JPH06204330A - Wafer transferring cassette and semiconductor processing device - Google Patents

Abstract

PURPOSE:To provide a wafer transferring cassette and a semiconductor processing device both simple in structure, wherein a wafer can be kept free from particles and processed without being damaged. CONSTITUTION:A wafer cassette 108 is formed of plane member, and an opening 108a of the same shape with a wafer is provided to the center of the cassette 108 where a wafer is fitted. An ring-shaped stepped member 108b which supports the outer peripheral edge of the wafer is provided throughout the lower part of the inner wall of the opening 108a. A wafer seal 107 is provided to the upside of the ring-shaped stepped member 108b, and the wafer is placed on the wafer seal 107. The wafer cassette 108 where the wafer is housed as mentioned above can be loaded on or unloaded from a semiconductor processing device as it is, so that a wafer can be processed in a noncontact manner after it is housed in the wafer cassette 108.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wafer transfer cassette and a semiconductor processing apparatus used in a semiconductor element manufacturing process.

[0002]

2. Description of the Related Art In general, a wafer process comprises a combination of several basic processes such as a cleaning process, an oxidizing process, an impurity introducing process, a thin film forming process, etc., which are repeatedly performed with a lithography process as an axis. The processing in each of the above steps is carried out in a process device such as a cleaning device, an oxidizing device, an ion implantation device, and a thin film forming device.
Conventionally, wafers are transferred between these process devices by a wafer case, and the transferred wafers are attached to and detached from the process devices by direct contact with tweezers, vacuum tweezers, transfer arms, and the like.

Among the above-mentioned process apparatuses, a conventional anodizing apparatus for making a wafer porous will be described below.

FIG. 5 is a schematic sectional view of an example of a conventional anodizing apparatus. As shown in FIG. 5, this anodizing apparatus has a lower tank 503 in which a positive electrode 501 is arranged and an upper tank 504 in which a negative electrode 502 is arranged,
The wafer 512 made of i is sandwiched and mounted between the lower tank 503 and the upper tank 504. Further, an upper tank seal 506 and a lower tank seal 505 are provided on the upper tank 504 and the lower tank 503, respectively, at the portions in contact with the wafer 512.

When mounting the wafer 512 on the anodizing apparatus, first, the transfer arm 508 on which the wafer 512 is placed is moved between the upper tank 504 and the lower tank 503,
Further, the wafer 512 is moved downward and the wafer 512 is placed on the lower tank 503. Next, the transfer arm 508 is removed, and the upper tank 504 is lowered to press the wafer 512. Thereby, the upper tank 504 and the lower tank 503 are sealed.

Then, the sealed upper tank 504 is filled with the HF solution, and the wafer 512 and the negative electrode 502 are electrically contacted. On the other hand, the lower tank 503 is filled with an electrolytic solution,
Electrical contact is made between the wafer 512 and the positive electrode 501. When an electric potential is applied between the electrodes 501 and 502 in this state, the upper surface of the wafer 512 is made porous by the HF solution.

FIG. 6 is a schematic sectional view of another example of the conventional anodizing apparatus. This anodizing apparatus has a pressing mechanism 613 provided inside the lower tank 603 so as to be vertically movable by the operation of a lever 613a. Other configurations are similar to those shown in FIG. When mounting the wafer 612 on the anodizing apparatus, the wafer 612 is placed on the pressing mechanism 613 by the transfer arm 608 while the upper end of the pressing mechanism 613 is projected from the upper end of the lower tank 603. The transfer arm 608 is removed. Next, the pressing mechanism 613 is lowered to lower the wafer 61.
2 is placed on the lower tank 603. After that, the upper surface of the wafer 612 is made porous in the same manner as shown in FIG.

[0008]

However, in the above-mentioned wafer process, when the wafer is mounted on the process equipment, the wafer is once held from the wafer case which accommodates the wafer by the transfer arm or the like, and then the wafer is transferred to the equipment. This is a two-step operation of mounting and dismounting, and since the transfer arm and the like hold the wafer in each process, there is a problem that particles are easily attached to the wafer or scratches occur. Further, in the processing apparatus, there is a problem in that the wafer, which must be handled carefully, must be directly handled, and the structure becomes very complicated.

The above-mentioned problems occur not only in the anodization process on the wafer, but also in the ion implantation process, the cleaning process, the thin film forming process and the like.

Particularly in the anodizing apparatus shown in FIG. 5, the wafer cannot be placed in the lower tank unless the lower tank seal is provided inside the portion where the transfer arm supports the wafer. The contact area between the liquid and the wafer is reduced. As a result, the electric field at the peripheral edge of the wafer becomes non-uniform, and the speed at which the wafer becomes porous becomes slower at the peripheral edge of the wafer than at the central portion.

On the other hand, in the anodizing apparatus shown in FIG. 6, by providing the pressing mechanism, the position of the lower tank seal can be made the same as the position where the transfer arm supports the wafer. Although the contact area between the electrolytic solution and the wafer can be increased, the pressing mechanism provided in the lower tank causes non-uniformity of the electric field applied to the wafer and turbulence of the liquid flow, and the speed of porosification is increased. There was a problem that it became non-uniform in the plane. Further, there is a problem that the device configuration becomes complicated by providing the pressing mechanism.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a wafer transfer cassette and a processing apparatus capable of suppressing the adhesion of particles to a wafer and the generation of scratches with a simple structure.

[0013]

In order to achieve the above object, a wafer transfer cassette of the present invention comprises a flat plate member which can be attached to and detached from a wafer mounting portion of a semiconductor process apparatus, and is formed on the flat plate member. An opening into which one surface side of the wafer to be processed is inserted, and a supporting portion integrally provided on an inner wall of the opening for supporting an outer peripheral edge portion of the wafer inserted into the opening. .

Further, the supporting portion may be provided all around the inner wall of the opening, and a seal member may be provided at a contact portion of the supporting portion with the wafer. A notch reaching the opening may be formed in one portion of the side wall of the flat plate-like member, through which a wafer holding means for attaching and detaching the wafer to and from the opening can pass.

In the semiconductor processing apparatus of the present invention, the wafer mounting portion for mounting the wafer to be processed has a structure in which the wafer transfer cassette of the present invention can be attached and detached.

[0016]

According to the invention of the cassette for carrying a wafer as described above, the wafer to be processed is inserted into the opening formed in the flat member, and is integrally provided on the inner wall of the opening. The outer peripheral edge portion is supported by the provided support portion. The flat member supporting the wafer in this way is
Since the wafer can be attached to and detached from the wafer mounting portion of the semiconductor process device, the wafer is directly attached to the semiconductor process device without being taken out from the opening. As a result, once the wafer is set in the opening of the wafer transfer cassette, the wafer process is performed thereafter without contacting the wafer, and the adhesion of particles to the wafer and the generation of scratches are suppressed.

According to another aspect of the invention of the semiconductor processing apparatus, the wafer mounting portion on which the wafer to be processed is mounted is
Since the wafer transfer cassette of the present invention has a detachable structure, it is not necessary for the semiconductor process apparatus itself to have a complicated mechanism to load and unload the wafer without contacting the surface of the wafer. Realized without.

[0018]

Embodiments of the present invention will now be described with reference to the drawings.

(First Embodiment) FIG. 1 is a schematic sectional view of an anodizing apparatus using a first embodiment of a wafer transfer cassette (hereinafter referred to as "wafer cassette") of the present invention.
This anodizing apparatus is an example of a process apparatus used for a wafer process, and is used in the semiconductor element manufacturing process of the wafer 11
This is for making the surface of No. 2 porous. As shown in FIG. 1, a cylindrical lower tank 103 is fixed to a base 100 of the anodizing apparatus via a positive electrode 101. The lower tank 103 contains the lower tank 10 when the wafer 112 is made porous.
3 is formed with an electrolytic solution circulation path 110 for circulating the electrolytic solution to be injected into the lower tank 103.
05 is provided.

A cylindrical upper tank 104 is provided above the lower tank 103 so as to be vertically movable, and the upper end of the upper tank 104 is closed by a negative electrode 102 fixed to the upper end surface of the upper tank 104. It is peeling. Similar to the lower tank 103, the upper tank 104 also has an HF solution circulating path 109 for circulating the HF solution injected into the upper tank 104 when the wafer 112 is made porous.
In addition, the upper tank seal 106 is provided on the lower end surface of the upper tank 104, which is in contact with the outer peripheral portion of the wafer 112, over the entire circumference thereof. Also, the upper tank 10
A laminarization mesh 111 for laminarizing the HF solution and the electrolytic solution, which are respectively injected, is provided inside the lower tank 4 and the lower tank 103.

On the other hand, the wafer cassette 108 on which the wafer 112 is placed is movably provided between the lower tank 103 and the upper tank 104. Below, this wafer cassette 10
The configuration of No. 8 will be described with reference to FIG. FIG. 2 is a schematic perspective view of the wafer cassette shown in FIG. As shown in FIG. 2, the wafer cassette 108 is made of a flat plate-shaped member, and an opening 108 having the same shape as the outer shape of the wafer 112, into which the wafer 112 (see FIG. 1) is fitted, is formed in the center thereof.
a is formed. Below the inner wall of the opening 108a, a step portion 108b as a supporting portion for supporting the outer peripheral edge portion of the wafer 112 fitted in the opening 108a is provided.
It is integrally provided over the entire circumference of the inner wall of the opening 108a. A wafer seal 107 as a sealing member is provided on the upper surface of the step portion 108b over the entire circumference thereof, and the wafer 112 is placed on the wafer seal 107.

Based on the configuration described above, the wafer cassette 108 on which the wafer 112 is mounted is composed of the lower tank 103 and the upper tank 1.
It is moved between 04 and 04 and placed on the lower tank 103 as it is. After the wafer cassette 108 is placed on the lower tank 103, the wafer cassette 108 is covered with the upper tank 104, and a downward force is applied to the upper tank 104 by the weight of the upper tank 104 or a pressing means (not shown). As a result, the wafer 1
12 and the upper tank seal 106 are in close contact with each other, and the inside of the upper tank 104 is sealed. Similarly, the wafer 112 and the wafer seal 1
07 and the wafer cassette 108 and the lower tank seal 105 are in close contact with each other, and the inside of the lower tank 103 is sealed.

After sealing the upper tank 104 and the lower tank 103, the upper tank 104 is filled with the HF solution, and the wafer 112 and the negative electrode 1 are
Make electrical contact with 02. On the other hand, the lower tank 103 is filled with an electrolytic solution to make electrical contact between the wafer 112 and the positive electrode 101. At this time, the HF solution with which the upper tank 104 is filled is circulated through the HF solution circulation path 109, and becomes a laminar flow by the laminarization mesh 111 provided in the upper tank 104, and is applied to the wafer 112.
Similarly, the electrolytic solution with which the lower layer 103 is filled is circulated by the electrolytic solution circulation path 110, and becomes a laminar flow by the laminarized mesh 111 provided in the lower tank 103, and is applied to the wafer 112. In this state, each electrode 101, 10
When a potential is applied between the two, the upper surface of the wafer 112 is made porous by the HF solution.

As described above, in this embodiment, the wafer 11
Wafer 11 with 2 placed on wafer cassette 108
2 can be made porous, so that the wafer 112
The wafer 112 can be attached to and removed from the anodizing apparatus without touching the surface of the wafer 112, and the occurrence of contamination and scratches on the surface of the wafer 112 can be suppressed. Also, the wafer 1
Since the back surface of 12 is supported by a small area, an electric field can be uniformly applied to the wafer 112.
The porosity of 12 can be made uniform within the wafer surface.

The anodization of the wafer 112 causes H
It has been confirmed by experiments that particles increase in the F solution, and the number thereof is several thousands in the HF solution 1 cc with a size of 0.2 μm or more. Therefore, in order to reduce the contamination of the surface of the wafer 112 due to the particles, it is effective to provide a filtering mechanism in the HF solution circulation path 109 to filter the particles in the HF solution.

In the present embodiment, an example in which the wafer cassette 108 is incorporated in the anodizing process has been described. However, if the wafer cassette 108 is incorporated in the processes before and after the anodizing process, the wafer 112 is transferred to the wafer cassette 1.
It is possible to go through a plurality of steps without removing from the wafer 08, and it is possible to further suppress the occurrence of contamination and scratches on the surface of the wafer 112. Further, since it becomes unnecessary to attach and detach the wafer 112 from the wafer cassette 108 between processes,
Since the wafer 112 is easily handled, the time from the end of the previous process to the start of the next process can be shortened.
The processing of the wafer 112 can be performed efficiently. For example, when the anodization process described in this embodiment is completed, the wafer 112 that has undergone anodization is transferred to the wafer cassette 108.
By moving the wafer 112 to the cleaning device while being mounted on the wafer, the cleaning process in the next step can be performed without the need to attach and detach the wafer 112 from the wafer cassette 108. In this case, the cleaning device needs to have a structure capable of attaching and detaching the wafer 112 together with the wafer cassette 108. Similarly, when incorporating into other process equipment such as ion implantation equipment and thin film forming equipment,
It is necessary that the wafer 112 can be attached and detached together with the wafer cassette 108.

(Second Embodiment) In the first embodiment, the wafer cassette which can be used also in the anodizing apparatus has been described. However, in the present embodiment, when the process which requires the liquid sealing is not performed, that is, the ion cassette is used. A wafer cassette used in a process that does not require liquid sealing such as injection, cleaning, and vapor deposition will be described.

FIG. 3 is a schematic perspective view of the second embodiment of the wafer cassette of the present invention. Wafer cassette 2 of this embodiment
In addition to the opening 208a and the step portion 108b similar to those of the first embodiment, the groove 08 is formed with a notch 208c reaching from one part of the side wall of the wafer cassette 208 to the opening 208a. This allows the wafer to be easily attached to and detached from the wafer cassette 208 by using vacuum tweezers or a table.

(Third Embodiment) FIG. 4 is a schematic perspective view of a third embodiment of the wafer cassette of the present invention. The wafer cassette 308 of this embodiment has four openings 308a similar to those of the first embodiment. Each opening 308a
Each of them has a step portion 308 similar to that of the first embodiment.
b is formed, and a wafer seal 307 is provided on the upper surface of each step 308b. As a result, four wafers can be placed on one wafer cassette 308, so that the wafers can be processed more efficiently.

In this embodiment, an example of the wafer cassette 308 capable of mounting four wafers is shown, but the number may be increased or decreased as necessary. When used in a process that does not require liquid sealing, each wafer seal 307
Is not necessary, and in addition, each opening 308
The cut 208c described in the second embodiment for each a (see FIG. 3)
May be formed.

[0031]

Since the present invention is configured as described above, it has the following effects.

In the wafer transfer cassette of the present invention, an opening into which a wafer is inserted and a support portion that supports the wafer inserted into the opening are provided in a flat plate-like member that is detachable from the wafer mounting portion of the semiconductor processing apparatus. By providing the wafer, once the wafer is set in the wafer transfer cassette, it is possible to attach and detach the wafer to and from the semiconductor process device without contacting the wafer thereafter. Occurrence can be suppressed.

Further, by providing the support portion over the entire circumference of the inner wall of the opening and providing the seal member at the contact portion of the support portion with the wafer, for example, in an anodizing apparatus,
It can also be applied to a semiconductor process device that requires a liquid seal. In particular, when applied to an anodizing apparatus as a semiconductor process apparatus, the wafer can be supported in a minimum area, so that the electric field applied to the wafer becomes uniform, and the rate of porosification of the wafer is increased. Can be uniform within.

Further, at a part of the side wall of the flat member,
By forming a notch reaching the opening through which the wafer holding means for mounting and demounting the wafer can pass, the wafer can be easily mounted and dismounted from the wafer transfer cassette.

The semiconductor processing apparatus of the present invention is
Since the wafer mounting portion on which the wafer to be processed is mounted has the structure for attaching and detaching the wafer transfer cassette of the present invention, the wafer can be mounted on or removed from the semiconductor processing apparatus without coming into contact with the surface of the wafer. Can be realized without requiring a complicated mechanism in the semiconductor process device itself. Also,
Since the wafer can be transferred between the respective processes for each wafer transfer cassette, the wafer can be easily handled and the wafer can be efficiently processed.

[Brief description of drawings]

FIG. 1 is a schematic sectional view of an anodizing apparatus using a first embodiment of a wafer transfer cassette according to the present invention.

FIG. 2 is a schematic perspective view of the wafer cassette shown in FIG.

FIG. 3 is a schematic perspective view of a second embodiment of the wafer transfer cassette according to the present invention.

FIG. 4 is a schematic perspective view of a wafer transfer cassette according to a third embodiment of the present invention.

FIG. 5 is a schematic sectional view of an example of a conventional anodizing apparatus.

FIG. 6 is a schematic cross-sectional view of another example of the conventional anodizing apparatus.

[Explanation of symbols]

 100 Base 101 Positive Electrode 102 Negative Electrode 103 Lower Tank 104 Upper Tank 105 Lower Tank Seal 106 Upper Tank Seal 107, 307 Wafer Seal 108, 208, 308 Wafer Cassette 108a, 208a, 308a Opening 108b, 208b, 308b Step 109 HF Solution Circulation path 110 Electrolyte circulation path 111 Laminarized mesh 112 Wafer 208c Notch

Claims (4)

[Claims] 1. An opening formed in a flat plate-shaped member that can be attached to and detached from a wafer mounting portion of a semiconductor processing apparatus, the opening into which one surface side of a wafer to be processed is inserted, and the opening. A wafer transfer cassette having a support portion integrally provided on an inner wall of the opening for supporting an outer peripheral edge portion of the inserted wafer. 2. The wafer transfer apparatus according to claim 1, wherein the support portion is provided over the entire circumference of an inner wall of the opening, and a seal member is provided at a contact portion of the support portion with the wafer. cassette. 3. A part of a side wall of the flat plate-shaped member is
The wafer transfer cassette according to claim 1, wherein a notch reaching the opening is formed so that a wafer holding means for attaching and detaching the wafer to and from the opening can be passed. 4. A semiconductor processing apparatus in which a wafer mounting portion for mounting a wafer to be processed has a structure to which the wafer transfer cassette according to claim 1 can be attached / detached.