JPH11195696A - Substrate holder and substrate treatment device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wafer holder made of silicon wafer with tooled. SOLUTION: A wafer holder 31 is made of a silicon wafer by means of the lithography technology. The wafer holder 31 having seals 31a, 31b and a suction hole 31c sucks a wafer to be held by depressurizing between the seals 31a and 31b. Only the seals 31a and 31b, and the suction hole 31c are brought into contact with the wafer to be held.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate support and a substrate processing apparatus, and more particularly, to a substrate support made of a silicon material, a substrate processing apparatus including the substrate support, a method of manufacturing and handling the substrate support. The present invention relates to a method and a substrate processing method.

[0002]

As a device for supporting a substrate to be processed in a semiconductor device manufacturing process, there is a substrate supporting device for supporting a substrate by vacuum suction. As a substrate supporting table which forms a part of such a substrate supporting apparatus, a substrate provided with a suction groove on a plate made of a highly rigid metal or ceramic material is usually used.

However, conventional substrate supports are generally expensive, and it is desired to provide a less expensive substrate support.

[0004]

The substrate support according to the present invention is characterized by being made of a silicon material.

[0005] Further, the substrate support according to the present invention is characterized by processing a silicon wafer.

[0006] It is preferable that the above-mentioned substrate support base has a suction portion for sucking a substrate to be supported.

In the above-mentioned substrate support, it is preferable that the suction portion is formed by a lithography technique.

[0008] In the above-described substrate support table, it is preferable that the suction section is formed by etching a silicon wafer.

[0009] In the above-mentioned substrate support table, it is preferable that the suction portion is formed by wet etching a silicon wafer.

[0010] In the above-described substrate support table, the suction section may include a sealing section for vacuum-sucking the substrate and a suction hole for discharging gas in a space surrounded by the sealing section. preferable.

[0011] In the above-mentioned substrate support, the sealing portion is provided doubly along the outer periphery of the substrate to be supported, and the suction hole is provided in the double sealing portion. Preferably, it communicates with the inside.

[0012] In the above-mentioned substrate support table, it is preferable that the sealing portion protrudes like a dike with respect to the periphery thereof.

In the above-mentioned substrate support, it is preferable that only the sealing portion comes into contact with the substrate when the substrate is sucked.

It is preferable that the above-mentioned substrate supporting base further has a bending preventing portion for preventing the substrate from bending when the substrate is sucked.

In the above-described substrate support, it is preferable that the deflection preventing portion is disposed at a position sandwiched by the sealing portion.

In the above-mentioned substrate support, it is preferable that only the sealing portion and the deflection preventing portion come into contact with the substrate when the substrate is sucked.

In the above-described substrate support, it is preferable that respective surfaces of the sealing portion and the deflection preventing portion that come into contact with the substrate to be supported are substantially in the same plane.

In the above-described substrate support table, it is preferable that the suction section is disposed at a position where the suction section can be suctioned around a peripheral portion of the substrate to be supported.

It is preferable that the substrate support is provided with a pin hole through which a load pin for lifting and lowering the substrate to be supported on the substrate support is passed through the main body.

The above silicon wafer is, for example, SEM
It is preferable that the silicon wafer conforms to the I standard, the JAIDA standard, and other standards.

A substrate processing apparatus according to the present invention is a substrate processing apparatus in which two substrates are superimposed and brought into close contact with each other, wherein an attaching / detaching mechanism for attaching / detaching the above-mentioned substrate supporting table and the mounted substrate supporting table are provided. Pressure means for pressing the second substrate toward the first substrate in a state where the second substrate is opposed to the first substrate supported by the first substrate.

In the above-described substrate processing apparatus, it is preferable that the pressurizing unit presses a substantially central portion of the second substrate.

The above-mentioned substrate processing apparatus further includes substrate operating means for releasing the support of the second substrate after supporting the second substrate to face the first substrate supported by the substrate support. It is preferable that the pressing unit presses the second substrate in accordance with the release of the support of the second substrate by the substrate operating unit.

In the above-described substrate processing apparatus, the substrate support supports the first substrate substantially horizontally, and the substrate operating means supports the second substrate substantially horizontally above the first substrate. It is preferable that the support of the second substrate is released after the above.

The above-described substrate support and substrate processing apparatus are suitable for manufacturing, for example, an SOI substrate.

A cleaning method according to the present invention is characterized in that the above-mentioned substrate support is housed in a wafer cassette for housing a wafer for manufacturing a semiconductor device and is cleaned.

In a method of handling a substrate processing apparatus according to the present invention, a step of removing the substrate support from the substrate processing apparatus, and a step of mounting the removed substrate support on a wafer for accommodating a wafer for manufacturing a semiconductor device. The method includes a step of storing the substrate supporting table in a cassette for cleaning, and a step of mounting the substrate supporting table having been cleaned on the substrate processing apparatus.

The method of manufacturing a substrate support according to the present invention is a method of manufacturing a substrate support, which comprises forming a SiO ₂ film so as to cover the entire silicon wafer, and forming an S ₂ film on one surface.
forming a first photoresist film on the iO ₂ film;
And patterning the first photoresist film, exposing the step of exposing the SiO ₂ film in a portion to be formed a seal for vacuum suction, a silicon wafer by etching the SiO ₂ film to expose portions Removing the remaining first photoresist film, etching the exposed portion of the silicon wafer to a predetermined depth, forming an SiO ₂ film so as to cover the entire silicon wafer, Forming a second photoresist film on the other surface of the SiO ₂ film, and patterning the second photoresist film to form a portion of the SiO ₂ film where a suction hole for vacuum suction is to be formed;
Exposing the film, etching the exposed portion of the SiO ₂ film to expose the silicon wafer, removing the remaining second photoresist mask, etching the exposed portion of the silicon wafer The method includes a step of forming a suction hole penetrating the silicon wafer and a step of removing the remaining SiO ₂ film.

[0029]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a plan view showing the structure of a wafer (substrate) support 31 according to a preferred embodiment of the present invention.

The wafer support 31 is made of a commercially available silicon wafer, for example, SEMI standard, JAID
It can be manufactured by processing a silicon wafer for manufacturing a semiconductor device of A standard or the like. Since a wafer for manufacturing a semiconductor device has a high surface flatness, it is used as a suction surface for suctioning a wafer to support the surface.
A highly accurate wafer support can be easily manufactured. Therefore, for example, a wafer support table excellent in mass productivity and cost can be obtained.

For processing the silicon wafer, for example, a general lithography technique can be employed. According to this lithography technique, for example, a pattern can be formed with an accuracy of a submicron unit, and therefore, it is extremely useful for manufacturing the wafer support according to this embodiment.

The wafer support table 31 has double embankment-shaped sealing portions 31a and 31b and a suction port 31d, and is formed by the double sealing portions 31 and 31b and a wafer to be supported to be suctioned. The gas in the space to be exhausted is discharged through the suction port 31d, so that the wafer can be sucked.

The wafer support table 31 has a pin-shaped flexure for preventing the adsorbed wafer from flexing when the space between the double sealing portions 31a and 31b is decompressed. A large number of prevention parts 31c are formed between the sealing parts 31a and 31b. In this embodiment, the deflection preventing portion 31c is provided only between the sealing portions 31a and 31b, but it can also be provided at the center.

Sealing portions 31a and 31b and deflection preventing portion 31c
The surfaces of the silicon wafers, which are the materials of the wafer support table 31, are used as they are as the surfaces in contact with the suction targets.

Further, the wafer support table 31 is provided with a pin hole 31e for passing a load pin (described later) for attaching and detaching a wafer to be suctioned.

FIG. 2 is a sectional view of a part of the wafer support table 31 shown in FIG. The height h of the sealing portions 31a and 31b and the deflection preventing portion 31c is preferably, for example, about 50 μm.
In addition, it is preferable that the widths d4 and d1 of the sealing portions 31a and 31b be reduced to some extent from the viewpoint of preventing particles from being caught between the wafers to be sucked.
For example, about 0.2 mm is preferable. Further, the diameter of the deflection preventing portion 31c is preferably reduced to some extent from the same viewpoint, and for example, is preferably about 0.2 mm.

FIG. 3 is a sectional view showing the structure of the wafer support device 3 including the wafer support table 31 shown in FIG. The wafer support device 3 is configured by vacuum-adsorbing the wafer support table 31 on the base 32.

The base 32 has an annular groove 32a for vacuum-sucking the wafer support table 31 and a suction hole 32b for sucking gas in the groove 32a. The wafer support table 31 is sucked. The suction hole 32b is provided in the pipe 18 provided with the valve 19a in the middle.
It is connected to the vacuum pump 20 via a.

The base 32 is provided with a suction hole 31d communicating with the lower part of the wafer support table 31 so that the valve 19b
Is provided with a suction hole 32c for connecting to the vacuum pump 20 via a pipe 18b provided with a hole.

When the wafer support 31 is mounted on the base 32, the valve 19a is opened, and when the wafer 1 to be processed is mounted on the wafer support 31, the valve 19b is opened.

Further, the base 32 has a pin hole 32d through which load pins for attaching and detaching the wafer 1 to and from the wafer support table 31 pass.

The wafer support table 31 is used to remove particles that may adhere to the suction surface of the wafer 1.
It is preferable to wash regularly. As described above, when a silicon wafer for manufacturing a semiconductor device is processed to manufacture the wafer support table 31, a commercially available wafer carrier can be directly used for this cleaning. That is, in this case, the wafer support 3 is placed on a commercially available wafer carrier.
1 can be stored and cleaned using a general wafer cleaning apparatus.

Next, an example of a manufacturing process of the wafer support table 31 will be described. 4A to 4N are views showing a process of manufacturing the wafer support 31 by applying a general lithography technique.

First, an Si wafer 2 for manufacturing a semiconductor device
01, and as shown in FIG.
1a, on the front, back and side walls, a Si wafer 2
A film 202a for forming a mask pattern when etching 01a is formed. As a material of the film 202a, for example, SiO ₂ by thermal oxidation or the like and Si ₃ N ₄ by a CVD method or the like are preferable.

Next, as shown in FIG. 4B, a photoresist film 203a is formed on the wafer shown in FIG. 4A.

Next, the photoresist film 203a is irradiated with ultraviolet light through a photomask (first mask) for forming the sealing portions 31a and 31b and the deflection preventing portion 31c, and the mask pattern is printed. Then, by developing this, a patterned photoresist film 203b is formed as shown in FIG. 4C. Since the processing accuracy in the plane direction may be lower than the processing accuracy required for a general semiconductor device, an exposure apparatus with low accuracy can be used for printing a mask pattern.

Next, as shown in FIG. 4D, the film 202a is dry-etched using the photoresist film 203b as a mask to expose the Si wafer 201a. Thus, the film 202 patterned on the Si wafer 201a
b is formed. Next, as shown in FIG. 4E, the patterned photoresist film 203b is removed.

Next, as shown in FIG. 4F, the wafer shown in FIG. 4E is etched. This etching is preferably wet etching using an alkaline solution as an etchant. As the alkaline solution, for example, ammonia or an organic ammonia-based solution is preferable. For example,
As shown in FIG. 3, in order to set the height h of the sealing portions 31a, 31b and the deflection preventing portion 31c to 50 μm, the wafer 201a
May be etched to a depth of 50 μm.

Next, as shown in FIG. 4G, the patterned film 202b is removed with hydrofluoric acid or the like. Thereby, the Si wafer 201b having the sealing portions 31a and 31b and the deflection preventing portion 31c is formed.

Next, as shown in FIG. 4H, on the front surface, the back surface, and the side wall of the Si wafer 201b, on the wafer 201b on which the sealing portions 31a and 31b and the deflection preventing portion 31c are formed, A film 204a for forming a mask pattern when etching is formed. As a material of the film 204a, for example, SiO ₂ by thermal oxidation or the like, and Si ₃ N ₄ by a CVD method or the like are preferable.

Next, a photoresist film 205a is formed on the back surface (the surface opposite to the surface on which the sealing portions 31a and 31b and the deflection preventing portion 31c are formed) of the wafer shown in FIG. 4H.

Next, through a photomask (second mask) for forming the suction holes 31d and the pin holes 31e,
The mask pattern is printed by irradiating the photoresist film 205a with ultraviolet light. Then, by developing this, as shown in FIG. 4J, a photoresist film 205b having a hole 211 for forming the suction hole 31d and a hole 212 for forming the pin hole 31e is formed.

Next, as shown in FIG. 4K, the film 204a is dry-etched using the photoresist film 205b as a mask to expose the Si wafer 201b. As a result, the film 204 patterned on the Si wafer 201b
b is formed. Next, as shown in FIG. 4L, the patterned photoresist film 204b is removed.

Next, as shown in FIG.
The wafer shown in FIG. 4L is etched until d and the pin hole 31e are formed. This etching is preferably wet etching using an alkaline solution as an etchant. As the alkaline solution, for example, ammonia or an organic ammonia-based solution is preferable.

Next, as shown in FIG. 4N, the patterned film 204b is removed with hydrofluoric acid or the like. Thereby, the wafer support table 31 is completed.

In the wafer support table 31 manufactured in this manner, the surfaces of the wafer 201a as materials become the sealing portions 31a and 31b and the deflection preventing portion 31c as they are. Therefore, the wafer 201a having sufficient surface flatness
It is not necessary to process the surface of the resultant after removing the photoresist film 203a by manufacturing the wafer support table 31 by using.

As described above, the wafer support table 31 according to this embodiment can be manufactured at a low cost by a simple method. Therefore, for example, when particles adhere to the wafer support 31 and it is difficult to remove the particles by washing, the wafer support 31 can be replaced with another wafer support 31 at low cost.

The above-mentioned wafer supporting device 3 is suitable for supporting one wafer in a process of bringing two wafers into close contact with each other. Hereinafter, the wafer support device 3
The first and second wafers are pressed against the back surface of the second wafer in a state where the first wafer is supported and the second wafer is opposed to the first wafer, so that the first and second wafers are brought into close contact with each other. The apparatus and method will be described. Such an apparatus and method are suitable for implementing a method of manufacturing a wafer having an SOI structure or the like by bonding two wafers.

FIG. 5 is a view showing a state in which two wafers are brought into close contact with each other using the wafer support device 3. In order to bring the two wafers into close contact, first, the first wafer 1 is sucked onto the wafer support 31 and the second wafer 2 is opposed to the first wafer 1. Then, in this state, pressure is applied to the substantially central portion of the back surface of the second wafer 2 by the pressure pins 6a. As a result, first, the two wafers 1 and 2 are brought into close contact with each other at the central portion, and then the contact portion gradually expands toward the outer peripheral portion,
Eventually, the entire surfaces of both wafers 1 and 2 are completely adhered. According to this method, the two wafers 1 and 2 can be brought into close contact without leaving gas between them.

When applied to the process of bringing two wafers into close contact with each other, the wafer supporting table 3 is configured such that the suction section constituted by the sealing sections 31a and 31b is positioned near the peripheral portion of the first wafer 1 (more preferably, at the end). It is preferably formed at a position in contact only with the outer peripheral portion). Further, it is preferable that the adsorbing section has an annular shape. Further, as described above, it is preferable that the wafer support 3 has the bending prevention portion 31c, and the position of the bending prevention portion 31c is determined by the sealing portions 31a and 31c.
More preferably, it is between b. Since the wafer support 3 is configured to be in contact with only the back surface of the first wafer in this manner, the surface of the first wafer 1 can be prevented from being contaminated by particles, and the first wafer can be prevented from being contaminated. It is also possible to prevent the loss of the edge portion 1 and the like.
Further, the wafer support 3 is configured to be in contact with only the vicinity of the peripheral portion, which is a part of the back surface of the first wafer, so that particles that can adhere to the wafer support 3 or the back surface of the first wafer 1 Therefore, it is possible to prevent the first wafer 1 supported on the wafer support 3 from being uneven.

Next, a wafer processing apparatus incorporating the wafer support device 3 will be described.

FIG. 6 is a perspective view schematically showing an overall configuration of a wafer processing apparatus according to this embodiment. FIG.
It is the figure which expanded a part of FIG. FIG. 8 to FIG.
8 is a cross-sectional view of the wafer processing apparatus 100 shown in FIG. 7 taken along line AA ′, showing an operation of bringing two wafers into close contact with each other.

The wafer processing apparatus 100 is an apparatus for continuously executing a process of superposing two wafers and bringing them into close contact with each other.
It is suitable for implementing a method of manufacturing a wafer having a structure such as I.

The wafer processing apparatus 100 includes a wafer support device 3 for supporting the first wafer 1 (see FIG. 5) from the back.
And a wafer moving mechanism 4 for sucking the second wafer 2 (see FIG. 5) from the back surface and facing the first wafer 1 substantially in parallel.

As described above, the wafer support device 3 is constructed by mounting the wafer support table 31 on the base 32 and adsorbing the wafer support table 31 onto the base 32 by opening the valve 19a. You.

The wafer moving mechanism 4 preferably has a structure that contacts only the back surface of the second wafer 2. In this embodiment, the groove 4 for vacuum suction of the wafer is used.
a. In order to adsorb the second wafer 2, the space in the groove 4a may be reduced in pressure. The wafer moving mechanism 4 rotates about 180 degrees about the shaft 4b while the back surface of the second wafer 2 is suctioned by the wafer suction unit 4c, and
And substantially in parallel. Note that the shaft 4b is located substantially at the center between the wafer support device 3 and the wafer suction unit 4c.

The wafer processing apparatus 100 serves as a mechanism for adjusting the gap between the two opposing wafers 1 and 2 after the first wafer 1 is placed on the wafer support device 3. A displacement detection unit 15 for measuring the thickness, a displacement detection unit 12 for measuring the thickness of the second wafer 2 after the second wafer 2 is attracted to the wafer suction unit 4c, and both displacement detection units 12, 15
Has a Z-axis stage 5 (see FIG. 8) for moving the wafer support device 3 up and down based on the measurement result to adjust the gap between the wafers 1 and 2 to a set value.

The wafer processing apparatus 100 has a pressing mechanism 6 for pressing the substantially central portion of the upper wafer 2 in a state where the two wafers 1 and 2 are supported to face each other. The pressure pins 6a of the pressure mechanism 6 are connected to the two wafers 1 and 2
After being opposed to each other, it rotates around the shaft 6b to the vicinity of the rear surface of the upper wafer 2. The pressing mechanism 6 presses the pressing pins 6a against the back surface of the upper wafer 2 and pressurizes the wafer at the same time that the wafer suction unit 4c of the wafer moving mechanism 4 releases the suction of the upper wafer 2. The two wafers 1 and 2 gradually come into close contact with each other in the outer peripheral direction from the pressurized portion, and accordingly, the gas between the wafers 1 and 2 is discharged in the outer peripheral direction. Therefore, wafer 1,
Gas is not left behind between the two.

Incidentally, the pressing of the wafer 2 by the pressing pins 6a is preferably performed substantially simultaneously with the release of the suction of the wafer 2 by the wafer suction section 4c. In this case, since the pressing operation can be started while maintaining the gap between the two wafers 1 and 2 adjusted to the set value, the quality of the wafers after the close contact can be uniformed, and Gas can be more effectively prevented from being left between the wafers 1 and 2, and furthermore, the displacement of the wafers 1 and 2 can be prevented.

The pressure mechanism 6 has a built-in vibrator (for example, a piezoelectric element) for vibrating the pressure pin 6a.
By vibrating the pressure pin 6a when pressing the
The gas between the wafers 1 and 2 can be efficiently discharged.

The control of the pressing of the wafer 2 by the pressing pins 6a may be performed at another timing. For example, after releasing the suction of the wafer 2, the gas between the wafers 1 and 2 is discharged by a predetermined amount or more. Pressurization may be performed at a predetermined timing before the operation is performed, may be performed after a certain period of time has been measured after the release of the suction of the wafer 2, or may be performed after the release of the suction of the wafer 2. It may be performed at a predetermined timing before the distance between them becomes equal to or less than a predetermined distance due to the weight of the wafer 2 or the like.

The wafer processing apparatus 100 further transfers the wafers 1 and 2 to the wafer support unit 3 and the wafer suction unit 4c, respectively.
And a wafer transfer robot 10 that receives the wafer after contact from the wafer support device 3 and a wafer alignment unit 11.

In this wafer processing apparatus 100, before starting the close contact processing of the wafers, the unprocessed wafers 1, 2
The wafer cassettes 7, 8 accommodating respectively and the wafer cassette 9 accommodating the processed wafer are arranged at predetermined positions. In this embodiment, the wafer cassettes 7 and 8 have the unprocessed wafers 1 and 2 with the back surfaces facing down.
Shall be housed in

When the start of the close contact processing of the wafer is instructed by the operation switch 16 b of the operation panel 16, the wafer transfer robot 10 attracts the back surface of the unprocessed wafer 1 stored in the wafer cassette 7 and picks up the wafer alignment unit. 11
Transport to The wafer alignment unit 11 detects the center position and the direction (for example, the position of the orientation flat and the notch) of the transferred wafer 1 by using a sensor, and adjusts the center position and the direction. Here, it is preferable that the wafer alignment unit 11 has a structure that contacts only the rear surface of the wafer 1.

Thereafter, the wafer transfer robot 10 receives the aligned wafer 1, and places it on the wafer support device 3 at a predetermined position on the load pins 13 projecting through the pin holes 31e and 32d. After the wafer 1 is placed on the load pins 13 in this manner, the wafer support device 3 is lifted, so that the wafer 1 is supported by the wafer support device 3. Since the wafer 1 is already aligned by the wafer alignment unit 11 and delivered to the wafer support device 3 while maintaining the positional relationship, it is not necessary to adjust the center position and orientation of the wafer 1 on the wafer support device 3 again. . However, a configuration in which the wafer 1 is aligned on the wafer support device 3 may be adopted.

Next, the wafer transfer robot 10 takes out the unprocessed wafer 2 from the wafer cassette 8 and performs the wafer alignment by the wafer alignment unit 11 in the same procedure as described above.
Is adjusted, and the wafer is placed at a predetermined position on the load pin 14 protruding above the wafer suction part 4c of the wafer moving mechanism 4. Thus, the wafer 2 is loaded with the load pins 1
After being placed on the wafer 4, the wafer suction unit 4c rotates around the shaft 4b until it comes into contact with the back surface of the wafer 2, and the pressure in the groove 4a is reduced, so that the wafer 2 is suctioned by the wafer suction unit 4c. You. As described above, since the wafer 2 is already aligned by the wafer alignment unit 11 and is sucked by the wafer suction unit 4c while maintaining the positional relationship, it is necessary to adjust the center position and the orientation of the wafer 2 again at the time of suction. There is no. It should be noted that a configuration in which the load pins 14 are housed downward instead of rotating the wafer suction portion 4c when the wafer 2 is suctioned is also effective.

With the wafers 1 and 2 thus supported by the wafer support device 3 and the wafer suction unit 4c, the displacement detection units 15 and 12 measure the thickness of the wafers 1 and 2, respectively. Specifically, the displacement detection units 15 and 12
The sensors 15a and 12a are moved to the upper portions of the wafers 1 and 2, for example, the wafers 1 and 2 are irradiated with light, and the thicknesses of the wafers 1 and 2 are respectively measured based on the reflected light.

When the measurement of the thickness of the wafers 1 and 2 is completed,
As described above, the wafer suction unit 4c rotates about 180 degrees about the shaft 4b, and makes the wafer 2 face the wafer 1 substantially in parallel. Thereafter, the gap between the wafers 1 and 2 is adjusted by the Z-axis stage 5, and the pressure is applied to the wafer 2 by the pressing pins 6a, thereby completing the close contact processing.

When the contact processing is completed, the wafer supporting device 3
Is lowered by the Z-axis stage 5, and the processed wafer is supported by the load pins 13. After that, the wafer transfer robot 10 receives the processed wafer and stores it in the wafer cassette 9.

By repeating such a procedure, a plurality of wafers stored in the wafer cassettes 7 and 8 can be continuously processed.

Next, the operation of the wafer processing apparatus 100 when two wafers are brought into close contact will be described with reference to FIGS.

The wafer 1 is moved by the wafer transfer robot 10.
8 are placed on the load pins 13 and 14, respectively, FIG.
As shown in (2), the Z-axis stage 5 raises the wafer supporting device 3 to a predetermined position for supporting the wafer 1, and the wafer moving mechanism 4 moves the wafer around the axis 4b to a predetermined position where the wafer 2 can be sucked. The suction unit 4c is rotated.

Next, as shown in FIG.
The 5 and 12 sensors 15a and 12a move onto the wafers 1 and 2, and the thicknesses of the wafers 1 and 2 are measured respectively. And
After the thicknesses of the wafers 1 and 2 are measured, the sensors 15a and 1
2a returns to the initial position shown in FIG.

Next, as shown in FIG. 10, the wafer moving mechanism 4 moves the wafer suction portion 4c about one axis about the shaft 4b.
By rotating the wafer by 80 degrees, the wafers 1 and 2 are substantially horizontally opposed, and based on the thickness of the wafers 1 and 2 measured earlier,
The height of the wafer support device 3 is adjusted by the Z-axis stage 5, and the gap between the wafers 1 and 2 is set to a set value. This gap is, for example, 20-100 μm at the center of the wafer.
m, and more preferably about 30 to 60 μm. Further, the wafer processing apparatus 100 sucks the peripheral portion of the back surface of the wafer 1 onto the suction surface of the peripheral portion 3d of the wafer support device 3 by opening the valve 19b. Thereby, the wafer 1 is corrected so as to form a substantially flat surface.

Next, as shown in FIG. 11, the pressure pin 6a is rotated about the shaft 6b, and is rotated to the vicinity of the back surface of the wafer 2 (for example, to a position substantially in contact with the back surface of the wafer 2).

Then, as shown in FIG. 12, the back surface of the wafer 2 is pressed by the pressing pins 6a simultaneously with the release of the suction of the wafer 2 by the wafer suction section 4c. This allows
Wafers 1 and 2 gradually come into close contact from the center toward the outer periphery, and finally come into close contact with the entire surface.

Next, after returning the pressure mechanism 6 to the original state (the state shown in FIG. 8), the wafer suction unit 4c is returned to the original state (the state shown in FIG. 8). Then, after the valve 19b is closed and the inside of the suction groove 3a is brought to the atmospheric pressure (after the suction of the wafer 1 is released), the wafer support device 3 is lowered, and the wafer after the close contact is supported by the load pins 13. State. In this state, the wafer transfer robot 10 sucks the lower part of the wafer after the close contact, and transfers and stores the wafer to the wafer cassette 9.

FIG. 13 is a block diagram showing a configuration example of a control system of the wafer processing apparatus 100. The control unit 17 is controlled by the CPU 17a operating based on the program 17b.
A wafer transfer robot 10, a wafer alignment unit 11,
The displacement detectors 12 and 15, the Z-axis stage 5, the wafer moving mechanism 4, the pressurizing mechanism 6, the panel 16, and the valve controller 19 are controlled.

The valve controller 19 has a first valve driver 19c for controlling the opening and closing of the valve 19a and a second valve driver 19d for controlling the opening and closing of the valve 19b. The units 19c and 19d are controlled by the control unit 17. The attachment / detachment of the wafer support table 31, that is, the opening / closing of the valve 19a, is controlled based on the operation of the operation switch 16b of the panel section 16.

FIG. 14 is a flowchart showing a control procedure by the program 17b. Hereinafter, the operation of the control system of the wafer processing apparatus 100 will be described with reference to this flowchart.

When the start of the contact processing is instructed by operating the operation switch 16b, first, in step S101, each component connected to the control system 17 is initialized. In this initialization step, the wafer cassette 7,
Confirmation of the presence and location of 8, 9 and the like is also performed. If the preparation is not completed, a warning is issued to the operator by, for example, displaying that fact on the display panel 16a.

In step S102, the wafer transfer robot 10 is controlled to suck the wafer 1 stored in the wafer cassette 7, and in step S103, the sucked wafer 1 is transferred to the wafer alignment unit 11, where the wafer 1 is transferred. (Center position, orientation).
Then, in step S104, the wafer transfer robot 10 is controlled to place the wafer 1 at a predetermined position on the load pins 13 projecting above the wafer support device 3, and the Z-axis stage 5 is controlled to control the wafer support device 3 Is raised to a predetermined position.

In step S105, the wafer transfer robot 10 is controlled to suck the wafer 2 stored in the wafer cassette 8, and in step S106, the wafer 2 is transferred to the wafer alignment unit 11, where the wafer 2 is aligned (centered). Position, direction). And step S
At 107, the wafer transfer robot 10 is controlled to
Load pins 1 projecting wafer 2 onto wafer suction portion 4c
The wafer suction unit 4c is mounted at a predetermined position on the wafer moving unit 4 and the rotation motor 4d of the wafer moving mechanism 4 is controlled to rotate the wafer suction unit 4c about the shaft 4b by a predetermined angle, and the wafer 2 is suctioned by the wafer suction unit 4c. Let it.

In step S108, the driving section 15b of the displacement detecting section 15 is controlled to move the sensor 15a to a predetermined position on the wafer 1, and the thickness of the wafer 1 is measured by the sensor 15a.

In step S109, the driving section 12b of the displacement detecting section 12 is controlled to move the sensor 12a to a predetermined position on the wafer 2, and the thickness of the wafer 2 is measured by the sensor 12a.

In step S110, the wafer moving mechanism 4
The rotation motor 4d is controlled to rotate the wafer suction section 4c about the axis 4b by about 180 degrees, and the wafers 1 and 2 are rotated.
Are placed substantially horizontally.

In step S111, data for adjusting the gap between the wafers 1 and 2 to a set value is created based on the measurement results of the thicknesses of the wafers 1 and 2, and the Z-axis stage 5 is created based on the data. To adjust the gap between the wafers 1 and 2.

At step S112, the first wafer 1 is sucked onto the wafer support 31 by opening the valve 19b by the first valve driving section 19d.

In step S113, the rotation motor 6d of the pressure mechanism 6 is controlled to rotate the pressure pins 6a about the shaft 6b.
It is assumed that the front end of “a” is substantially in contact.

In step S114, the wafer suction section 4c
To release the suction of the wafer 2. Then, in step S115, the rotation motor 6d and the vibrator 6c of the pressure mechanism 6 are controlled to press the back surface of the wafer 2 with the pressure pins 6a and to vibrate the pressure pins 2. By executing step S115 immediately after execution of step S114, the release of the suction of the wafer 2 and the pressurization can be performed substantially simultaneously. However, after the execution of step S114, the pressurization can be started, for example, after measuring a predetermined time.

When the close contact of the wafers 1 and 2 is completed, in step S116, the rotation motor 6d of the pressure mechanism 6 is controlled to return the pressure pins 6a to the initial position. Then, in step S117, the rotation motor 4d of the wafer moving mechanism 4 is controlled to return the wafer suction unit 4c to the initial position.

Then, in step S118, the valve 1
9b is closed and the inside of the suction grooves 3a and 3b is returned to the atmospheric pressure to release the suction of the wafer 1, and then the step S
In 119, the Z-axis stage 5 is controlled to lower the wafer support device 3 to return to the initial position. As a result, the wafer after the close contact is supported by the load pins 13.

In step S120, the wafer transfer robot 10 is controlled so that the wafers having been brought into close contact with each other are stored in the wafer cassette 9.
Transported and stored.

In step S121, it is determined whether or not the contact processing has been completed for all the wafers stored in the wafer cassettes 7 and 8. If unprocessed wafers remain, the flow returns to step S102 to repeat the processing. . On the other hand, if it is determined that the contact processing has been completed for all the wafers, a series of processing is terminated. At this time, for example, the fact is displayed on the display panel 16a or the like, and the operator is notified by a buzzer or the like. It is preferable to notify.

As described above, this wafer processing apparatus 100
According to this, 1) since the pressurization is started in accordance with the release of the suction of the upper wafer 2, the gas between the wafers 1 and 2 can be reliably discharged in the outer peripheral direction. Since the upper wafer 2 does not slip in the opposed state, 2
It is possible to accurately align the two wafers 1 and 2,
3) Since the gap between the wafers 1 and 2 can be adjusted to an appropriate distance, the quality of the manufactured wafer can be made uniform, and the work of pre-sorting the wafers 1 and 2 is not required, 4) It is possible to prevent the surfaces of the wafers 1 and 2 from being contaminated by particles, 5) to prevent the loss of the outer peripheral portion of the wafer, and 6) to apply vibration to the wafer when pressurized. The gas left between the wafers can be further reduced.

According to the wafer processing apparatus 100, only the sealing portions 31a and 31b and the deflection preventing portion 31c of the wafer support table 31 are in contact with the back surface of the first wafer 1. The first wafer can be supported in a substantially planar state even when particles adhere to the center of the first wafer 1 or the center of the back surface of the first wafer 1. In other words, it is possible to prevent generation of irregularities on the supported wafer 1 due to particles that can adhere to the wafer support base or the central portion of the first wafer. Therefore, when two wafers are brought into close contact with each other, it is possible to effectively prevent the substrate from being left behind between the wafers.

Further, according to the wafer processing apparatus 100, since the wafer support table 31 manufactured by processing a wafer is employed, there is also a problem of contamination (for example, metal contamination) due to the constituent material of the wafer support table. Will be resolved.

[Application Example of Wafer Processing Apparatus] Next, an application example of the above-described wafer processing apparatus will be described. FIG.
It is a figure showing an example of a manufacturing process of a wafer which has a structure etc.

First, a single crystal Si wafer 501 for forming the first wafer 1 is prepared, and a porous Si layer 502 is formed on the main surface thereof (see FIG. 15A). Next, at least one non-porous layer 503 is formed on the porous Si layer 502 (see FIG. 15B). As the non-porous layer 503, for example, a single-crystal Si layer,
Preferred are a layer, an amorphous Si layer, a metal film layer, a compound semiconductor layer, a superconductor layer, and the like. The non-porous layer 503 has M
An element such as an OSFET may be formed.

Next, on the non-porous layer 503, SiO ₂
A layer 504 is formed, and this is used as a first wafer 1 (FIG. 15).
(See (c)), and housed in the wafer cassette 7 with the SiO ₂ layer 504 facing up.

Further, a second wafer 2 is separately prepared and is housed in a wafer cassette 8 with its surface facing upward.

When the wafer processing apparatus is operated in this state, the first wafer 1 and the second wafer 2 are brought into close contact with each other with the SiO 2 layer 504 being sandwiched on the wafer support table (see FIG. 15D). ), And then housed in wafer cassette 9.

Thereafter, the wafer in close contact (FIG. 15D)
However, the bonding may be strengthened by performing an anodic bonding treatment, a pressure treatment, or a heat treatment as necessary, or by combining these treatments.

As the second wafer 2, a Si wafer, S
An i-wafer having a SiO ₂ layer formed thereon, a light-transmitting wafer such as quartz, sapphire, or the like is preferable. However, the second wafer 2 only needs to have a sufficiently flat surface to be bonded, and may be another type of wafer.

Next, with the porous Si layer 503 as a boundary,
The first wafer 1 is removed from the second wafer 2 (FIG. 15).
(See (e)), the porous Si layer 502 is selectively etched and removed. FIG. 15F schematically shows a wafer obtained by the above manufacturing method.

According to this manufacturing method, the two wafers are brought into close contact with each other while the gas between the wafers is appropriately discharged.
High quality wafers can be manufactured.

[0118]

According to the present invention, for example, it is possible to provide a substrate support that can be manufactured at low cost.

[0119]

[Brief description of the drawings]

FIG. 1 is a plan view showing a configuration of a wafer support according to a preferred embodiment of the present invention.

FIG. 2 is a sectional view of a part of the wafer support shown in FIG. 1;

FIG. 3 is a cross-sectional view showing a configuration of a wafer support device including the wafer support table shown in FIG.

FIG. 4A is a diagram illustrating an example of a manufacturing process of a wafer support base.

FIG. 4B is a diagram showing an example of a manufacturing process of the wafer support base.

FIG. 4C is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4D is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4E is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4F is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4G is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4H is a view showing an example of the manufacturing process of the wafer support base.

FIG. 4I is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4J is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4K is a view showing an example of the manufacturing process of the wafer support base.

FIG. 4L is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4M is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 4N is a diagram showing an example of the manufacturing process of the wafer support base.

FIG. 5 is a diagram illustrating a state in which two wafers are brought into close contact with each other using a wafer support device.

FIG. 6 is a perspective view schematically showing an entire configuration of a wafer processing apparatus.

FIG. 7 is an enlarged view of a part of FIG. 6;

FIG. 8 is a sectional view of the wafer processing apparatus shown in FIGS.
It is sectional drawing cut | disconnected by the line.

FIG. 9 is a sectional view of the wafer processing apparatus shown in FIGS.
It is sectional drawing cut | disconnected by the line.

FIG. 10 shows the wafer processing apparatus shown in FIGS. 6 and 7 as A-
It is sectional drawing cut | disconnected by the A 'line.

FIG. 11 shows the wafer processing apparatus shown in FIGS. 6 and 7 as A-
It is sectional drawing cut | disconnected by the A 'line.

FIG. 12 shows a wafer processing apparatus shown in FIGS.
It is sectional drawing cut | disconnected by the A 'line.

FIG. 13 is a block diagram illustrating a configuration example of a control system of the wafer processing apparatus.

FIG. 14 is a flowchart showing a control procedure by a program.

FIG. 15 is a diagram illustrating an example of a manufacturing process of a wafer having an SOI structure and the like.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 1st wafer 2 2nd wafer 3 Wafer support device 31 Wafer support base 31a, 31b Sealing part 31c Deflection prevention part 31d Suction hole 31e Pin hole 32 Base 32a Groove 32b, 32c Suction hole 32d Pin hole 4 Wafer moving mechanism 4a Groove 4b Axis 4c Wafer Suction Part 4d Rotating Motor 5 Z-Axis Stage 6 Pressing Mechanism 6a Pressing Pin 6b Axis 6c Vibrator 6d Rotating Motor 7-9 Wafer Cassette 10 Wafer Transfer Robot 11 Wafer Alignment Unit 12,15 Displacement Detectors 12a, 15a Sensors 12b, 15b Drives 13, 14 Load pins 16 Panel 16a Display panel 16b Operation panel 17 Control 17a CPU 17b Program 18a, 18b Pipe 19 Valve control 19a, 19b Valve 19c First valve drive 19d No. Valve drive section 20 pump

Claims (28)

[Claims] 1. A substrate support comprising a silicon material. 2. A substrate support formed by processing a silicon wafer. 3. The substrate support according to claim 2, further comprising a suction portion for sucking a substrate to be supported. 4. The substrate support according to claim 3, wherein the suction unit is formed by a lithography technique. 5. The substrate support according to claim 3, wherein the suction unit is formed by etching a silicon wafer. 6. The substrate support according to claim 3, wherein the suction unit is formed by wet etching a silicon wafer. 7. The suction unit according to claim 1, wherein the suction unit includes a sealing unit for vacuum-sucking the substrate, and a suction hole for discharging gas in a space surrounded by the sealing unit. The substrate support according to any one of claims 4 to 6. 8. The double sealing portion is provided along the outer periphery of the substrate to be supported, and the suction hole communicates with the inside of the double sealing portion. The substrate support according to claim 7, wherein: 9. The sealing portion according to claim 7, wherein the sealing portion protrudes in a dike shape with respect to the periphery thereof.
A substrate support according to any one of the above. 10. The substrate support according to claim 9, wherein only the sealing portion contacts the substrate when the substrate is sucked. 11. The substrate support according to claim 7, further comprising a bending preventing portion for preventing the substrate from bending when the substrate is sucked. 12. The substrate support according to claim 11, wherein the deflection preventing portion is disposed at a position sandwiched by the sealing portion. 13. The substrate support according to claim 11, wherein only the sealing portion and the deflection preventing portion contact the substrate when the substrate is sucked. 14. The device according to claim 11, wherein the surfaces of the sealing portion and the deflection preventing portion that come into contact with the substrate to be supported are substantially in the same plane. A substrate support according to any one of the above. 15. The substrate support according to claim 3, wherein the suction unit is disposed at a position where the vicinity of a peripheral portion of the substrate to be supported can be suctioned. Stand. 16. The apparatus according to claim 2, wherein a pin hole for passing a load pin for lifting a substrate to be supported on the substrate support base is provided so as to penetrate the main body.
The substrate support according to claim 15. 17. The substrate support according to claim 2, wherein the silicon wafer is a silicon wafer that complies with SEMI standards, JAIDA standards, and other standards. 18. The method according to claim 1, wherein:
13. A substrate processing apparatus, comprising: the substrate support according to any one of the preceding items, and performing processing on a substrate supported by the substrate support. 19. A substrate processing apparatus for superposing two substrates on each other and bringing them into close contact with each other, comprising: an attachment / detachment mechanism for attaching / detaching the substrate support base according to claim 1; Pressing means for pressing the second substrate in the direction of the first substrate in a state where the second substrate is opposed to the first substrate supported by the substrate support table. A substrate processing apparatus comprising: 20. The substrate processing apparatus according to claim 19, wherein the pressurizing unit presses a substantially central portion of the second substrate. 21. The first supporter supported by the substrate supporter.
Substrate operating means for releasing the support of the second substrate after supporting the second substrate on the second substrate, and wherein the pressing means releases the support of the second substrate by the substrate operating means. 21. The substrate processing apparatus according to claim 19, wherein the second substrate is pressurized in accordance with the condition. 22. The substrate supporter supports a first substrate substantially horizontally, and the substrate operating means supports the second substrate substantially horizontally above the first substrate and then supports the second substrate. 22. The substrate processing apparatus according to claim 21, wherein the support of the substrate is released. 23. Any one of claims 1 to 17
13. A substrate processing method, wherein a substrate is processed using the substrate support according to any one of the above items. 24. A substrate processing method, wherein a substrate is processed using the substrate processing apparatus according to any one of claims 18 to 22. 25. An SOI comprising the substrate processing method according to claim 23 in a part of the process.
Substrate manufacturing method. 26. Any one of claims 1 to 17
A cleaning method, wherein the substrate supporting table described in the paragraph is accommodated in a wafer cassette for accommodating a wafer for manufacturing a semiconductor device and cleaned. 27. A method of handling a substrate processing apparatus according to claim 18, wherein the step of removing the substrate support from the substrate processing apparatus, and the step of removing the removed substrate support from a semiconductor device. A step of accommodating the wafer in a wafer cassette for accommodating a wafer for manufacturing and cleaning; and mounting the substrate support having been cleaned on the substrate processing apparatus. Handling method. 28. A method of manufacturing a substrate support, comprising: forming an SiO ₂ film so as to cover an entire silicon wafer; and forming a first photoresist film on the SiO ₂ film on one surface. Patterning the first photoresist film to expose a portion of the SiO ₂ film where a sealing portion for vacuum suction is to be formed; and etching the exposed portion of the SiO ₂ film to expose the silicon wafer. Performing a step of removing the remaining first photoresist film; a step of etching the exposed portion of the silicon wafer to a predetermined depth; and a step of forming a SiO ₂ film so as to cover the entire silicon wafer. Forming a second photoresist film on the SiO ₂ film on the other surface; and patterning the second photoresist film to form a portion of the SiO ₂ film where a suction hole for vacuum suction is to be formed. ₂₎ exposing the film, etching the exposed portion of the SiO ₂ film to expose the silicon wafer, removing the remaining second photoresist mask, etching the exposed portion of the silicon wafer Forming a suction hole penetrating through the silicon wafer by removing the remaining SiO ₂ film.