CN114365264A - Substrate processing method - Google Patents

Abstract

A substrate processing method includes: a step of holding a substrate (WF) having a 1 st surface (S1) and a 2 nd surface (S2) opposite to the 1 st surface (S1); supplying a treatment liquid into which bubbles containing ozone gas and having a particle size of 50nm or less are mixed to a 2 nd surface (S2) of a Wafer (WF); and heating the processing liquid at a point of use for processing the substrate (WF).

Description

Substrate processing method

technical field

The present invention relates to a substrate processing method, and more particularly, to a substrate processing method using ozone gas.

Background technique

After the step of using the resist film on the wafer (substrate), the resist film is removed from the substrate in many cases. In particular, since the resist film used as the implantation mask for the ion implantation step is not easily removed, a cleaning solution having a strong effect is generally used. As a washing liquid having a strong effect, for example, sulfuric acid/hydrogen peroxide mixure (SPM) has been widely known from the past. However, in recent years, a substrate processing method that does not use SPM has been demanded due to the large burden of waste liquid treatment.

According to Japanese Patent Laid-Open No. 2008-153605, a substrate cleaning method using ozone water produced by a gas-liquid mixing method without addition of the substrate is disclosed. Here, the particle diameter R of the ozone bubbles contained in the ozone water is 0<R≦50 nm. Furthermore, it is disclosed to heat the generated ozone water before supplying it to the treatment tank. As a heating temperature, the range of 30 degreeC - 80 degreeC is illustrated. According to the above-mentioned gazette, the following first and second issues are proposed.

First, by suppressing the particle size to 50 nm or less, the buoyancy that the ozone bubbles receive from the ozone water is extremely small, so that the ozone bubbles are less likely to rise to the water surface. That is, it will remain in ozone water stably. There are also very few cases in which ozone bubbles that stably retain are degassed by impact when ozone water collides with a substrate or the like. These can achieve effective suppression of ozone degassing.

Second, washing can be efficiently performed by raising the temperature of the ozone water to an appropriate temperature for washing. Although the appropriate temperature may be affected by the nature of the object to be washed, the difference between partial washing or overall washing, the length of washing time, and the environment, a higher temperature is generally preferred. On the other hand, since ozone is easily dissolved when the water temperature is low, when ozone water is heated, degassing and thermal decomposition are likely to occur. On the other hand, since the particle size of the ozone bubbles contained in the ozone water is 50 nm or less, even if it expands by heating, the buoyancy it receives is small. Therefore, the ozone bubbles will still remain in the ozone water and will not be easily degassed. It is presumed that the ozone water can be raised to about 80°C because the particle size of the ozone bubbles is sufficiently small.

As described above, according to the above-mentioned publication, it is claimed that a sufficient cleaning effect can be obtained because degassing is not easy.

prior art literature

Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2008-153605

SUMMARY OF THE INVENTION

The problem to be solved by the invention

According to the research of the present inventors, in the technique described in the above-mentioned publication, when ozone water is used as a processing liquid without heating, the effect on the substrate is often insufficient. Although the effect becomes stronger if the ozone concentration is increased, the upper limit of the ozone concentration in the ozone water is usually about 80 ppm. Therefore, in order to promote ozone-based chemistry, it is desirable to heat to a certain temperature. In the technique of the above-mentioned publication, the heating of the ozone water as the treatment liquid is performed before the treatment liquid is supplied to the treatment tank. According to the study of the present inventors, in this case, it is difficult to maintain the state in which the ozone bubbles are dispersed in the treatment liquid at a high concentration until the point of use (POU: Point of Use) of the treatment liquid. As a result, the peculiar effect obtained by mixing minute ozone bubbles becomes small. Therefore, the effect of ozone-based treatment becomes weak.

The present invention was made in order to solve the above-mentioned problems, and an object thereof is to provide a substrate processing method capable of enhancing the action of ozone on the substrate.

technical solutions to problems

A first aspect is a substrate processing method comprising: the step of holding a substrate having a first surface and a second surface opposite to the first surface; the step of treating liquid of bubbles; and the step of heating the treating liquid at the point of use for treating the substrate. It should be noted that, in addition to the air bubbles having a particle diameter of 50 nm or less, air bubbles having a particle diameter exceeding 50 nm may be mixed into the treatment liquid.

In the second aspect, in the substrate processing method of the first aspect, the step of holding the substrate is performed so that the second surface of the substrate faces downward.

In the third aspect, in the substrate processing method of the first or second aspect, the step of heating the processing liquid includes the step of heating the substrate from the first surface.

In the fourth aspect, in the substrate processing method of the first or second aspect, the step of heating the processing liquid includes the step of heating the substrate from the second surface.

In the fifth aspect, in the substrate processing method of the first or second aspect, the step of heating the processing liquid includes the step of simultaneously heating the substrate from the first surface and the second surface.

A sixth aspect is the substrate processing method according to any one of the first to fifth aspects, wherein the step of supplying the processing liquid includes the step of discharging the processing liquid toward the second surface of the substrate.

A seventh aspect is the substrate processing method according to any one of the first to fifth aspects, wherein the step of supplying the processing liquid includes the step of immersing the second surface of the substrate in the processing liquid stored in the processing tank.

In an eighth aspect, in the substrate processing method of the seventh aspect, the step of immersing the second surface of the substrate is performed so that the first surface of the substrate is located above the liquid surface of the processing liquid.

In the ninth aspect, in the substrate processing method of the seventh or eighth aspect, the step of immersing the second surface of the substrate includes the step of sealing the processing tank in which the processing liquid is stored.

A tenth aspect is the substrate processing method according to any one of the first to ninth aspects, wherein the processing liquid contains water.

An eleventh aspect is the substrate processing method of the tenth aspect, wherein the processing liquid contains at least one of ammonia and hydrogen peroxide.

A twelfth aspect is the substrate processing method according to any one of the first to ninth aspects, further comprising the step of generating a processing liquid. The step of generating the treatment liquid includes a step of mixing bubbles having a particle diameter of 50 nm or less containing ozone gas into an aqueous solution containing ozone water.

A thirteenth aspect is the substrate processing method of the twelfth aspect, wherein the aqueous solution contains at least one of ammonia and hydrogen peroxide.

effect of invention

According to the first aspect, since the processing liquid is heated at the point of use, the temperature of the processing liquid can be kept low just before the point of use. Thereby, it becomes easy to maintain the state in which the ozone bubbles are dispersed in the processing liquid at a high concentration until the point of use. Therefore, ozone bubbles can be supplied to the second surface of the substrate at a high concentration. In addition, when the treatment liquid is heated at the point of use, the bubbles expand. Thereby, since the surface area of a bubble becomes large, it becomes easy for a bubble to come into contact with the 2nd surface of a board|substrate. A thin film of the processing liquid is formed between the air bubbles contacting the second surface of the substrate and the second surface of the substrate. This thin film of the treatment liquid has a higher ozone concentration by being adjacent to the air bubbles. Furthermore, the ozone of this thin film has a high temperature by the above-mentioned heating. Therefore, since ozone in the thin film of the treatment liquid has both a high concentration and a high temperature, the second surface of the substrate in contact with the thin film is strongly affected by ozone. As described above, the action of ozone on the substrate can be enhanced.

According to the second aspect, the processing liquid is supplied to the second surface facing downward of the substrate. As a result, the second surface of the substrate is positioned above the supplied processing liquid. Then, by heating the processing liquid, the micro-bubbles expand. Expanded air bubbles easily float in the treatment liquid. In other words, the air bubbles tend to move to the second surface of the substrate. This makes it easier for the air bubbles to come into contact with the second surface of the substrate. Therefore, the effect of ozone on the substrate can be further enhanced.

According to the third aspect, the step of heating the processing liquid includes the step of heating the substrate from the first surface. This makes it difficult for the adverse effects of heating to spread to the second surface.

According to the fourth aspect, the step of heating the processing liquid includes the step of heating the substrate from the second surface. Thereby, the 2nd surface which is the surface to be processed among the 1st surface and the 2nd surface can be heated preferentially.

According to the fifth aspect, the step of heating the processing liquid includes the step of simultaneously heating the substrate from the first surface and the second surface. Thereby, the 2nd surface which is the surface to be processed is easy to be fully heated.

According to the sixth aspect, the step of supplying the processing liquid includes the step of discharging the processing liquid toward the second surface of the substrate. Thereby, the processing liquid can be continuously supplied toward the second surface of the substrate again. Therefore, the weakening of the effect of ozone due to inactivation can be avoided.

According to the seventh aspect, the step of supplying the processing liquid includes the step of immersing the second surface of the substrate in the processing liquid stored in the processing tank. Accordingly, it is possible to ensure a longer time for the bubbles in the processing liquid to expand and move toward the second surface of the substrate.

According to the eighth aspect, the step of immersing the second surface of the substrate is performed so that the first surface of the substrate is positioned above the liquid level of the processing liquid. Thereby, the height of the 2nd surface of a board|substrate approaches the liquid surface where the density of bubbles tends to become high. Therefore, it is easier for the air bubbles to come into contact with the second surface of the substrate. Therefore, the effect of ozone on the substrate can be further enhanced.

According to the ninth aspect, the step of dipping the second surface of the substrate includes the step of sealing the processing tank in which the processing liquid is stored. Thereby, ozone cannot escape easily from a process liquid. Therefore, the effect of ozone on the substrate can be further enhanced.

According to the tenth aspect, the treatment liquid contains water. Thereby, ozone water can be made to act on a board|substrate.

According to the eleventh aspect, the treatment liquid contains at least one of ammonia and hydrogen peroxide. Thereby, the processing of a board|substrate can be accelerated|stimulated.

According to the twelfth aspect, the step of generating the treatment liquid includes the step of mixing the ozone gas-containing air bubbles with a particle diameter of 50 nm or less into the aqueous solution containing ozone water. Thereby, the effect|action of ozone on a board|substrate can be further strengthened.

According to the thirteenth aspect, the aqueous solution contains at least one of ammonia and hydrogen peroxide. Thereby, the processing of a board|substrate can be accelerated|stimulated.

Description of drawings

FIG. 1 is a block diagram schematically showing the configuration of a substrate processing system in Embodiment 1 of the present invention.

FIG. 2 is a block diagram schematically showing the configuration of a control unit included in the substrate processing system of FIG. 1 .

3 is a cross-sectional view schematically showing the configuration of the substrate processing apparatus in Embodiment 1 of the present invention.

4 is a flowchart schematically showing a substrate processing method in Embodiment 1 of the present invention.

5 is a cross-sectional view schematically showing the configuration of a substrate processing apparatus in Embodiment 2 of the present invention.

6 is a cross-sectional view schematically showing the configuration of a substrate processing apparatus in Embodiment 3 of the present invention.

Detailed ways

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. In addition, in the following drawings, the same reference number is attached|subjected to the same or equivalent part, and the description is not repeated.

(Embodiment 1)

FIG. 1 is a block diagram schematically showing the configuration of a substrate processing system in the first embodiment. The substrate processing system includes an indexer 310, an inversion mechanism 320, a central robot 330 (transport mechanism), a processing apparatus 101 (substrate processing apparatus), a processing apparatus 201, and a control unit 90 (controller).

The indexer 310 is a mechanism capable of sending and receiving wafers (substrates). The inversion mechanism 320 is disposed between the indexer 310 and the central robot 330, and inverts the wafer passing between them. The central robot 330 transfers wafers between the processing apparatuses 101 and 201 and the inversion mechanism 320 .

The processing apparatus 101 is a single-wafer type apparatus that can be used for processing to remove organic matter adhering to the wafer. Typically, the organic is a used resist film. This resist film can be used, for example, as an implantation mask for the ion implantation step.

The processing device 201 may be the same as or different from the processing device 101 . It should be noted that the number of processing apparatuses included in the substrate processing system is arbitrary.

FIG. 2 is a block diagram schematically showing the configuration of the control unit 90 ( FIG. 1 ). The control unit 90 can be constituted by a general computer having an electric circuit. Specifically, the control unit 90 includes a CPU (Central Processing Unit) 91 , a ROM (Read Only Memory) 92 , a RAM (Random Access Memory) 93 , a storage device 94 , and an input part 96 , display part 97 , communication part 98 , and bus 95 connecting them to each other.

The ROM 92 stores basic programs. The RAM 93 is used as a work area when the CPU 91 performs predetermined processing. The storage device 94 is constituted by a non-volatile storage device such as a flash memory or a hard disk device. The input unit 96 is composed of various switches, a touch panel, and the like, and receives input setting instructions such as processing recipes from the operator. The display unit 97 is composed of, for example, a liquid crystal display device, lamps, and the like, and displays various information under the control of the CPU 91 . The communication unit 98 has a data communication function via a LAN (Local Area Network) or the like. The storage device 94 is preset with a plurality of modes related to the control of each device constituting the substrate processing system ( FIG. 1 ). When the CPU 91 executes the processing program 94P, one of the above-described plural modes is selected, and each device is controlled by this mode. In addition, the processing program 94P may also be stored in a recording medium. When this recording medium is used, the processing program 94P can be installed in the control unit 90 . In addition, some or all of the functions executed by the control unit 90 are not necessarily realized by software, but may be realized by hardware such as a dedicated logic circuit.

FIG. 3 is a cross-sectional view schematically showing the configuration of the processing apparatus 101 . The processing apparatus 101 includes a processing liquid supply unit 121 , a heating unit 141 , and a holding unit 151 . In addition to the processing apparatus 101, the figure also shows the wafer WF (substrate) processed by this processing apparatus 101. The wafer WF has a back surface S1 (first surface) and a processing surface S2 (a second surface opposite to the first surface).

The treatment liquid supply unit 121 includes a deionized water (DIW: De-Ionized Water) source 21 , an ozone gas source 22 , a bubble generator 23 , and a treatment liquid nozzle 31 . The bubble generator 23 mixes ozone gas with deionized water. Thereby, the air bubbles with particle diameters of 50 nm or less containing ozone gas are mixed in the deionized water. Hereinafter, the air bubbles having such a particle diameter are also referred to as fine air bubbles. Typically, the particle size distribution of the fine air bubbles includes bubbles having a particle diameter of 1 nm or more, for example, particularly many bubbles of about 10 nm. Deionized water in which minute bubbles containing ozone gas are mixed is used as a treatment liquid in the treatment apparatus 101 . In addition, the process liquid may contain air bubbles with particle diameters exceeding 50 nm in addition to fine air bubbles. The processing liquid nozzle 31 has an upward tip, and as indicated by arrow D2 , discharges the processing liquid toward the processing surface S2 of the wafer WF.

The heating unit 141 has the lamp heater 41 . Lamp heater 41 emits light LT toward back surface S1 of wafer WF. By absorbing the light LT, the back surface S1 is heated. Therefore, it is preferable that the light LT contains light of a wavelength easily absorbed by the wafer WF. The lamp heater 41 preferably has a light emitting diode (LED: Light Emitting Diode).

Moreover, the heating part 141 may have the robot arm 56 which holds the lamp heater 41, the rotation shaft 57, and the rotation angle adjuster 58. The rotation angle adjuster 58 constituted by an actuator adjusts the rotation angle of the rotation shaft 57 as indicated by the arrow AG. The robot arm 56 extends radially from the rotation shaft 57 . When the rotation angle adjuster 58 operates, the position where the light LT from the lamp heater 41 is strongly received is scanned on the back surface S1. Thereby, the heating of the back surface S1 can be performed more uniformly.

In addition, the heating part 141 may have the warm water source 51 and the warm water nozzle 52 . The warm water nozzle 52 supplies warm water from the warm water source 51 to the back surface S1. The warm water on the back surface S1 relieves the rapid heating of the back surface S1 by the light LT. Thereby, warpage of the wafer WF due to uneven heating can be suppressed. The warm water nozzle 52 can be attached to the robot arm 56 , whereby the displacement of the lamp heater 41 and the displacement of the warm water nozzle 52 can be easily synchronized. In addition, you may use cold water (unheated water) instead of warm water. Alternatively, the warm water source 51 and the warm water nozzle 52 may be omitted.

The holding portion 151 includes the holding pin 11 , the rotating plate 61 , and the motor 65 . The holding pins 11 support the wafer WF. The rotating plate 61 supports the holding pins 11 . The motor 65 rotates the rotary plate 61 as indicated by the arrow RT. With this configuration, the wafer WF can be rotated. The processing liquid discharged as indicated by the arrow D2 spreads over the entire processing surface S2 as indicated by the arrow SR by centrifugal force due to the rotation of the wafer WF.

It should be noted that the operations of the above-described units included in the processing device 101 can be controlled by the control unit 90 ( FIG. 1 ).

Next, the wafer (substrate) processing method of the present embodiment will be described below.

Referring to step S10 ( FIG. 4 ), the indexer 310 ( FIG. 1 ) transports the wafer WF to the inversion mechanism 320 . At the time of sending to the inversion mechanism 320, the processing surface S2 of the wafer WF faces upward. Referring to step S20 ( FIG. 4 ), the wafer WF is turned over by the turning mechanism 320 so that the processing surface S2 of the wafer WF faces downward. The flipped wafer WF is transported to the processing apparatus 101 by the central robot 330 (FIG. 1).

Referring to step S30 ( FIG. 4 ), the holding pins 11 ( FIG. 3 ) hold the wafer WF (substrate). As a result of the above inversion, this holding is performed so that the processing surface S2 of the wafer WF faces downward. Next, the wafer WF is rotated by rotation (arrow RT) by the rotary plate 61 ( FIG. 3 ).

Referring to step S40 ( FIG. 4 ), the processing liquid nozzle 31 discharges the processing liquid in which the minute air bubbles containing ozone gas are mixed toward the processing surface S2 of the wafer WF (arrow D2 ). Thereby, the processing liquid is supplied to the processing surface S2 of the wafer WF. The supplied processing liquid is diffused over the entire processing surface S2 as indicated by the arrow SR by centrifugal force.

Referring to step S50 ( FIG. 4 ), wafer WF is heated from back surface S1 by heating unit 141 . Specifically, the back surface S1 of the wafer WF is heated by absorbing the light LT from the lamp heater 41 . The processing surface S2 is heated by heat conduction from the back surface S1. The treatment liquid is heated on the treatment surface S2 by heat conduction from the heated treatment surface S2. Preferably, the treatment liquid is heated to a temperature of 40° C. or higher and less than the boiling point, and more preferably, the treatment liquid is heated to a temperature close to the boiling point within this temperature range. The position on the processing surface S2 (in other words, the position directly below the processing surface S2 ) is a position where the processing liquid acts on the wafer WF, that is, a use point for processing the wafer WF. Therefore, by the above heating, the processing liquid is heated at the point of use for processing the wafer WF. When the heated processing liquid acts on the processing surface S2, the processing of the wafer WF is performed. Specifically, cleaning of the wafer WF, such as resist removal, is performed.

Referring to step S60 ( FIG. 4 ), after the above washing step, a washing step of the wafer WF is performed. The rinsing step can be performed either by the processing device 101 (FIG. 3) or by the processing device 201 (FIG. 1). When the processing apparatus 101 is used, the deionized water from the deionized water source 21 may be directly sent to the processing liquid nozzle 31 by the bubble generator 23 ( FIG. 3 ) without mixing with ozone gas. After the rinse step, the wafer WF is dried, eg by spin drying. The dried wafer WF is transported to the inversion mechanism 320 by the central robot 330 (FIG. 1).

Referring to step S70 ( FIG. 4 ), the wafer WF is turned over by the turning mechanism 320 ( FIG. 1 ), so that the processing surface S2 of the wafer WF faces upward again. Referring to step S80 ( FIG. 4 ), the indexer 310 ( FIG. 1 ) receives the wafer WF from the inversion mechanism 320 .

From the above, the processing of the wafer WF is completed.

According to the present embodiment, since the processing liquid is heated at the point of use, the temperature of the processing liquid can be kept low until just before the point of use. Thereby, it becomes easy to maintain the state in which the microbubbles of ozone are dispersed in the processing liquid at a high concentration until the point of use. Therefore, the fine air bubbles of ozone can be supplied to the processing surface S2 of the wafer WF at a high concentration. In addition, when the treatment liquid is heated at the point of use, the bubbles expand. Thereby, since the surface area of the air bubbles is increased, the air bubbles easily come into contact with the processing surface S2 of the wafer WF. A thin film of the processing liquid is formed between the air bubbles contacting the processing surface S2 of the wafer WF and the processing surface S2 of the wafer WF. This thin film of the treatment liquid has a higher ozone concentration by being adjacent to the air bubbles. Furthermore, the ozone of this thin film has a high temperature by the above-mentioned heating. Therefore, since the ozone in the thin film of the processing liquid has both a high concentration and a high temperature, the processing surface S2 of the wafer WF in contact with the thin film is strongly affected by the ozone. As described above, the effect of ozone on the wafer WF can be enhanced.

The processing liquid is supplied to the downward processing surface S2 of the wafer WF. As a result, the processing surface S2 of the wafer WF is positioned above the supplied processing liquid. Then, when the processing liquid is heated, the micro-bubbles expand. Expanded air bubbles easily float in the treatment liquid. In other words, the air bubbles tend to move to the processing surface S2 of the wafer WF. As a result, the air bubbles more easily come into contact with the processing surface S2 of the wafer WF. Therefore, the effect of ozone on the wafer WF can be further enhanced.

The heating of the processing liquid is performed by heating the wafer WF from the back surface S1. Thereby, the adverse effect of heating is less likely to spread to the processing surface S2. Specifically, since the light LT ( FIG. 3 ) from the lamp heater 41 is blocked by the wafer WF, it does not substantially reach the processing surface S2 . Thereby, the resist on the processing surface S2 can be prevented from being hardened by the photosensitive action of the light LT. Therefore, it is possible to prevent the resist from being hard to remove due to curing. Therefore, the effect of wafer processing can be improved.

The supply of the processing liquid is performed by discharging the processing liquid toward the processing surface S2 of the wafer WF. As a result, the processing liquid can be continuously supplied to the processing surface S2 of the wafer WF again. Therefore, the weakening of the effect of ozone due to inactivation can be avoided.

The treatment liquid contains water. Thereby, the ozone water can be made to act on the wafer WF.

(Variation of Embodiment 1)

The heating method of the wafer WF is not limited to the above-mentioned method. Wafer WF (FIG. 3) may also be heated from processing side S2 instead of back side S1. Thereby, the processing surface S2 which is the surface to be processed among the back surface S1 and the processing surface S2 can be heated preferentially. The heating from the processing surface S2 can be performed using the heater 43 (refer later-mentioned FIG. 6), for example. Alternatively, the wafer WF may be simultaneously heated from the back surface S1 and the processing surface S2. Thereby, the processing surface S2 is easy to be sufficiently heated.

The water in the treatment liquid may contain at least one of ammonia and hydrogen peroxide, or may contain both of them. Thereby, the processing of the wafer WF can be facilitated.

The treatment liquid can also be produced by preliminarily mixing minute air bubbles containing ozone gas into an aqueous solution containing ozone water. Therefore, it is only necessary to use the ozone water source instead of the deionized water source 21 . Thereby, the effect of ozone on the wafer WF can be further enhanced. Furthermore, the said aqueous solution may contain at least one of ammonia and hydrogen peroxide, and may contain both of them. Thereby, the processing of the wafer WF can be facilitated.

(Embodiment 2)

5 is a cross-sectional view schematically showing the configuration of the processing apparatus 102 (substrate processing apparatus) in the second embodiment. The processing apparatus 102 can be used instead of the processing apparatus 101 ( FIG. 3 : Embodiment 1) in the substrate processing system ( FIG. 1 ). The processing apparatus 102 includes a processing liquid supply unit 122 , a heater 42 as a heating unit, and a holding ring 12 as a holding unit for the wafer WF.

The processing liquid supply part 122 has the processing liquid introduction pipe 32 in place of the processing liquid nozzle 31 ( FIG. 3 : Embodiment 1), and further has the valve 24 and the processing tank 62 . The valve 24 is arranged between the processing liquid introduction pipe 32 and the bubble generator 23 . When the valve 24 is in the open state, the processing liquid introduction pipe 32 introduces the processing liquid into the processing tank 62 as indicated by the arrow IR. When the valve 24 is closed, the introduction of the treatment liquid from the treatment liquid introduction pipe 32 is stopped.

After the processing liquid has been sufficiently introduced, a region filled with the processing liquid is formed directly below the processing surface S2 of the wafer WF so as to contact the processing surface S2. This region is in a state in which the processing liquid does not leak out by members of the processing apparatus 102 (eg, the processing tank 62 and the processing liquid introduction pipe 32 ) and the wafer WF in the vertical direction, in other words, in a liquid-tight state. In particular, when the valve 24 is in the closed state, the region will be in a state in which neither leakage nor introduction of the treatment liquid occurs in the vertical direction.

The heater 42 as the heating unit may be, for example, a heat generating heater built into the processing tank 62 . The heater 42 faces the processing surface S2 of the wafer WF. Therefore, the wafer WF is heated from the processing surface S2 by the heater 42 . The holding ring 12 as the holding portion supports the wafer WF in the processing tank 62 .

Next, the wafer (substrate) processing method of the present embodiment will be described below mainly focusing on the differences of the first embodiment.

Referring to step S30 (FIG. 4), the holding ring 12 (FIG. 5) holds the wafer WF. This holding is performed so that the processing surface S2 of the wafer WF faces downward. Unlike the first embodiment, the present embodiment does not need to rotate the wafer WF.

Referring to step S40 ( FIG. 4 ), the treatment liquid introduction pipe 32 introduces the treatment liquid LP in which the minute air bubbles containing ozone gas are mixed into the treatment tank 62 (arrow IR). Thereby, the processing liquid LP is stored in the processing tank 62 . With the introduction of the processing liquid LP, the liquid level LS thereof rises, and finally reaches the processing surface S2 of the wafer WF. In other words, the processing surface S2 is immersed in the processing liquid LP stored in the processing tank 62 .

Referring to step S50 ( FIG. 4 ), wafer WF is heated from processing surface S2 by heater 42 as a heating unit. Specifically, the processing surface S2 of the wafer WF is heated by the heat radiation from the heater 42 . In addition, the processing liquid is heated on the processing surface S2 by the heat radiation from the heater 42 . The position on the processing surface S2 (in other words, the position directly below the processing surface S2 ) is the position where the processing liquid LP acts on the wafer WF, that is, the use point for processing the wafer WF. Therefore, by the above heating, the processing liquid LP is heated at the point of use for processing the wafer WF. The processing of the wafer WF is performed when the heated processing liquid LP acts on the processing surface S2. Specifically, the wafer WF is cleaned, for example, resist removal is performed.

The immersion of the above-mentioned processing surface S2 of the wafer WF is preferably performed so that the back surface S1 is located above the liquid level LS of the processing liquid LP. Such a positional relationship can be realized by causing the processing liquid LP to be in the height between the processing surface S2 and the back surface S1 as indicated by the arrow OF while continuously introducing the processing liquid into the processing tank 62 as indicated by the arrow IR during the immersion process. overflow as shown.

In addition, since the structure and method other than the above are substantially the same as those of the above-mentioned Embodiment 1 or its modification, the same or corresponding elements are given the same reference numerals and the description thereof will not be repeated.

Also in this embodiment, substantially the same effects as those in the first embodiment described above can be obtained. Furthermore, in this embodiment, unlike Embodiment 1 described above, the processing surface S2 of the wafer WF is immersed in the processing liquid LP stored in the processing tank 62 . Thereby, the flow of the processing liquid facing the processing surface S2 can be relaxed or substantially stopped. Therefore, it is possible to secure a longer time for the air bubbles expanded by the heating at the point of use to float. In other words, it is possible to ensure a longer time for the bubbles to move to the processing surface S2 of the wafer WF. As a result, the air bubbles more easily come into contact with the processing surface S2 of the wafer WF. Therefore, the effect of ozone on the wafer WF can be further enhanced.

The heating of the processing liquid LP is performed by heating the wafer WF from the processing surface S2. Thereby, the processing surface S2 which is the surface to be processed among the back surface S1 and the processing surface S2 can be heated preferentially.

When the immersion of the processing surface S2 of the wafer WF is performed so that the back surface S1 of the wafer WF is positioned above the liquid level of the processing liquid, the height of the processing surface S2 is close to the liquid level LS where the density of bubbles tends to increase. Therefore, the air bubbles are more likely to come into contact with the processing surface S2 of the wafer WF. Therefore, the effect of ozone on the wafer WF can be further enhanced.

(Variation of Embodiment 2)

The heating method of the wafer WF is not limited to the above-mentioned method. The wafer WF may be heated from the back surface S1 instead of the processing surface S2. The heating from the back surface S1 can be performed, for example, using the heating unit 141 ( FIG. 3 : Embodiment 1). Alternatively, the wafer WF may be simultaneously heated from the back surface S1 and the processing surface S2. Thereby, the processing surface S2 is easy to be sufficiently heated.

When the processing surface S2 of the wafer WF is immersed, the processing tank 62 in which the processing liquid LP is stored may be sealed. Thereby, ozone is less likely to escape from the treatment liquid LP. Therefore, the effect of ozone on the wafer WF can be further enhanced. The above-mentioned sealing can be obtained by, for example, not providing the gap GP between the edge of the processing tank 62 and the retaining ring 12 . For this purpose, a sealing member such as an O-ring may be provided between the edge of the processing tank 62 and the retaining ring 12 .

(Embodiment 3)

6 is a cross-sectional view schematically showing the configuration of the processing apparatus 103 (substrate processing apparatus) in the third embodiment. The processing apparatus 103 can be used in place of the processing apparatus 101 ( FIG. 3 : Embodiment 1) in the substrate processing system ( FIG. 1 ), and the inversion mechanism 320 is not required in this case.

The processing apparatus 103 includes a processing liquid supply unit 123 , a heater 43 serving as a heating unit, and a holding unit 153 . The processing liquid supply unit 123 has the processing liquid nozzle 33 instead of the processing liquid nozzle 31 ( FIG. 3 : Embodiment 1). The processing liquid nozzle 33 has a downward tip, and discharges the processing liquid toward the processing surface S2 of the wafer WF as indicated by the arrow D2.

Heater 43 serving as a heating unit radiates heat toward back surface S1 of wafer WF as indicated by arrow RD. Thereby, the back surface S1 is heated. By sufficiently increasing the size of the heater 43, even if the scanning operation of the heater as described in the first embodiment is not performed, a certain degree of uniformity of heating can be ensured.

The holding portion 153 has the holding pin 11 , the rotating ring 63 , and the motor 65 . The rotating ring 63 supports the holding pins 11 . The motor 65 rotates the rotating ring 63 . With this configuration, the wafer WF can be rotated as indicated by the arrow RT. The processing liquid discharged as indicated by the arrow D2 spreads over the entire processing surface S2 as indicated by the arrow SR by centrifugal force due to the rotation of the wafer WF.

In the wafer (substrate) processing method using the processing apparatus 103, the wafer WF is held so that the processing surface S2 faces upward. Further, when the processing liquid is heated, the wafer WF is heated from the back surface S1.

It should be noted that the configurations and methods other than those described above are substantially the same as those of the above-described first embodiment or its modifications, and therefore the same or corresponding elements are given the same reference numerals and will not be described repeatedly.

According to this embodiment, as in Embodiment 1, since the processing liquid is heated at the point of use, the temperature of the processing liquid can be kept low until just before the point of use. Thereby, it becomes easy to maintain the state in which the ozone bubbles are dispersed in the processing liquid at a high concentration until the point of use. Therefore, ozone bubbles can be supplied to the processing surface S2 of the wafer WF at a high concentration. Then, the bubbles expand when the treatment liquid is heated at the point of use. Thereby, since the surface area of the air bubbles is increased, the air bubbles easily come into contact with the processing surface S2 of the wafer WF. A thin film of the processing liquid is formed between the air bubbles in contact with the processing surface S2 of the wafer WF and the processing surface S2 of the wafer WF. This thin film of the treatment liquid has a higher ozone concentration by adjoining the air bubbles. In addition, the ozone of the film has a higher temperature by the above-mentioned heating. Therefore, since the ozone in the thin film of the processing liquid has both a high concentration and a high temperature, the processing surface S2 of the wafer WF in contact with the thin film is strongly affected by the ozone. Thereby, the action of ozone on the wafer WF can be enhanced.

(Variation of Embodiment 3)

The heating method of the wafer WF is not limited to the above-mentioned method. The wafer WF may also be heated from the processing surface S2 instead of the back surface S1. Thereby, the processing surface S2 which is the surface to be processed among the back surface S1 and the processing surface S2 can be heated preferentially. Alternatively, the wafer WF may be simultaneously heated from the back surface S1 and the processing surface S2. Thereby, the processing surface S2 is easy to be sufficiently heated.

Although the present invention has been described in detail, the above-mentioned description is merely an example in all aspects, and the present invention is not limited thereto. Countless modifications not illustrated can be understood as being conceivable without departing from the scope of the present invention. The respective configurations described in the above-described respective embodiments and respective modified examples may be appropriately combined or omitted unless they contradict each other.

Symbol Description

11: Hold pin

12: Holding Ring

21: Deionized water source

22: Ozone gas source

23: Bubble Generator

24: Valve

31, 33: Treatment Fluid Nozzle

32: Treatment liquid introduction tube

41: Lamp heater

42,43: Heater

51: Warm water source

52: Warm water nozzle

56: Robot Arm

57: Rotary axis

58: Rotation angle adjuster

61: Rotary plate

62: Processing tank

63: Swivel Ring

65: Motor

90: Control Department

101 to 103: Processing equipment (substrate processing equipment)

121 to 123: Treatment liquid supply part

141: Heating section

151, 153: Retention Department

LP: Treatment liquid

S1: Back (Side 1)

S2: Processing side (2nd side)

WF: Wafer (substrate).

Claims (13)

1. A substrate processing method includes:

a step of holding a substrate having a 1 st surface and a 2 nd surface opposite to the 1 st surface;

supplying a treatment liquid containing bubbles having a particle size of 50nm or less containing ozone gas to the 2 nd surface of the substrate; and

heating the treatment liquid at a point of use for performing the treatment of the substrate.

2. The substrate processing method according to claim 1, wherein the step of holding the substrate is performed such that the 2 nd surface of the substrate faces downward.

3. The substrate processing method according to claim 1 or 2, wherein the step of heating the processing liquid comprises a step of heating the substrate from the 1 st surface.

4. The substrate processing method according to claim 1 or 2, wherein the step of heating the processing liquid comprises a step of heating the substrate from the 2 nd surface.

5. The method of claim 1 or 2, wherein the step of heating the processing liquid comprises simultaneously heating the substrate from the 1 st surface and the 2 nd surface.

6. The substrate processing method according to any one of claims 1 to 5, wherein the step of supplying the processing liquid comprises a step of discharging the processing liquid toward the 2 nd surface of the substrate.

7. The substrate processing method according to any one of claims 1 to 5, wherein the step of supplying the processing liquid comprises a step of immersing the 2 nd surface of the substrate in the processing liquid stored in a processing tank.

8. The substrate processing method according to claim 7, wherein the step of immersing the 2 nd surface of the substrate is performed such that the 1 st surface of the substrate is positioned above a liquid surface of the processing liquid.

9. The substrate processing method according to claim 7 or 8, wherein the step of immersing the 2 nd surface of the substrate includes a step of sealing a processing tank in which the processing liquid is stored.

10. The substrate processing method according to any one of claims 1 to 9, wherein the processing liquid contains water.

11. The method of claim 10, wherein the processing liquid comprises at least one of ammonia and hydrogen peroxide.

12. The substrate processing method according to any one of claims 1 to 9, further comprising: a step of generating the treatment liquid; the step of generating the treatment liquid includes a step of mixing bubbles having a particle size of 50nm or less containing ozone gas into an aqueous solution containing ozone water.

13. The method of claim 12, wherein the aqueous solution comprises at least one of ammonia and hydrogen peroxide.

Images