JP2003174006A - Substrate treating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate treating device that can reduce the feed rate of an inert gas, such as nitrogen gas, by surrounding the whole surface to be treated of a substrate with an atmosphere of the inert gas and, at the same time, preventing formation of a turbulent flow of the inert gas in the periphery of the substrate. <P>SOLUTION: This substrate treating device is provided with a substrate holding section 1 which rotates the substrate W while holding the substrate W, a first treating liquid supply section 3 which supplies a treating liquid to the surface to be treated of the substrate W held by the holding section 1, and an inert gas supply section 2 which is provided over the holding section 1 and forms a down flow of the inert gas so as to cover the whole surface to be treated of the substrate W. This device is also provided with a housing 5 housing the holding section 1, first treating liquid supply section 3, and inert gas supply section 2. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate processing apparatus for performing various kinds of processing on substrates such as semiconductor wafers, glass substrates and liquid crystal panels, and more particularly to various types of processing such as etching, cleaning, rinsing and drying. The present invention relates to a substrate processing apparatus that performs processing.

[0002]

2. Description of the Related Art A semiconductor device is manufactured by starting from a silicon substrate and repeating various steps such as film formation, mask pattern formation by lithography, etching, and subsequent heat treatment. And, cleaning is always performed at the end of one process or the beginning of the next process. The purpose of cleaning in the manufacture of semiconductor devices is to remove various contaminants from the substrate surface. As device miniaturization progresses, the contamination of the substrate surface directly affects the reliability and yield of the device, and the removal of fine particles and a trace amount of metal contamination becomes an important issue. In the cleaning process, generally, wet air treatment such as scrub cleaning or chemical cleaning in which clean air in a clean room is taken into a cleaning device and cleaning is performed while supplying a cleaning liquid such as a chemical solution to the substrate surface in the clean air. As described above, after the substrate is cleaned with the cleaning liquid, the rinsing step and the drying step are performed, and the drying step is the finishing of the cleaning and is the most important.

The most common method is spin drying, but problems such as dust generation from the apparatus itself and particle scattering due to turbulence of the air flow due to high speed rotation, and "stains" called watermarks remain on the surface. It has been pointed out. The watermark is a pattern formed by the particles concentrated in the water droplets remaining on the surface when the water vaporizes at the final stage of drying, which seriously affects the device yield. In particular, the surface of the substrate after etching is very activated, and when the surface of silicon is dried with pure water and oxygen mixed, a natural oxide film (S
Although iO ₂ ) is formed, particles in the atmosphere are taken into the film, which also contributes to the above-mentioned watermark.

[0004]

Conventionally, in the drying step, it has been practiced to blow an inert gas such as nitrogen gas onto the surface of the substrate through a nozzle. However, in the method using this nozzle, the entire surface of the substrate is covered. Cannot be covered with an inert gas,
On the silicon substrate, there is a problem that the formation of a natural oxide film is inevitable locally. Further, since the inert gas supplied from the nozzle has a relatively high pressure and is vigorously ejected, turbulence of the air flow is formed around the substrate, and the particles existing around the substrate are agitated. However, there is a problem in that the probability of particles adhering to the substrate surface increases. Further, since the inert gas has a relatively high pressure, there is a disadvantage that the amount of gas ejected from the nozzle becomes large, and there is a problem in terms of running cost.

On the other hand, paying attention to the apparatus for spin drying, many chuck mechanisms for holding a substrate have plane portions such as chuck claws and a plurality of arms radially extending from a rotation axis. Since the above member is used, there is a problem of particle scattering due to turbulence of the air flow due to high speed rotation.

The present invention has been made in view of the above circumstances, and the entire surface of the substrate to be processed can be surrounded by an atmosphere of an inert gas such as nitrogen gas, and the turbulence of the air flow around the substrate can be prevented. An object of the present invention is to provide a substrate processing apparatus that can reduce the supply amount of an inert gas without being formed.

[0007]

In order to solve the above-mentioned problems, the present invention provides a substrate holding unit for holding and rotating a substrate, and a treatment liquid on the surface to be treated of the substrate held by the substrate holding unit. A first processing liquid supply unit for supplying, an inert gas supply unit installed above the substrate holding unit for forming a downflow of an inert gas so as to cover the entire surface of the substrate to be processed, and the substrate holding unit. And a housing for accommodating the first processing liquid supply part and the inert gas supply part.

According to the present invention, the down flow of the inert gas is formed by the inert gas supply portion so as to cover the entire surface of the substrate to be processed, so that the entire surface of the substrate to be processed is filled with the inert gas. It can be surrounded by an atmosphere, and it is possible to prevent the surface to be processed of the substrate from being deteriorated due to the presence of oxygen or the like during various kinds of processing. In addition, since the downflow of the inert gas is a vertical laminar flow, turbulence of the airflow is not formed around the substrate, and the probability that particles adhere to the substrate surface can be reduced. Furthermore, since the volume of the processing space for the substrate formed in the housing can be reduced, the supply amount of the inert gas can be reduced.

One aspect of the present invention is characterized by comprising a closing body which opens and closes an opening formed in a housing for loading and unloading a substrate. With this, after the substrate is loaded into the housing by the robot hand or the like,
The opening of the housing can be closed by a closing body to form a closed space. In one aspect of the present invention, a second processing liquid supply unit that supplies the processing liquid to the back surface of the substrate held by the substrate holding unit is provided. As a result, both the surface to be processed and the back surface of the substrate can be processed at the same time. Further, different processing liquids can be supplied to the surface to be processed and the back surface of the substrate, and a rinse liquid such as pure water is supplied to the back surface during the etching process so that the processing liquid on the surface to be processed is transferred to the back surface. It can prevent turning. One aspect of the present invention is characterized in that an inert gas supply unit is provided below the substrate holding unit and supplies an inert gas to the back surface side of the substrate. With this, even if the substrate holder rotates at a high speed during processing, it is possible to prevent the inert gas from being supplied to the back surface of the substrate to cause the back surface of the substrate to have a negative pressure.

In one aspect of the present invention, the inert gas supply section includes a filter for capturing fine particles in the inert gas, and an upper space above the filter for supplying the inert gas to the filter. It is characterized by that. One aspect of the present invention is characterized in that a processing space that surrounds the periphery of the substrate during processing is formed by the filter, the closing body, and the substrate holding portion. As a result, a processing space having a small volume can be formed around the substrate, so that a small amount of inert gas needs to be supplied to the processing space. In one aspect of the present invention, the substrate holding unit includes a disc-shaped rotating wheel and a plurality of substrate holding units for holding a substrate that is installed on an outer peripheral portion of the rotating wheel and is movable in a radial direction of the rotating wheel by a predetermined distance. And a plurality of temporary placement pins for temporarily placing the substrate on the rotating wheel. By adopting a moving mechanism for moving the substrate holding pin and the temporary placement pin by fluid pressure such as air pressure, the moving mechanism can be made a simple structure.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION An embodiment of a substrate processing apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 is a schematic sectional view of a substrate processing apparatus according to this embodiment. As shown in FIG. 1, the substrate processing apparatus includes a substrate holding unit 1 for horizontally holding a substrate W such as a semiconductor wafer, and nitrogen gas (N ₂ ) or the like over the entire surface to be processed (upper surface) of the substrate W. Of the inert gas supply unit 2 for forming the down flow of the inert gas of the substrate W
A first processing liquid supply unit 3 for supplying the processing liquid to the surface to be processed (upper surface) of the substrate, and a second processing liquid for supplying the processing liquid to the back surface (lower surface) of the substrate
The processing liquid supply unit 4 and the substrate holding unit 1, the inert gas supply unit 2, the first processing liquid supply unit 3, and the second processing liquid supply unit 4 are housed in a cylindrical container-shaped housing 5. .

The housing 5 has a closed lower portion, which is not shown in the drawing, but is formed into a closed cylindrical container.
It is provided with a carry-in / out port 5a for carrying in / out the substrate W, a gas supply port 5b for supplying an inert gas such as nitrogen gas into the housing, and a gas discharge port 5c for discharging the inert gas from the inside of the housing to the outside. . The carry-in / out port 5a is opened and closed by an annular closing body 6 which moves up and down by an elevating mechanism (not shown) such as an air cylinder. That is, the closing body 6
When loading and unloading the substrate W, it lowers downward to open the loading / unloading port 5a, and when processing the substrate W, rises to close the loading / unloading port 5a and form a sealed space in the housing 5. The gas supply port 5b is connected to an inert gas supply source 20 that stores an inert gas such as nitrogen gas having a predetermined pressure, and an annular header 5d is formed inside the gas supply port 5b. As a result, the inert gas supplied from the inert gas supply source 20 to the gas supply port 5b is supplied to the inert gas supply unit 2 through the plurality of openings 5e formed in the upper portion of the header 5d. ing.

A partition wall 7 is formed at an intermediate portion between the carry-in / out port 5a and the gas discharge port 5c in the housing 5, and the partition wall 7 partitions the interior of the housing 5 into an upper chamber 8 and a lower chamber 9. Has been. Then, the upper chamber 8 can form a closed space that is isolated from the external space 10 by the housing 5, the closing body 6, and the partition wall 7. When the substrate processing apparatus is installed in a clean room, the external space 10 is a space where a downflow of clean air is formed.
The lower chamber 9 is also connected to an exhaust duct of a semiconductor device manufacturing facility via a duct (not shown) connected to the gas exhaust port 5c.

Further, at the bottom of the upper chamber 8, there is installed a discharge portion 11 having a discharge pipe 11a for discharging the processing liquid and the inert gas from the inside of the upper chamber 8. Then, the inert gas discharged from the upper chamber 8 through the discharge pipe 11a of the discharge unit 11 passes through the gas discharge port 5c and is discharged to the outside. Further, the processing liquid discharged from the upper chamber 8 via the discharge pipe 11a of the discharge part 11 is a drainage processing device (not shown) installed outside the housing 5.
Sent to.

On the other hand, the inert gas supply unit 2 for forming a downflow of an inert gas such as nitrogen gas in the upper chamber 8 has a top space 13 located above the upper surface of the header 5d and a top space 13. It is composed of a ULPA filter 14 installed inside. ULPA filter 14
Is an air filter mainly used in a clean room for manufacturing ULSI and the like, and has a particle size of 0.
Fine particles of 15 μm can be collected by 99.9995% or more, and the initial pressure loss is 300 Pa or less. The ULPA filter 14 has an outer diameter slightly larger than the diameter of the substrate W, and is capable of forming a vertical laminar flow of an inert gas over the entire surface to be processed (upper surface) of the substrate W. Note that the filter may be a HEPA filter instead of the ULPA filter, as long as it can capture fine particles mixed in the inert gas.

The inner diameters of the header 5d and the closing body 6 are
Since it is set to a value slightly larger than the outer diameter of the substrate W,
In the upper chamber 8, a processing space 8a having a small volume is formed around the substrate W which is the object to be processed by the ULPA filter 14, the header 5d and the inner peripheral wall of the closing body 6, and the rotating wheel 16 (described later). It is supposed to be done.
Thus, since the volume of the processing space 8a is small, the volume of the inert gas supplied to the processing space 8a is small. Then, in the processing space 8a, a flow velocity similar to the downflow in the clean room (for example, 0.2 to 0.3 m /
The downflow is formed by a vertical laminar flow of an inert gas having s). As described above, since the laminar flow is formed in the processing space 8a, the particles are not rolled up and do not stay, and even if a few particles are present in the processing space 8a, It can be discharged to the outside from the inside of the processing space 8a and the upper chamber 8 along with the flow.

The substrate holding part 1 for holding the substrate W has a disk-shaped rotating wheel 16 and a plurality of substrate fixing pins 17 for holding (chucking) the substrate W, which are installed on the outer peripheral part of the rotating wheel 16. A plurality of temporary placement pins 18 for temporarily placing the substrate W are provided on the outer periphery of the rotating wheel 16. The rotary wheel 16 has a hollow shaft portion 16a extending downward, and the shaft portion 16a is supported by a support portion 7a formed at the center of the partition wall 7 via a bearing 19. The shaft portion 16a of the rotating wheel 16 is connected to a motor (not shown), and the rotating wheel 1
6 is a predetermined rotation speed (for example, 500 to 3000 rpm)
It rotates at (min ^-1 )). Further, in the rotary wheel 16 and the shaft portion 16a, an air path 21 for supplying compressed air for pressing the substrate fixing pin 17 outward in the radial direction, and a compression for pressing the temporary placement pin 18 upward. An air path 22 for supplying air is formed. When the compressed air is not supplied to the air path 21, the substrate fixing pin 17 is engaged with the outer peripheral edge of the substrate W to hold (chuck) the substrate W, and the compressed air is supplied to the air path 21, The board fixing pin 17 has a small distance (for example, 1 to 2 m) outward in the radial direction of the rotating wheel 16.
(about m) to move and release the chuck of the substrate W. Further, when the compressed air is not supplied to the air path 22, the temporary placement pin 18 descends and is separated from the substrate W, and when the compressed air is supplied to the air path 22, the temporary placement pin 18 rises and the substrate W. The lower surface of the can be supported.

2 to 6 are views showing a detailed structure for holding the substrate W by the substrate holding part 1. As shown in FIG. Figure 2 is II of Figure 1
1. FIG. 3 is a detailed view of the III section of FIG. 1, FIG. 4 is a detailed view of the IV section of FIG. 1, and FIGS. 5 and 6 are detailed views of the V section of FIG. Figure 2
As shown in FIG. 3, three substrate fixing pins 17 are installed on the circumference of a predetermined diameter, and can engage the outer peripheral edge of the substrate W to chuck the substrate W. Two
It is configured so that the substrate W can be opened by moving radially outward from the state shown in (1) to be separated from the outer peripheral edge of the substrate W by a small distance. Three temporary placement pins 18 are provided on the circumference of a predetermined diameter, and the temporary placement of the substrate W is possible by contacting the back surface of the outer peripheral portion of the substrate W. The substrate W is temporarily placed on the temporary placing pin 18 before the substrate W is chucked by the substrate fixing pin 17, and when the substrate fixing pin 17 moves radially outward. 1
This is when the chuck of the substrate W by 7 is released. The surface on which the substrate W is held by the substrate fixing pin 17 and the surface on which the substrate W is temporarily placed by the temporary placement pin 18 are set on the same surface.

Next, the lifting mechanism for the temporary placement pin 18 is shown in FIG.
Will be described with reference to. As shown in FIG. 3, the lower portion of the temporary placement pin 18 serves as a vertically movable piston portion 18a that is mounted in a vertical fitting hole 25 formed in the rotary wheel 16. It communicates with the air passage 22. The piston portion 18a is biased downward by the compression coil spring 26. Therefore, the air path 22
When compressed air is supplied to the
8a, that is, the temporary placement pin 18 moves up, and the air path 2
When the supply of compressed air to 2 is stopped, the urging force of the compression coil spring 26 lowers the piston portion 18a, that is, the temporary placement pin 18.

Next, the horizontal movement mechanism of the board fixing pin 17 will be described with reference to FIG. As shown in FIG. 4, a piston 28 that is movable in the radial direction of the rotary wheel 16 is mounted in a lateral fitting hole 27 formed in the rotary wheel 16. The fitting hole 27 communicates with the air passage 21. A compression coil spring 29 is arranged on the opposite side of the piston 28 with the board fixing pin 17 interposed therebetween, and the board fixing pin 17 is urged inward in the radial direction of the rotary wheel 16 by the compression coil spring 29. Has been done. Therefore, when compressed air is supplied to the air passage 21, the piston 28 is moved radially outward by the air pressure to press the substrate fixing pin 17, and the substrate fixing pin 17 is slightly outward in the radial direction. (Gap g in FIG. 4)
Just move. Then, when the supply of the compressed air to the air path 21 is stopped, the biasing force of the compression coil spring 29 causes the board fixing pin 17 to move inward in the radial direction,
Return to the position shown in FIG.

Next, an air supply mechanism for supplying compressed air to the air passage 22 will be described with reference to FIGS. 5 and 6. FIG. 5 shows a state when the air supply mechanism is operating and is supplying compressed air to the air path 22, and FIG. 6 is a state when the air supply mechanism is not operating and is not supplying compressed air to the air path 22. Indicates the status. As shown in FIG. 5, a fitting hole 31 is formed in the support portion 7 a, and a piston rod 33 connected to an air cylinder 32 is mounted in the fitting hole 31. When the rotary wheel 16 is stopped, the air cylinder 32 operates, the piston rod 33 moves forward, and the tip of the piston rod 33 engages with the shaft portion 16a of the rotary wheel 16. An air passage 34 is formed inside the piston rod 33, and when the tip of the piston rod 33 engages with the shaft portion 16a, the air passage 36 formed in the support portion 7a communicates with the air passage 34. As a result, the compressed air E is supplied to the air passage 22, and the temporary placement pin 18 rises as described above.

On the other hand, when the operation of the air cylinder 32 is released, as shown in FIG. 6, the piston rod 33 retracts, the tip of the piston rod 33 separates from the shaft portion 16a, and compressed air to the air passage 22 is released. Is stopped, and the temporary placement pin 18 descends. At this time, the air path 34
And the air path 36 are not in communication with each other. The shaft portion 16
A gasket 37 for sealing is provided at the end of the air passage 22 formed in a. In the state shown in FIG. 6, the rotary wheel 16 becomes rotatable. Air path 21
The air supply mechanism for supplying compressed air to
Since it is the same as the air supply mechanism shown in FIG.

Next, the first processing liquid supply unit 3 for supplying the processing liquid to the surface to be processed (upper surface) of the substrate W will be described with reference to FIGS. 7 and 8. FIG. 7 is a plan view of the first processing liquid supply unit 3, and FIG. 8 is a side view of the first processing liquid supply unit 3. As shown in FIGS. 7 and 8, the first processing liquid supply unit 3 has a processing liquid supply passage 40a inside and a rack 4 on the side surface.
0b-formed rod-shaped nozzle body 40 and rack 40b
And a pinion 41 that meshes with. Nozzle body 4
A processing liquid supply pipe 42 is connected to the rear end of 0, and the processing liquid supply pipe 42 is connected to the supply passage 40a in the nozzle body 40 and to the processing liquid supply source 43. A nozzle 40s that communicates with the supply path 40a and opens downward is formed at the tip of the nozzle body 40.

The nozzle body 40 can be moved forward and backward by a rack 40b and a pinion 41, and when the nozzle body 40 advances, the nozzle 40s is positioned above the center O of the substrate W. The nozzle 4
0s is located immediately above the substrate W, as shown in FIG. The nozzle body 40 is moved by the rack 40b and the pinion 41 to above the substrate W only when the processing liquid is supplied, and the nozzle 40s can be stopped at an arbitrary position in the radial direction above the substrate W. . And the nozzle body 4
When 0 is most retracted, the nozzle 40s is located radially outward of the outer peripheral edge of the substrate W. The housing 5 is formed with an opening 5f through which the nozzle body 40 is inserted, and the opening 5f and the outer peripheral surface of the nozzle body 40 are sealed with a gasket (not shown) or the like.

In the above structure, the processing liquid B can be supplied to the predetermined position in the radial direction of the surface to be processed of the substrate W by moving the nozzle body 40 forward and backward. The nozzle body 40 may be moved forward and backward while supplying the processing liquid to the substrate W from the nozzle 4s. As the treatment liquid supplied from the nozzle 40s, an etching liquid such as hydrofluoric acid, hydrochloric acid, sulfuric acid, hydrogen peroxide solution or a mixed solution thereof is used in the etching step, and ammonia and hydrogen peroxide solution are used in the cleaning step. A cleaning solution such as a mixed solution or hydrofluoric acid is used, and a rinse solution such as pure water, electrolyzed water, or dissolved gas water is used in the rinse step after cleaning. In addition, a plurality of nozzles for supplying the processing liquid to the surface to be processed and the back surface of the substrate may be provided on both the surface to be processed and the back surface, and different nozzles may be used for each type of the processing liquid.

Next, the second processing liquid supply unit 4 for supplying the processing liquid to the back surface (lower surface) of the substrate W will be described with reference to FIG.
As shown in FIG. 1, the second processing liquid supply unit 4 is a hollow shaft body 4 installed in the hollow portion of the shaft portion 16 a of the rotary wheel 16.
It is composed of 5. Shaft part 16a of the rotating wheel 16
A bearing 47 is installed between the hollow shaft body 45 and
While the hollow shaft body 45 is fixed (non-rotating), the rotating wheel 16 and the shaft portion 16a are rotatable.
In the hollow shaft body 45, a supply passage 45a for the processing liquids C and D,
A supply path 45b for an inert gas A such as nitrogen gas is formed. The upper end of the supply path 45a constitutes a nozzle 45s that opens upward. The upper end portion of the hollow shaft body 45 is a conical portion 45c.
As a result, the processing liquid supplied to the back surface of the substrate W from the nozzle 45s at the tip of the supply path 45a and then falling is smoothly guided toward the rotary wheel 16. The supply path 45a is connected to the processing liquid supply source 43 or another processing liquid supply source. On the other hand, the supply passage 45b opens laterally near the lower end of the conical portion 45c, and the supply passage 45b supplies the inert gas A to the space between the back surface of the substrate W and the rotating wheel 16. It has become so.
The supply passage 45b is connected to the inert gas supply source 20.

Next, the operation when various processes such as etching process, cleaning process, rinsing process and drying process are performed by the substrate processing apparatus configured as shown in FIGS. 1 to 8 will be described. First, the closing body 6 is lowered to bring in / out the entrance 5a.
Open up. In this state, a robot hand (not shown) holding the substrate W passes through the carry-in / out port 5a and enters the housing 5. At this time, the air supply mechanism that supplies the compressed air to the air path 22 operates, and the piston rod 33
5 engages with the shaft portion 16a of the rotary wheel 16 to enter the state shown in FIG. 5, compressed air is supplied to the air passage 22, and the temporary placement pin 18 is raised. Further, the air supply mechanism that supplies the compressed air to the air passage 21 also operates, and the tip of the piston rod 33 causes the shaft portion 16 a of the rotating wheel 16 to move.
, The compressed air is supplied to the air passage 21, the piston 28 presses the substrate fixing pin 17, and the substrate fixing pin 17 is in a state of moving radially outward.

In this state, the substrate W is transferred from the robot hand onto the temporary placement pin 18. Then, the robot hand exits from the carry-in / out port 5a. Next, the closing body 6 rises to close the carry-in / out port 5a. After closing the carry-in / out port 5a, the inert gas is supplied from the inert gas supply source 20 to the top space 13 via the gas supply port 5b and the header 5d. The inert gas in the top space 13 is ULPA.
After passing through the filter 14, it becomes extremely clean,
It gently flows downward from the lower surface of the ULPA filter 14. As a result, a downflow of the inert gas is formed in the processing space 8a, and as a result, a vertical laminar downflow of the inert gas is formed so as to cover the entire surface of the substrate W to be processed. At the same time, the supply path 45b of the hollow shaft body 45
The inert gas A may be supplied also to the space between the back surface of the substrate W and the rotating wheel 16 via.

On the other hand, as described above, in the state where the substrate W is temporarily placed on the temporary placement pin 18, the air supply mechanism for supplying the compressed air to the air passage 21 is deactivated and the piston rod 33 is retracted. Then, when the tip of the piston rod 33 separates from the shaft portion 16a and the supply of compressed air to the air passage 21 is stopped, the board fixing pin 17 is moved radially inward by the urging force of the compression coil spring 29. The substrate W is moved and chucked. Then, the air supply mechanism that supplies the compressed air to the air path 22 is deactivated, the piston rod 33 is retracted, and the tip of the piston rod 33 is moved to the shaft portion 1.
When it is separated from 6a and the supply of compressed air to the air path 22 is stopped, the temporary placement pin 18 is lowered by the urging force of the compression coil spring 26. Through the above operations, the rotary wheel 16 becomes rotatable.

Next, a motor (not shown) is driven to rotate the rotary wheel 16 chucking the substrate W at a predetermined speed. After the substrate W is rotated, the processing liquid is supplied from the nozzle 40s in the first processing liquid supply unit 3 to the surface to be processed (upper surface) of the substrate W, and the substrate is supplied from the nozzle 45s of the hollow shaft body 45 in the second processing liquid supply unit 4. The processing liquid is supplied to the back surface (lower surface) of W. During this processing step, the rotary wheel 16 continues to rotate at a predetermined rotational speed, for example 500-1000 rpm. In this state, if the processing liquid is an etching liquid,
The surface to be processed of the substrate W can be etched. When the etching process is performed only on the surface to be processed of the substrate W, the etching liquid may be supplied to the surface to be processed of the substrate W only from the nozzle 40s of the first processing liquid supply unit 3. And
In order to prevent the etching liquid from flowing to the back surface of the substrate W, pure water or the like may be supplied from the nozzle 45s of the second processing liquid supply unit 4.

On the other hand, when cleaning the substrate W,
The nozzle 40s of the first processing liquid supply unit 3 supplies a cleaning liquid such as a chemical liquid to the surface to be processed of the substrate W, and the nozzle 45s of the second processing liquid supply unit 4 supplies a cleaning liquid such as a chemical liquid to the back surface of the substrate W. . Further, in the rinse step after the cleaning step, the rinse liquid such as pure water is supplied to the surface to be processed of the substrate W from the nozzle 40s of the first processing liquid supply unit 3 and the nozzle 45s of the second processing liquid supply unit 4 is supplied. A rinse liquid such as pure water is supplied to the back surface of the substrate W from. After the rinse step, the step of drying the substrate W is performed. In this drying process, the supply of the rinse liquid from the nozzle that has been supplied in the rinse process is stopped, and the rotation speed of the rotary wheel 16 is rotated at a high speed, for example, 1500 to 500.
The substrate W is spin dried at 2500 rpm. After the spin drying, the closing body 6 is lowered, the loading / unloading port 5a is opened, and the processed substrate W is unloaded by the robot hand. By repeating the above steps, a large number of substrates W can be processed one by one. In FIG. 1, the inert gas discharged from the housing is A ', the treatment liquid after use is B',
It is represented by C'and D '.

In the present embodiment, after the carry-in / out port 5a is closed by the closing body 6, the inert gas is supplied from the inert gas supply unit 2 to the upper chamber 8,
That is, the air in the processing space 8a is gradually replaced with the inert gas. Then, during the various steps described above, the replacement of air with the inert gas has already been completed, and the inert gas is down so as to cover the entire surface of the substrate W from the inert gas supply unit 2. Since the flow is formed, the entire surface of the substrate W to be processed is covered with the inert gas atmosphere. Since oxygen does not exist around the substrate W, the substrate W
Even if is a silicon substrate, a natural oxide film (SiO ₂ ) is not formed on the silicon substrate. Further, the inert gas is also supplied from the supply passage 45b of the hollow shaft body 45 to the back surface side of the substrate W, and the back surface side of the substrate W becomes negative due to the high speed rotation of the substrate W and the rotating wheel 16. Although there is a risk of a negative pressure, the supply of the inert gas from the supply passage 45b prevents the rear surface of the substrate W from having a negative pressure. Further, in the upper chamber 8, the processing space 8a having a small volume is formed around the substrate W by the ULPA filter 14, the inner peripheral wall of the header 5d and the closing body 6, and the rotating wheel 16, so that the processing space 8a is formed. A small amount of inert gas may be supplied to the.

Further, in this embodiment, all the rotating bodies such as the rotating wheel 16, the substrate fixing pin 17, and the temporary placing pin 18 in the substrate holding unit 1 which holds the substrate W and rotates at a high speed are disc-shaped. Or, since it is formed in a cylindrical shape and no member having a flat surface is used,
The turbulence of the air flow due to the high speed rotation of the rotating body can be minimized, and the scattering of particles can be minimized.

[0034]

As described above, according to the present invention,
By forming the down flow of the inert gas so as to cover the entire surface of the substrate to be processed by the inert gas supply unit, the entire surface of the substrate to be processed can be surrounded by the atmosphere of the inert gas, and various treatments can be performed. It does not deteriorate the surface to be processed of the substrate. In addition, since the downflow of the inert gas is a vertical laminar flow, turbulence of the airflow is not formed around the substrate, and the probability that particles adhere to the substrate surface can be reduced. Furthermore, since the volume of the processing space for the substrate formed in the housing can be reduced, the supply amount of the inert gas can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic cross-sectional view of a substrate processing apparatus according to this embodiment.

FIG. 2 is a view on arrow II in FIG.

FIG. 3 is a detailed view of a part III in FIG.

FIG. 4 is a detailed view of an IV section in FIG.

FIG. 5 is a detailed view of a V portion of FIG.

FIG. 6 is a detailed view of a V portion of FIG.

FIG. 7 is a plan view of a first processing liquid supply unit.

FIG. 8 is a side view of a first processing liquid supply unit.

[Explanation of symbols]

1 Substrate holder 2 Inert gas supply section 3 First processing liquid supply unit 4 Second processing liquid supply unit 5 housing 5a entrance / exit 5b Gas supply port 5c gas outlet 5d header 5f opening 6 occluder 7 partition walls 7a support 8 Upper chamber 8a processing space 9 Lower chamber 10 external space 11 Discharge part 11a discharge pipe 13 Top space 14 ULPA filter 16 rotating wheels 16a shaft 17 Board fixing pin 17a support part 18 Temporary storage pin 18a Piston part 19,47 bearings 20 Inert gas supply source 21,22,34,36 Air path 25, 27, 31 Fitting holes 26,29 Compression coil spring 28 pistons 32 air cylinder 33 Piston rod 37 Gasket 40 nozzle body 40a supply path 40b rack 40s, 45s nozzle 41 pinion 42 Processing liquid supply pipe 43 Treatment liquid supply source 45 hollow shaft 45a, 45b supply path 45c conical part 46 hollow shaft g gap A inert gas B, C, D treatment liquid W board

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) G02F 1/1333 500 H01L 21/306 J (72) Inventor Toshio Yokoyama 11-1 Haneda Asahi-cho, Ota-ku, Tokyo No. F-term in EBARA CORPORATION (reference) 2H088 FA21 FA30 HA01 MA20 2H090 JB02 JC19 3B201 AA01 AB02 AB33 AB47 BB42 BB92 BB99 CD11 CD22 CD34 5F043 EE03 EE08 EE27 GG10

Claims (7)

[Claims] 1. A substrate holding part for holding and rotating a substrate, a first processing liquid supply part for supplying a processing liquid to a surface to be processed of the substrate held by the substrate holding part, and an upper part of the substrate holding part. And an inert gas supply unit that forms a downflow of an inert gas so as to cover the entire surface of the substrate to be processed, the substrate holding unit, the first processing liquid supply unit, and the inert gas supply unit. A substrate processing apparatus, comprising: 2. The substrate processing apparatus according to claim 1, further comprising a closing body that opens and closes an opening formed in a housing for loading and unloading the substrate. 3. The substrate processing apparatus according to claim 1, further comprising a second processing liquid supply unit that supplies a processing liquid to the back surface of the substrate held by the substrate holding unit. 4. The inert gas supply unit, which is installed below the substrate holding unit and supplies an inert gas to the back side of the substrate, according to any one of claims 1 to 3. The substrate processing apparatus described. 5. The inert gas supply unit includes a filter for capturing fine particles in the inert gas, and an upper space above the filter for supplying the inert gas to the filter. The substrate processing apparatus according to any one of claims 1 to 4. 6. The substrate processing apparatus according to claim 5, wherein the filter, the closing body, and the substrate holding unit form a processing space that surrounds the periphery of the substrate during processing. 7. The substrate holding unit includes a disc-shaped rotating wheel, and a plurality of substrate holding pins for holding a substrate which is installed on an outer peripheral portion of the rotating wheel and is movable by a predetermined distance in a radial direction of the rotating wheel. 7. The substrate processing apparatus according to claim 1, further comprising a plurality of temporary placement pins installed on the rotating wheel for temporarily placing a substrate.