective film, a treatment liquid supply pipe 322 that serves as a flow path for the treatment liquid, and a treatment liquid nozzle 323 as a treatment liquid ejection section. In this embodiment, the treatment liquid nozzle 323 is composed of a nozzle body 323a and a nozzle support section 323b that supports the nozzle body 323a. The treatment liquid nozzle 323 is configured to be freely movable horizontally along the reciprocating arrow B by an arm equipped with a drive mechanism (not shown). The structure and installation position of the treatment liquid ejection mechanism 320 are not particularly limited, and it is sufficient that the structure is capable of ejecting the treatment liquid onto the upper surface of the resist film.

The type of treatment liquid is not particularly limited, and it is sufficient that it is soluble in the protective film removal liquid described below and does not adversely affect the quality of the substrate or the coating film. For example, if the coating film formed on the substrate is a resist film, the protective film will dissolve together with the resist film when the protective film is removed using an organic solvent such as thinner as a protective film removal liquid. For this reason, when the coating film is a resist film, it is preferable that the protective film is a water-soluble film. If the protective film is a water-soluble film, pure water can be used as the protective film removal liquid, and only the protective film can be removed without dissolving the resist film. As a treatment liquid for forming such a water-soluble protective film, for example, a water-soluble resist such as PVA (polyvinyl alcohol) is used.

5 is a schematic diagram of the laser irradiation unit 314 and the processing liquid nozzle 323 seen from above. As shown in FIG. 5, the resist coating device 31 in this embodiment is provided with a removing liquid ejection mechanism 330 that ejects a removing liquid for removing a protective film and has a structure similar to that of the processing liquid ejection mechanism 320. The removing liquid ejection mechanism 330 includes a removing liquid supply source 331 that supplies the removing liquid, a removing liquid supply pipe 332 that serves as a flow path for the removing liquid, and a removing liquid nozzle 333 as a removing liquid ejection unit. The removing liquid nozzle 333 in this embodiment is composed of a nozzle body 333a and a nozzle support part 333b that supports the nozzle body 333a. The removing liquid nozzle 333 is configured to be freely movable in the horizontal direction along the reciprocating arrow C by an arm equipped with a driving mechanism (not shown). The structure and installation position of the removing liquid ejection mechanism 330 are not particularly limited, and it is sufficient if the structure is capable of ejecting the removing liquid onto the protective film formed on the upper surface of the resist film.

There are no particular limitations on the type of removal liquid, as long as it is capable of dissolving the protective film and does not adversely affect the quality of the substrate or the coating film. For example, pure water can be used as the removal liquid for a water-soluble protective film formed on the top surface of a resist film.

The resist coating apparatus 31 in this embodiment is configured as described above. Next, a method for processing a wafer W using this resist coating apparatus 31 will be described. Processing of a wafer W in this embodiment is performed according to the flow shown in FIG. 6.

First, resist liquid is ejected onto the center of the wafer W held on the spin chuck 302, and the spin chuck 302 is rotated to form a resist film on the wafer W.

Next, as shown in FIG. 7(a), the processing liquid nozzle 323 for forming the protective film is moved to the peripheral portion of the wafer W on which the resist film R is formed. At this time, the processing liquid nozzle 323 is moved so that the discharge position of the processing liquid is located at least in a region radially inward of the wafer W from the laser irradiation region described below. Next, the processing liquid is discharged while rotating the spin chuck 302, and the discharged processing liquid is dried by the rotation of the spin chuck 302, and a protective film P is formed on the upper surface of the resist film R as shown in FIG. 7(b). Note that in this embodiment, the protective film P is formed only on the peripheral portion of the wafer W on which the resist film R is formed, but the processing liquid may be discharged to the center of the wafer W, and the protective film P may be formed on the entire wafer W by rotating the spin chuck 302.

Next, as shown in FIG. 7(c), the processing liquid nozzle 323 is retracted to the outside of the wafer W, and the laser irradiation unit 314 is moved to the peripheral edge of the wafer W. Next, the laser is irradiated while rotating the spin chuck 302.

When the laser is a pulsed laser, the laser is irradiated as shown in FIG. 8. FIG. 8 is an enlarged plan view showing the state of the peripheral portion of the wafer W during laser irradiation. The left side of FIG. 8 is the central portion of the wafer W, and the right side of FIG. 8 is the end portion of the wafer W. In the example shown in FIG. 8, the laser irradiation is performed so that the irradiation areas per time overlap each other in the circumferential direction of the wafer W (the direction of the arrow in the figure). In detail, the first laser irradiation is performed on the area L ₁ , and then the second laser irradiation is performed so as to overlap the area L _1. Then, the third laser irradiation is performed so as to overlap the area L ₂ irradiated with the laser the second time. In this way, the resist film is removed along the circumferential direction of the wafer W by irradiating the areas L ₁ to L ₆ in order so that they overlap each other. At this time, the position of the laser irradiation unit 314 (FIG. 7(b)) is fixed. After the removal of the resist film from one circumference of the wafer W is completed, the laser irradiation unit 314 is moved from the region where the laser irradiation has been completed to the center side of the wafer W, and the laser irradiation is performed on the unirradiated region. The irradiation pitch of the pulsed laser and the rotation speed of the spin chuck 302 are appropriately set so that the above-mentioned laser irradiation is possible.

The laser irradiated toward the wafer W penetrates the protective film P and reaches the resist film R. As a result, heat is generated at the interface between the wafer W and the resist film R, and the resist film R expands at the heat generation portion, causing the resist film R at the laser irradiation portion to peel off from the wafer W together with the protective film P formed on the upper surface of the resist film R. As a result, unnecessary resist film R at the peripheral portion of the wafer W is removed. As shown in FIG. 7(a) and FIG. 7(b), in this embodiment, the discharge of the processing liquid and the laser irradiation are performed at different times. However, if the processing liquid discharged onto the wafer W is dried before reaching the laser irradiation position and functions as the protective film P, the processing liquid nozzle 323 and the laser irradiation unit 314 may each be moved to the peripheral portion of the wafer W, and the discharge of the processing liquid and the laser irradiation may be performed in the same process.

Next, as shown in FIG. 7(d), the laser irradiation unit 314 is withdrawn to the outside of the wafer W, and the removal liquid nozzle 333 is moved to the formation area of the protective film P remaining on the wafer W irradiated with the laser. At this time, the removal liquid nozzle 333 is moved so that the ejection position of the removal liquid is located in an area radially inward of the formation area of the protective film P. Next, the removal liquid is ejected while rotating the spin chuck 302, thereby removing the protective film P. Then, by removing the protective film P, unnecessary resist film R is removed from the surface of the wafer W, and only the resist film R necessary for pattern formation remains, completing the EBR process. After that, the wafer W is transported to, for example, a heat treatment device 40, and baked.

As described above, in the method for processing the wafer W in this embodiment, the EBR process is performed using a laser, so no solvent such as thinner is used during the EBR process. This makes it possible to prevent the occurrence of humps and erosion of the resist film, which are necessary for pattern formation.

When EBR processing is performed using a laser, there is a concern that the dried resist may scatter as debris to locations other than the peripheral portion of the wafer W due to laser irradiation. However, in the processing method for the wafer W in this embodiment, a protective film P is formed on the upper surface of the resist film R before laser irradiation, so that debris generated by laser irradiation scatters on the upper surface of the protective film P. Since this protective film P is removed by a removal liquid, the debris scattered on the upper surface of the protective film P is also removed together with the protective film P. In other words, according to the processing method of forming the protective film P before laser irradiation as in this embodiment, it is possible to suppress the occurrence of humps and erosion of the resist film R, and also to take measures against debris during laser irradiation. As a measure against debris, there is also a method of performing laser irradiation while blowing a gas such as nitrogen gas from the radial inside to the outside of the wafer W.

Second Embodiment
The resist coating apparatus 31 in the first embodiment has a laser irradiation function and thereby has a function of performing EBR processing of the wafer W, but this laser irradiation function may be realized by a dedicated module. Fig. 9 is a side cross-sectional view showing a schematic outline of the configuration of a laser irradiation apparatus 32 as a substrate processing apparatus according to the second embodiment.

The laser irradiation device 32 in this embodiment shown in FIG. 9 does not have a nozzle unit 308 compared to the resist coating device 31 shown in FIG. 4, but the other structures are substantially the same as those of the resist coating device 31. That is, the laser irradiation device 32 has a process container 401 whose interior can be sealed, and a spin chuck 402 is provided in the process container 401 as a substrate holding unit that holds the wafer W. The spin chuck 402 can be rotated at a predetermined speed by a chuck drive unit 403, and a cup 404 is provided in the process container 401, located outside the spin chuck 402, to surround the wafer W held by the spin chuck 402.

The laser irradiation device 32 further includes a laser irradiation mechanism 410 that irradiates the peripheral portion of the wafer W with a laser. The laser irradiation mechanism 410 includes a laser light source 411, an attenuator 412, a mask 413, and a laser irradiation section 414. A mirror 415 is provided inside the laser irradiation section 414.

The laser irradiation device 32 also includes a processing liquid discharge mechanism 420 that discharges a processing liquid for forming a protective film onto the wafer W on which a resist film has been formed. The processing liquid discharge mechanism 420 includes a processing liquid supply source 421, a processing liquid supply pipe 422, and a processing liquid nozzle 423 as a processing liquid discharge part. The processing liquid nozzle 423 in this embodiment is composed of a nozzle body 423a and a nozzle support part 423b that supports the nozzle body 423a. Although not shown, the laser irradiation device 32 also includes a removal liquid discharge mechanism similar to the removal liquid discharge mechanism 330 of the resist coating device 31 shown in FIG. 4. The structure of the laser irradiation device 32 is not particularly limited, and may be any structure that can irradiate the peripheral part of the wafer W transported to the laser irradiation device 32 with a laser.

As shown in FIG. 10, the laser irradiation device 32 is arranged, for example, in the first block G1 of the substrate processing system 1. Therefore, in the substrate processing system 1 in this embodiment, the resist coating device 31 as a coating processing device, the heat treatment device 40 (FIG. 3) that performs heat treatment of the wafer W, and the laser irradiation device 32 as a substrate processing device that performs EBR treatment are arranged as independent processing devices. Note that when the laser irradiation function is realized by a dedicated module as in this embodiment, a known configuration can be applied to the configuration of the resist coating device. Also, a known configuration can be applied to the configuration of the heat treatment device 40.

According to such a substrate processing system 1, the wafer W is transported through the resist coating device 31, the heat treatment device 40, and the laser irradiation device 32 in that order, and predetermined processing is performed in each device, thereby performing processing according to the flow shown in FIG. 11, for example. Note that the resist film formation, protective film formation, laser irradiation, and protective film removal shown in FIG. 11 may be performed in the same manner as described in the first embodiment. Also, the bake process shown in FIG. 11 may be performed by a known method.

When a bake process is performed after the formation of a resist film, as in the processing of a wafer W shown in FIG. 11, the resist film solidifies during the bake process, and therefore the resist film after the bake process cannot be removed by an EBR process using a solvent such as thinner. On the other hand, when processing a wafer W using the laser irradiation device 32 according to this embodiment, the solidified resist film after the bake process can be removed. In other words, the EBR process with the flow shown in FIG. 11 is a process that can be realized by the substrate processing system 1 according to this embodiment.

In addition, according to the substrate processing system 1 equipped with the laser irradiation device 32, for example, as shown in the flow chart of FIG. 12, the resist coating process in the resist coating device 31 and the bake process in the heat treatment device 40 can be alternately performed two or more times (three times in the example of FIG. 12), and then the EBR process can be performed. As described above, since it is difficult to remove the resist film after the bake process with a solvent, when performing the EBR process using a solvent in forming a multi-layer resist film on the wafer W, it is necessary to perform the EBR process between the formation of the resist film and the bake process. For example, when performing the EBR process using only a solvent in forming a three-layer resist film as shown in FIG. 11, the EBR process is performed each time the resist film of each layer is formed, so a total of three EBR processes are required. In contrast, according to the substrate processing system 1 according to the present embodiment, the unnecessary resist film removal process is completed by performing the EBR process once after forming the three-layer resist film, so that the throughput can be significantly improved. Furthermore, since unnecessary resist films can be removed at the same time after forming the multi-layer resist film, the peripheral edges of each resist film are aligned, improving the overlay accuracy of each resist film.

Third Embodiment
In the above embodiment, a protective film is formed as a measure against debris during laser irradiation, but the formation of a protective film is not essential from the viewpoint of suppressing humps and erosion of the coating film caused by contact with a solvent.

Another aspect of the present disclosure, in which the formation of a protective film is not essential, is a substrate processing apparatus that includes a substrate holding unit that holds and rotates a substrate on which a coating film for pattern formation has been formed, a laser irradiation unit that irradiates a peripheral portion of the substrate held by the substrate holding unit with a laser, a solvent discharge unit that discharges a solvent, and a control unit that controls the operation of the laser irradiation unit and the solvent discharge unit, and the control unit is configured to control the irradiation of the laser to a predetermined target removal area of the coating film and the discharge of the solvent to the coating film remaining in an area radially outside the irradiation area of the laser on the substrate.

In the third embodiment, the above-mentioned embodiment will be described. FIG. 13 is a side cross-sectional view that shows a schematic outline of the configuration of a resist coating device 31 as a substrate processing device according to this embodiment.

The resist coating apparatus 31 in this embodiment does not include the treatment liquid discharge mechanism 320 (FIG. 4) and the removal liquid discharge mechanism 330 (FIG. 5) of the resist coating apparatus 31 in the first embodiment, but includes a solvent discharge mechanism 340 (FIG. 13) that discharges a solvent. The solvent discharge mechanism 340 includes a solvent supply source 341 that supplies a solvent, a solvent supply pipe 342 that serves as a flow path for the solvent, and a solvent discharge nozzle 343 as a solvent discharge section. The solvent discharge nozzle 343 in this embodiment is composed of a nozzle body 343a and a nozzle support section 343b that supports the nozzle body 343a. The solvent discharge nozzle 343 is configured to be freely movable in the horizontal direction along the reciprocating arrow B by an arm equipped with a drive mechanism (not shown). The structure of the solvent discharge mechanism 340 is not particularly limited, and may be any structure that can discharge a solvent onto a resist film. For example, thinner is used as the solvent.

The resist coating apparatus 31 in this embodiment is configured as described above. Next, a method for processing a wafer W using this resist coating apparatus 31 will be described. Processing of a wafer W in this embodiment is performed according to the flow shown in FIG. 14.

First, resist liquid is ejected onto the center of the wafer W held on the spin chuck 302, and the spin chuck 302 is rotated to form a resist film on the wafer W.

Next, the laser irradiation unit 314 shown in FIG. 13 is moved to the peripheral edge of the wafer W to irradiate the laser. Normally, in EBR processing, an area from which unnecessary resist film is removed is set in advance in order to improve the yield of the wafer W. In the first embodiment described above, all of the resist film in that area is removed by laser irradiation, but in the third embodiment, only a portion of the unnecessary resist film is removed by laser irradiation.

FIG. 15 is an explanatory diagram showing the state of formation of a resist film on the wafer surface. The left side of FIG. 15 is the edge side of the wafer W, and the right side of the wafer W is the center side of the wafer W. As shown in FIG. 15(a), in the third embodiment, a region L _T other than the edge of the wafer W is set in advance in the peripheral portion of the wafer W, and the region L _T is irradiated with a laser. In this specification, the region L _T is referred to as a "target removal region." That is, in the EBR process in this embodiment, a laser is irradiated to the target removal region L _T of the resist film, and the resist film in the target removal region L _T is removed. The target removal region L _T is a region that is arbitrarily set in consideration of the yield of the wafer W, the discharge position of the solvent, and the like. Note that the target removal region L _T is preferably a region where a hump occurs due to contact between the solvent and the coating film when the resist film removal process (EBR process) of the wafer peripheral portion is performed using only the solvent. In other words, the target removal region L _T is preferably a region where the coating film does not completely dissolve upon contact with the solvent, and the hardness of the coating film becomes softer than before contact with the solvent. By irradiating the area with a laser and removing the resist film, the occurrence of humps can be effectively suppressed.

After the laser is irradiated onto the target removal region L _T shown in Fig. 15(a), the solvent discharge nozzle 343 is moved to the peripheral portion of the wafer W as shown in Fig. 15(b). At this time, the solvent discharge nozzle 343 is moved so that the solvent discharge position is near the boundary between the laser irradiation region L and the resist film R ₁ to be removed. Next, the solvent is discharged while rotating the spin chuck 302. Thereby, the unnecessary resist film R ₁ remaining outside the laser irradiation region is removed as shown in Fig. 15(c), completing the EBR process.

In the EBR process of this embodiment, the unnecessary resist film is removed using a solvent as in the conventional process, but in the process of discharging the solvent, there is a region L where no resist film is formed between the unnecessary resist film R ₁ and the resist film R ₂ necessary for pattern formation. Therefore, when discharging the solvent onto the unnecessary resist film R ₁ , the discharged solvent is unlikely to come into contact with the resist film R ₂ necessary for pattern formation, and the occurrence of humps and erosion in the resist film R ₂ can be suppressed.

In the EBR processing method of this embodiment, the protective film described in the first and second embodiments is not provided, but the protective film may be provided in the EBR processing of this embodiment. For example, if a protective film is formed on the upper surface of the resist film R before the laser irradiation shown in FIG. 15(a), debris generated by the laser irradiation will scatter on the upper surface of the protective film. Then, the debris is removed together with the protective film, so that no debris remains on the upper surface of the resist film R ₂ required for pattern formation. That is, if the resist coating device 31 according to the third embodiment is equipped with the processing liquid discharge mechanism 320 for forming the protective film (FIG. 4) and the removing liquid discharge mechanism 330 for removing the protective film (FIG. 5) described in the first embodiment, the occurrence of humps and erosion of the resist film can be suppressed and the effect of debris countermeasures can be obtained.

The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The above-described embodiments may be omitted, substituted, or modified in various ways without departing from the scope and spirit of the appended claims.

The substrate processing apparatus that performs the EBR process according to the present disclosure can also be used in processing substrates other than semiconductor wafers, such as FPD (flat panel display) substrates.

Reference Signs List 1 Substrate processing system 31 Resist coating device 40 Heat treatment device 200 Control unit 302, 402 Spin chuck 314 Laser irradiation unit 323 Processing liquid nozzle 333 Removal liquid nozzle R Resist film P Protective film W Wafer

Claims (10)

A substrate processing apparatus, comprising:
a substrate holding unit that holds and rotates a substrate on which a coating film for pattern formation has been formed;
a processing liquid discharge unit that discharges a processing liquid for forming a protective film on the substrate held by the substrate holding unit;
a laser irradiation unit that irradiates a laser onto a peripheral portion of the substrate on which the protective film is formed;
A solvent discharge unit that discharges a solvent;
a removal liquid discharge unit that discharges a removal liquid onto the protective film to remove the protective film;
A control unit that controls the operation of the laser irradiation unit and the solvent discharge unit ,
The control unit is configured to control the substrate processing apparatus to irradiate the laser onto a predetermined target removal area of the coating film and to eject the solvent onto the coating film remaining in an area radially outside the laser irradiation area . The substrate processing apparatus of claim 1, wherein the coating film is a resist film and the protective film is a water-soluble film. The substrate processing apparatus according to claim 1 or 2, wherein the laser is a solid-state laser having a wavelength of 240 nm or more. 1. A substrate processing system, comprising:
a coating treatment device that performs a coating treatment to form a coating film for forming a pattern on a substrate;
a heat treatment device for performing a heat treatment on the substrate and a substrate treatment device for removing the coating film from a peripheral portion of the substrate;
a control unit for controlling the coating treatment device, the heat treatment device, and the substrate treatment device,
The substrate processing apparatus includes:
a substrate holder that holds and rotates the substrate;
a processing liquid discharge unit that discharges a processing liquid for forming a protective film on the substrate held by the substrate holding unit;
a laser irradiation unit that irradiates a laser onto a peripheral portion of the substrate on which the protective film is formed;
A solvent discharge unit that discharges a solvent;
a removal liquid discharge unit that discharges a removal liquid onto the protective film to remove the protective film,
The control unit is configured to control the substrate processing system to alternately perform the coating process and the heating process two or more times to form two or more layers of the coating film on the substrate, eject the processing liquid onto the coating film to form the protective film on an upper surface of the coating film, irradiate the laser onto a predetermined target removal area of the coating film , eject the solvent onto the coating film remaining in an area radially outer than the laser irradiation area of the substrate, and eject the removal liquid onto the protective film remaining on the substrate irradiated by the laser. 5. The substrate processing system according to claim 4, wherein the coating film is a resist film, and the protective film is a water-soluble film. 6. The substrate processing system according to claim 4, wherein the laser is a solid-state laser having a wavelength of 240 nm or more. A method for processing a substrate, comprising:
A process of discharging a treatment liquid onto a substrate on which a coating film for pattern formation has been formed, to form a protective film on the substrate;
irradiating a peripheral portion of the substrate on which the protective film is formed with a laser;
and discharging a removal liquid onto the protective film remaining on the substrate irradiated with the laser, thereby removing the protective film .
In the laser irradiation step, the laser is irradiated onto a predetermined target removal area of the coating film, and a solvent is ejected onto the coating film remaining in an area radially outside the laser irradiation area of the substrate, in a substrate processing method . 8. The substrate processing method according to claim 7, wherein the coating film is a resist film, and the protective film is a water-soluble film. 9. The substrate processing method according to claim 7, wherein the laser is a solid-state laser having a wavelength of 240 nm or more. A readable computer storage medium storing a program that runs on a computer of a control unit that controls a substrate processing apparatus so as to cause the substrate processing apparatus to perform the substrate processing method according to any one of claims 7 to 9 .

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