JP2001347211A - Method and apparatus for treating substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate treating method and an apparatus having a chemical liquid feed nozzle capable of feeding a treatment liquid with low impacts on a substrate. SOLUTION: The treating apparatus including a substrate holding part 4 to rotatably horizontally hold a treating substrate 3, a slit shaped chemical liquid delivery part 2 to feed chemical liquids to the substrate 3 from a chemical liquid tank, and a drive part 1 to move the chemical liquid delivery part 2 is used to continuously move and feed the chemical liquid, in a thin film state, onto the surface of the treating substrate 3 which is rotated during the treatment. Since the chemical liquid is fed from a slit like delivery port onto the treating substrate which is horizontally held and rotated, the liquid can be efficiently replaced, while an impact on the film is being suppressed, and hence machining accuracy can be improved, while defects can be reduced. Further, since a slit nozzle, wherein a slit or R type groove having a length larger than the diagonal or diameter of the treating substrate is provided, is used, the chemical liquid can be supplied onto wider area than the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a processing method and a processing apparatus for performing a surface treatment on a substrate such as a semiconductor substrate or a glass substrate, and more particularly, to a discharge port (nozzle) for supplying a chemical solution onto the substrate. It is about structure.

[0002]

2. Description of the Related Art In a semiconductor device or a liquid crystal display, various processes are performed on a substrate, and finally a fine pattern is formed to add a desired function. When such a substrate is processed, not only a dry process using a gas but also a wet process using a chemical solution is widely used. For example, a wet process is used in a developing process for forming a photosensitive resin pattern used for processing a fine pattern. In the case of forming a photosensitive resin pattern, first, a photosensitive resin is applied onto a film to be processed formed on a silicon or quartz substrate, and the photosensitive resin in a desired region is exposed using an exposure mask. . Next, the developing step is a step of forming a photosensitive resin pattern by removing a photosensitive portion in a positive type or an unexposed portion in a negative type using a developing solution, for example, an organic solvent or an alkaline aqueous solution. Also, in the case of processing a chrome mask for exposure, a wet process is used on the chromium film. In this case, after forming a chromium film on a quartz substrate, a photosensitive resin pattern is formed, and the chromium film exposed from the photosensitive resin pattern is isotropically wet-etched using a ceric ammonium nitrate solution or the like.

Also, prior to processing, a mixed chemical solution of sulfuric acid and hydrogen peroxide is used to remove unnecessary organic substances adhering to a substrate or to remove a photosensitive resin pattern remaining after etching. Have been. The natural oxide film formed by the reaction between oxygen in the air and the silicon substrate is also removed by using NH ₄ F or diluted HF as a chemical solution to prevent uniform processing. Further, when depositing gold on a silicon wafer, an Au plating solution is used.

[0004]

As a wet process, there are a dipping method in which a substrate is immersed in a chemical solution, and a spray or paddle method in which a chemical solution is supplied to the surface of the substrate for processing. In the dipping method, a large amount of a chemical solution is required to sufficiently immerse the substrate, and there is contamination from or on the back surface. In the conventional spray or paddle method, the chemical is supplied from above the substrate. In this method, the chemical distribution is distributed between the center and the periphery of the substrate,
Or the rotation of the substrate causes a tendency for the chemical solution to flow around the substrate due to the centrifugal force.On the contrary, there is a tendency for the chemical solution to collect at the center. Accuracy has been reduced. Further, in the developing process which is one of the wet processes, when these spray or paddle methods are used, in the former case, the supply pressure of the chemical solution to the photosensitive resin film is large, and the film is peeled off and the unexposed portion is shaved. It may re-adhere to the exposed area and induce defects.In the latter case, the replacement of the old chemical with the new chemical in the exposed area is difficult to proceed, resulting in a difference in the development speed depending on the pattern density, resulting in a decrease in dimensional accuracy. It was causing deterioration.

Japanese Patent Application Laid-Open No. 7-36195 proposes a method of supplying a chemical solution to a substrate surface while horizontally moving a chemical solution supply section from one of the substrates. With this method, it is possible to reduce the pressure of supplying the chemical solution to the film surface. There are many developments of this method, and in these methods, a discharge port having a width substantially equal to that of the processing substrate is provided, and the liquid is discharged obliquely rearward with respect to the moving direction of the liquid supply section. ing. However, this method is still insufficient in terms of liquid replacement between the reacted old chemical liquid and the newly supplied fresh chemical liquid, and it cannot be denied that there is a variation in processing accuracy. In Japanese Patent Application Laid-Open No. 9-138508, an attempt is made to further reduce the pressure of the supply liquid on the film surface by providing a discharge port on the substrate rotation direction side and moving the chemical liquid supply unit in the substrate rotation direction. However, in this method, it is difficult to control the balance of the supply amount of the chemical solution from the discharge port, and there is a difference between the central portion where the amount of the chemical solution on the substrate surface is easily collected by the rotation of the substrate and the peripheral portion which easily flows to the outer periphery due to centrifugal force. Will be.
As described above, in the conventional wet process, it is difficult to uniformly supply the chemical solution to the entire substrate, and further, the processing accuracy and the uniformity are deteriorated, and this has been a trigger of the occurrence of defects. The present invention has been made in view of such circumstances, and provides a substrate processing method having a chemical liquid supply nozzle capable of supplying a processing liquid with low impact, and a substrate processing apparatus for performing the method.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a substrate holder for horizontally rotating and holding a processing substrate, and supplying a chemical solution from the chemical solution tank to the held processing substrate. Using a processing apparatus provided with a slit-shaped chemical liquid discharge section and a drive section for moving the chemical liquid discharge section, the chemical liquid is continuously supplied to the surface of the processing substrate rotating during the processing while moving in a thin film form. It is characterized by. Further, as a means for discharging the chemical solution in a slit shape, a slit nozzle longer than the diagonal or diameter of the processing substrate or a nozzle having an R-shaped groove inside the nozzle is used. According to the present invention, a chemical solution is continuously supplied in a thin film form from a slit-shaped discharge port onto a horizontally held / rotated processing substrate, so that liquid replacement can be performed efficiently while suppressing impact on the film surface. Processing accuracy can be improved. It is also effective in reducing defects. Furthermore, a chemical liquid can be supplied larger than the width of the processing substrate by a slit nozzle provided with a slit or an R-shaped groove longer than the diagonal or diameter of the processing substrate, so that the in-plane uniformity can be improved.

That is, the substrate processing method of the present invention is characterized in that a substrate to be processed is held horizontally, and a chemical solution is continuously supplied to the surface of the substrate from a slit-like discharge port in the form of a thin film while rotating the substrate. And The supply of the chemical solution may be continued throughout the processing of the surface of the substrate to be processed with the chemical solution. The processing of the substrate to be processed may be a developing process of a photoresist formed on the surface of the substrate to be processed. The substrate processing apparatus of the present invention holds a substrate to be processed horizontally, and means for rotating, a slit-shaped discharge port for supplying a chemical solution for supplying a chemical solution in a thin film form, and a slit-shaped discharge port for supplying the chemical solution. And a means for fixing or moving, and implementing any of the substrate processing methods described above. The slit-shaped discharge port for supplying a chemical solution may have a longitudinal direction longer than a diagonal or a diameter of the substrate to be processed. The slit-shaped discharge port for supplying a chemical solution may be connected to a number of chemical solution supply tubes each having a flow rate adjustable valve on the upstream side. A liquid reservoir for absorbing shock due to pressure may be provided in the slit-shaped discharge port for supplying the chemical liquid.
The slit-shaped discharge port for supplying the chemical solution may have a groove having a radius of curvature therein. The gap of the groove may be narrowed as approaching the slit of the slit-like discharge port for supplying the chemical solution.

[0008]

Embodiments of the present invention will be described below with reference to the drawings. First, referring to FIG. 1 and FIG.
An example will be described. FIG. 1 is a schematic sectional view of a substrate processing apparatus for supplying a chemical such as a developing solution, and FIG. 4 is a schematic plan view of the substrate processing apparatus of FIG. 1 as viewed from above. As shown in FIG. 1, a substrate processing apparatus includes a holding unit 1 used as a nozzle holding and moving guide, a slit-shaped nozzle 2 supported by the holding unit 1, and a process of receiving a supply of a chemical solution from the slit-shaped nozzle 2. A substrate holding chuck 4 for supporting the substrate 3,
A rotation mechanism 5 that supports the substrate holding chuck 4 and rotates the processing substrate 3 and a holding unit 1 that holds the slit nozzle 2
And a rotation mechanism 7 for freely rotating. The processing substrate 3 used here is used for developing a semiconductor wafer such as silicon or a substrate such as a liquid crystal used for manufacturing a semiconductor device, a photoresist for patterning a film formed on a wafer or a liquid crystal substrate, or an electron beam (EB) resist. The target is a mask substrate to be used. A mask substrate is drawn on the processing substrate 3 shown in FIG. The processing substrate 3 is arranged close to the slit nozzle 2 for supplying a chemical such as a developer. The slit-shaped nozzle 2 is connected via a holding unit 1 to a rotating mechanism 7 that moves. The slit nozzle 2 is supported by the holding unit 1. A chemical liquid supply line (not shown) from the chemical liquid tank is connected to the slit nozzle 2.

As shown in FIG. 4, a slit-shaped nozzle 2 "
Is located at a position where the liquid medicine is not discharged. In this state, the nozzle has been retracted to a position away from the substrate installation section. Simultaneously with the start of the processing, the slit-shaped nozzle 2 moves to a position which is a substrate end of the rotating processing substrate 3 separated from the retreat position and starts discharging the chemical solution in a thin film shape. The slit-shaped nozzle 2 continues reciprocating at a desired angle, for example, 40 ° from the discharge start position. The slit-shaped nozzle 2 ″ is disposed at a predetermined position of the reciprocating nozzle. At this time, the distance between the surface of the processing substrate 3 and the discharge port of the slit-shaped nozzle 2 is desirably 3 to 15 mm. The liquid is supplied in the form of a thin film and the distance between the discharge port and the surface of the processing substrate 3 is shortened to prevent liquid repellency and air bubbles from being caught by the discharge. Old chemicals gathered in the center and hindered the subsequent reaction, deteriorating in-plane uniformity.However, the amount of chemical supply can be increased by setting the nozzle operation angle from the substrate edge to the center. For example, when this method is applied to a developing process after photoresist exposure, the variation in the amount of reduction in the in-plane film of the photoresist is reduced by applying the method of this embodiment. It applied before those ± was 6nm is ± 3
nm.

Next, a second embodiment will be described with reference to FIGS. FIG. 2 is a perspective view of a slit-shaped nozzle in which the flow rate of the substrate processing apparatus can be adjusted, and a cross-sectional view of a portion along a line AA ′ in the perspective view. FIG. 5 moves on a wafer as a processing substrate. It is a top view of a slit-shaped nozzle. Conventionally, in a substrate processing apparatus, a chemical solution is supplied onto a rotating processing substrate as described above. In a conventional substrate processing apparatus, an old chemical solution that has been reacted is gathered at the center by the rotation of the processing substrate, hindering the subsequent reaction and deteriorating the in-plane uniformity. Uniformity can also be avoided by using the slit nozzle shown in FIG. The substrate processing apparatus having the slit-shaped nozzle includes a holding unit used as a nozzle holding and moving guide, a slit-shaped nozzle supported by the holding unit,
A substrate holding chuck that supports a processing substrate that receives a supply of a chemical solution from the slit nozzle, a rotation mechanism that supports the substrate holding chuck and rotates the processing substrate, and a rotation mechanism that freely rotates a holding unit that holds the slit nozzle. I have it. The processing substrate used here is a semiconductor wafer such as silicon used in the manufacture of semiconductor devices, a substrate such as a liquid crystal, a photoresist for patterning a film formed on a wafer or a liquid crystal substrate, or a mask substrate used for developing an EB resist. It is intended for.

A slit-shaped nozzle 2 for supplying a chemical such as a developing solution shown in FIG. 2 is arranged close to a processing substrate such as a wafer 17. The slit-shaped nozzle 2 is connected via a holding unit to a rotating mechanism that moves. The slit nozzle 2 is connected to a chemical supply line 15 from the chemical tank. This slit-shaped nozzle 2
A plurality of chemical supply lines 15 to the nozzle are divided from the flow meter. For example, twelve lines are connected to the discharge ports (slits) 14 of the slit-shaped nozzle 2 as shown. As shown in the cross-sectional view, the discharge port 14 of the slit-shaped nozzle 2 is connected to a chemical supply line 15 via a connection portion 16. With such a configuration, it is possible to partially control the discharge amount of the chemical solution. That is,
One supply line is installed from the chemical solution tank to the outside of the processing tank, and after dividing into six, each supply line is connected to each valve 61 to 66 and each flow meter 191 to 196, and this supply line is connected to the nozzle 2 Is divided into two just before and a total of 12
The chemical supply line 15 is connected to the slit nozzle 2. At this time, it is possible to equalize the flow rate and the pressure of the chemical supplied to the slit nozzle 2 by making the line lengths after the flow meter uniform. By using such a method, even when the nozzle length becomes long, the chemical solution can be uniformly supplied to the nozzle, and as a result, the amount of the chemical solution discharged through the nozzle can be made uniform.

Also, as shown in FIG. 5, by combining the divided lines in order from the outside, the flow rate limiting function can be effectively used in the following cases.
In this case, the line discharge ports 151 to 158 are arranged so as to share one chemical supply line 15 with the corresponding line discharge ports 151 ′ to 158 ′. When the in-plane distribution of the chemical liquid supply differs due to the rotation of the processing substrate, for example, when the number of rotations of the substrate is large in the developing process, the chemical liquid flows out of the processing substrate in the peripheral portion, and the chemical liquid supply is insufficient. In addition, by increasing the flow rate of the supply line to the outer peripheral portion of the nozzle and controlling the supply amount so as to reduce the central portion, the chemical solution is supplied to the processing surface (for example, the line discharge ports 156 and 156 ′). It is possible to improve the processing uniformity after the processing by minimizing the supply amount of the chemical solution and increasing the supply amount as the line discharge port (152 or the like) near the wafer 17) increases. During the process, the supply of the chemical solution at the line discharge port that does not require the supply of the chemical solution can be stopped. When the above method was applied to the development process of reticle manufacturing, the uniformity of the resist dimensions after processing was reduced to 20%.
% Could be improved. Further, the number of defects could be reduced to about 2/3 by reducing the impact of supplying the chemical solution to the film surface.

Next, a third embodiment will be described with reference to FIG. This embodiment is characterized by the shape of the slit nozzle. FIG. 3 is a perspective view of a slit-shaped nozzle of the substrate processing apparatus and a cross-sectional view illustrating the inside of the nozzle. Conventionally, in a substrate processing apparatus, a chemical solution is supplied onto a rotating processing substrate as described above. The substrate processing apparatus provided with the slit-shaped nozzle supports a holding portion used as a nozzle holding and moving guide, a slit-shaped nozzle supported by the holding portion, and a processing substrate receiving a supply of a chemical solution from the slit-shaped nozzle. And a rotating mechanism for supporting the substrate holding chuck and rotating the processing substrate and rotating a holding unit for holding the slit-shaped nozzle. The processing substrate used here is a semiconductor wafer such as silicon used in the manufacture of semiconductor devices, a substrate such as a liquid crystal, a photoresist for patterning a film formed on a wafer or a liquid crystal substrate, or a mask substrate used for developing an EB resist. It is intended for.
The slit-shaped nozzle for supplying a chemical such as a developing solution shown in FIG. 3 is arranged close to a processing substrate such as a wafer. The slit-shaped nozzle is connected via a holding unit to a rotating mechanism that moves. The slit-shaped nozzle is connected to a chemical solution supply line from a chemical solution tank.

As shown in FIG. 3 (a), the slit-shaped nozzle has a discharge port (slit) at the tip end, and a screw 8 for adjusting the clearance of the groove in the nozzle is provided at a peripheral portion above the discharge port.
Is attached, and the supply state of the chemical solution can be appropriately adjusted by the gap adjusting screw. FIG. 3 (b)
As shown in the figure, on the inner wall between the connection part 10 of the slit-shaped nozzle and the chemical solution supply line connected thereto and the discharge port 12, a fan-shaped groove with an R is opposed to each other (a groove in the nozzle). 11 are formed and arranged. The chemical is supplied from a connection portion 10 with the chemical supply line, and the inside of the groove 11 is used as a passage for the chemical. Furthermore, by gradually processing the groove 11 from the chemical solution supply line connection portion 10 to the slit-shaped discharge port 12 side, the liquid discharged from the discharge port (slit) can have the width of the slit according to the R in the slit. The ejection film is formed in a shape that spreads out from the fan. According to this method, the impact of the chemical solution on the surface of the processing substrate is suppressed as compared with the conventionally used chip type spray, and low defect processing without splashing of liquid or scattering of unexposed portion resist is achieved. It has become possible.

As shown in FIG. 3 (c), the inner wall from the connection portion 18 between the slit-shaped nozzle and the chemical supply line connected thereto to the discharge port 13 has a tapered groove 1.
9 are formed and arranged. The chemical is supplied from a connection portion 18 with the chemical supply line, and the inside of the groove 19 is used as a passage for the chemical. Further, by gradually processing the groove 19 from the chemical solution supply line connecting portion 18 to the slit-shaped discharge port 13 side, the liquid discharged from the discharge port (slit) is uniform according to the shape of the slit inner wall. An excellent discharge film is formed. According to this method, the impact of the chemical solution on the surface of the processing substrate is suppressed as compared with the conventionally used chip type spray, and low defect processing without splashing of liquid or scattering of unexposed portion resist is achieved. It has become possible. The present invention is not limited to the post-exposure development processing steps described in the above embodiments, but also includes an etching step by a wet process for a semiconductor substrate or a liquid crystal substrate, a cleaning step for removing organic and inorganic substances, and a residue after the etching processing. It can also be applied to processing such as a step of removing the photosensitive resin.

[0016]

As described above, according to the present invention, a chemical solution is continuously supplied in the form of a thin film from a slit-shaped discharge port to the surface of a processing substrate which is held horizontally while being rotated. The impact on the film surface is small, and the replacement of the chemical solution can be performed efficiently. Further, by uniformly supplying the chemical solution over the entire width of the processing substrate, it is possible to improve uniformity and reduce defects in the surface of the processing substrate.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view of a substrate processing apparatus for supplying a chemical such as a developer according to the present invention.

FIG. 2 is a schematic perspective view of a substrate processing apparatus provided with a slit-shaped nozzle having a plurality of pipes capable of adjusting a flow rate according to the present invention, and a cross-sectional view taken along a line AA ′ in the perspective view.

FIG. 3 is a perspective view and a schematic sectional view of a slit-shaped nozzle of the substrate processing apparatus of the present invention.

FIG. 4 is a schematic plan view of the substrate processing apparatus of FIG. 1 as viewed from above.

FIG. 5 is a plan view of a slit nozzle that moves on a processing substrate (wafer) according to the present invention.

[Explanation of symbols]

1 ... Nozzle holding and moving guide, 2, 2 ', 2 "
..Slit-shaped nozzles, 3 ... Processed substrates, 4 ...
· Substrate holding chuck, 5 · · · Rotating mechanism having substrate holding, 7 · · · Rotating mechanism, 8 · · · Screw for adjusting the gap in the nozzle groove, 9, 12, 13, 14 · · · Discharge port (slit Part), 10, 16, 18 ... connection part between slit-shaped nozzle and chemical solution supply line, 11 ... groove with R inside nozzle, 15 ... chemical solution supply line, 17
..Wafer, 19 ... tapered groove, 61-
66 ... Valve, 151-156, 151'-15
6 '... line discharge port, 191-196 ... flow meter.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) B05D 7/00 B05D 7/00 H 5F046 B08B 3/02 B08B 3/02 B G03F 7/30 502 G03F 7 / 30 502 7/38 501 7/38 501 H01L 21/027 H01L 21/30 569C (72) Inventor Yukio Obata 1st station, Komukai Toshiba-cho, Saiwai-ku, Kawasaki-shi, Kanagawa Prefecture F-term in Toshiba Microelectronics Center Reference) 2H096 AA25 AA30 CA01 GA30 GA31 3B201 AA03 AB01 AB34 AB42 BB22 BB32 BB92 CB01 4D075 AC64 AC93 AC94 BB20Z BB65Z CA47 DA08 DB14 DC22 EA05 4F041 AA06 AB01 BA05 BA34 BA56 4F042 AA07 BA08 BA12 BA12 EB12 LA12

Claims (9)

[Claims] 1. A substrate processing method, wherein a substrate to be processed is held horizontally, and while the substrate to be processed is rotated, a chemical solution is continuously supplied in a thin film form from a slit-shaped discharge port to the surface thereof. 2. The substrate processing method according to claim 1, wherein the supply of the chemical solution is continued while the surface of the substrate to be processed is processed by the chemical solution. 3. The substrate processing method according to claim 1, wherein the processing of the substrate to be processed is a developing process of a photoresist formed on a surface of the substrate to be processed. 4. A means for horizontally holding and rotating a substrate to be processed, a slit outlet for supplying a chemical solution for supplying a chemical solution in a thin film, and a fixed or movable slit outlet for supplying the chemical solution. 4. A substrate processing apparatus, comprising: means for performing the substrate processing method according to claim 1. 5. The substrate processing apparatus according to claim 4, wherein a longitudinal direction of the slit-shaped discharge port for supplying the chemical liquid has a slit shape longer than a diagonal or a diameter of the substrate to be processed. 6. The slit discharge port for supplying a chemical solution,
The substrate processing apparatus according to claim 4, wherein the substrate processing apparatus is connected to a number of chemical liquid supply tubes each having a flow rate adjustable valve on an upstream side. 7. The substrate processing apparatus according to claim 4, wherein a liquid reservoir for absorbing a shock by pressure is provided in the slit-shaped discharge port for supplying the chemical liquid. 8. The slit-like discharge port for supplying a chemical solution,
The substrate processing apparatus according to claim 4, further comprising a groove having a radius of curvature therein. 9. The substrate processing apparatus according to claim 8, wherein a gap of the groove is narrowed as approaching a slit portion of the slit outlet for supplying the chemical solution.