JPH1154475A - Wet etching device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact device which hardly breaks down by simplifying a mechanism of a multifunctional wet etching device on a single-wafer basis and reducing mixing in each chemical collection. SOLUTION: In a basic etching device, an etching chamber division mechanism part is constituted by opening and closing movable plates 7a, 7b, without vertically moving a rotary mechanism 4 of a sample and a chemical supply nozzle 5, and the chemical is exclusively collected corresponding thereto. In other basic etching devices, chemical after the etching treatment, is collected selectively by a special collection opening using gravity, and either depressurization and pressurization. Thereby, it is possible to constitute a multifunctional wet etching device through a simple mechanism and to realize compactness and low cost. Since the etching liquid collection method of a device is simple and etching liquid hardly mixes, troubles are reduced and maintenance of the chemical to be used by circulating and a device is facilitated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0101]

The present invention relates to a single wafer type wet etching apparatus.

[0092]

2. Description of the Related Art As a technique for forming a fine element by precision processing, a wet etching technique is still widely used in a manufacturing process. Normal wet etching is a simple method in which a sample is immersed in a chemical solution, then removed, washed, and dried.However, it is used exclusively for processing the entire sample with high accuracy and processing between samples with high reproducibility. A designed wet etching apparatus is required. The use of this apparatus is also expected to save labor in the etching step and improve productivity. There are many wet etching processes in the manufacturing process of a semiconductor device such as a Si LSI, and a wet etching apparatus is used in a part. For a sample of a fixed size such as a Si wafer, a batch type apparatus for processing a plurality of substrates by one etching and a single-wafer type apparatus for processing one substrate at a time are manufactured. The single-wafer apparatus has (1) good in-plane processing dimensional accuracy for a large sample,
(2) Economical use of etchant circulation system, (3)
The sample can be washed and dried in the same device, and it is easy to automate. In addition, the single-wafer etching apparatus has a feature that a process for continuously processing the sample surface with two or more types of chemicals can be constructed, and the process can be multifunctional. FIG.
Is a device devised for performing continuous processing on one sample 72 using two kinds of chemicals. The sample 72 is held by the rotation mechanism 74, and a chemical solution is supplied from the nozzle 75 while rotating the sample, and wet etching is performed. The nozzle 75, the sample 72, and the rotation mechanism 74 are integrally moved up and down 100 and 101, respectively, in an elevator manner, so that the sample 72 stops at the partitions 77, 78, and 79 of the respective etching chambers. The stop position is determined for each type of chemical solution, and in this case, two types of treatments for the chemical solution and pure water cleaning can be performed.
The chemical waste liquid dedicated to each etching chamber has its own drain 7
It is recovered from 7d, 78d, 79d and avoids mixing with each other.

[0093]

The conventional elevator-type device has a complicated mechanism because the rotating mechanism of the sample and the nozzle for supplying the chemical solution need to be moved up and down. Each etching chamber has a structure in which a chemical solution easily leaks. As a result, there is a problem that the apparatus becomes large and the chemical used for circulation does not have a long time. The present invention is based on etching a sample in a multifunctional single-wafer type etching apparatus using two or more types of etching solutions while fixing a sample rotation mechanism and a chemical solution supply nozzle, thereby miniaturizing the apparatus, An object is to provide a device that can operate stably for a long period of time. It is another object of the present invention to provide a device that has a configuration in which individual chemical solutions are hardly mixed and that has a long-term use of a chemical solution to be used in circulation.

[0093]

As shown in FIG. 1, the etching apparatus on which the present invention is based does not move the sample rotation mechanism 4 and the chemical solution supply nozzle 5 up and down, but instead moves the etching chamber dividing mechanism to the movable plate 7a. , 7b, and has a mechanism for collecting a chemical solution exclusively for each etching process. Further, another basic etching apparatus according to the present invention is characterized in that it has a mechanism for selectively introducing a chemical solution after the etching process to a dedicated recovery port using one of gravity, reduced pressure, and increased pressure. I have.

[0056]

BEST MODE FOR CARRYING OUT THE INVENTION

Embodiment 1 FIG. 1 shows an embodiment of a wet etching apparatus 1 according to the present invention. A semiconductor crystal wafer 2 which is a material to be wet-etched is fixed to a rotary holder 3. This fixing method is performed by a mechanical method, a vacuum method, or the like. The rotation mechanism 4 can change the range of the rotation holder 3 from low speed to high speed at an arbitrary rotation speed. The rotation speed is generally low during wet etching and high during drying of the sample. In processing the sample, an arbitrary chemical is supplied from the chemical supply nozzle 5 onto the semiconductor crystal wafer 2. Here, a dedicated nozzle for each chemical is bundled to form a chemical supply nozzle 5. Further, a nozzle for pure water for cleaning and a nozzle for nitrogen gas for drying are also arranged at substantially the same positions, but are omitted in this figure. In the example of FIG. 1, the etching liquid recovery chambers 7, 8, and 9 corresponding to three types of chemicals are movable plates 7a-7b, respectively.
8a-8b, 9a-9b and rotating shaft collars 7c, 8c, 9c
It is shown that it is constituted by. This etching liquid recovery mechanism is provided with a predetermined movable plate 7a corresponding to the used chemical liquid # 1.
-7b is protruded toward the vicinity of the rotating shaft collar 7c of the rotating mechanism 4. The same applies to the case of using the chemicals # 2 and # 3. The used etchant is returned to the circulation system of each chemical from the recovery ports 7d, 8d, and 9d for each chemical. The pure water for washing flows to the drain 10d. There are shutter plates 7s, 8s, 9s and 7s', 8s', 9s' in order to avoid mixing between the collected chemicals and pure water for cleaning. Sample etching is performed according to a predetermined sequence.
For example, the treatment is performed in the order of the chemical solution # 1, the chemical solution # 2, and the chemical solution # 3, and after each chemical solution treatment, a pure water washing and drying process is performed. 3 and 4 show configuration examples of the movable plate of the present invention. FIG. 3 shows the configuration of the etching liquid collecting plate connected to the vicinity of the rotating shaft 39 by sliding the two movable plates 31 and 32 by an upper surface (a) and a cross section (b). The hole 38 of the connecting plate is provided to avoid contact with the rotating shaft 39. FIG. 4 shows six rotating plates 41 ′,
This is an example in which an etchant recovery plate is formed in the vicinity of the sample rotation shaft 49 using 42 ′, 43 ′, 44 ′, 45 ′, and 46 ′. At the time of etching solution recovery, each rotating plate rotates around the axis z toward the sample rotation axis 49 to form the etching solution recovery plates 41, 42, 43, 44, 45, and 46 without gaps. In the case of a recovery plate using a rotating plate, it is effective to reduce the size of the apparatus, and the number and shape are not limited to the example of FIG.

Embodiment 2 FIG. 2 shows another embodiment of the wet etching apparatus 21 according to the present invention. The etching liquid collecting method corresponding to the three kinds of etching liquids is the same as the basic structure described in the first embodiment, but the movable plates 27a-27b, 28a-28b, 29a-
An example in which the structure of 29b is different will be described. The movable plate according to the present invention is constituted by, for example, the rotating plate shown in FIG. When collecting the respective etching liquids, the rotating plates rotate inward and combine to form a receiving plate. If the receiving plate is placed at an angle from the horizontal as shown in FIG. 2, the recovery of the etching solution is completed.

Embodiment 3 Another embodiment of the wet etching apparatus 51 according to the present invention will be described. FIG. 5 is a conceptual diagram of the apparatus as viewed from the side, which is characterized by the arrangement of the inclined sample. Semiconductor crystal wafer 5
2 is fixed to the rotation holder 53, and the inclined rotation mechanism 54
Make any rotation by. A predetermined chemical solution is supplied from the chemical solution supply nozzle 55 to the surface of the semiconductor crystal wafer 52, and is etched while rotating the sample. The etchant is collected at a predetermined recovery port. Unused collection ports are closed with shutters. In this embodiment, the etchant is selectively introduced into a dedicated recovery port by using gravity and any one of pressure reduction and pressure. Although the drain port for pure water for cleaning is omitted in the figure, it is the same as the treatment of the recovery port for the etching solution. According to this configuration, there are few movable parts for recovery, so that it is hard to break down, and it is easier to reduce the size of the apparatus.

Embodiment 4 FIG. 6 shows another embodiment of the wet etching apparatus 61 according to the present invention. As shown in the third embodiment, the surface of the semiconductor crystal wafer 62 is etched by another kind of chemical by the inclined rotating mechanism 64. As the chemical solution supply nozzle 65, a band-shaped mouth is used as shown in the figure. As a result, a laminar etching solution is supplied, and the in-plane uniformity of processing is improved. A predetermined recovery port 67d for a predetermined chemical solution is arranged at the lower part of the apparatus. This is to collect the etching solution by gravity. When using the recovery port 68d and the recovery port 69d as shown in the figure, these are rotated to r1 and r2, respectively, and arranged at predetermined positions. The same applies to the drain port of pure water after washing. According to this configuration, mixing of the liquids due to the collection does not occur.

[0099]

【The invention's effect】

(1) The multifunctional wet etching apparatus can be reduced in size. (2) In this apparatus, it is not necessary to move the rotating mechanism up and down, so that the cost can be reduced. (3) Since the etching liquid recovery system of the present apparatus has a simple structure, it has few failures and is easy to maintain. (4) The etching liquid is not easily mixed with the etching liquid recovery system of the present apparatus.

[Brief description of the drawings]

FIG. 1 is a main configuration diagram of a multifunctional wet etching apparatus according to a first embodiment of the present invention.

FIG. 2 is a main configuration diagram of a multifunctional wet etching apparatus according to a second embodiment of the present invention.

FIG. 3 is a configuration diagram of an etching solution collecting plate connected by a movable plate used in Examples 1 and 2 of the present invention.

FIG. 4 is a configuration diagram of an etching solution recovery plate constituted by a rotating plate used in Embodiments 1 and 2 of the present invention.

FIG. 5 is a main configuration diagram of a multifunctional wet etching apparatus according to a third embodiment of the present invention.

FIG. 6 is a main configuration diagram of a multifunctional wet etching apparatus according to a fourth embodiment of the present invention.

FIG. 7 is a main configuration diagram of a conventional multifunctional wet etching apparatus.

[Explanation of symbols]

1, 21, 51, 61, 71: wet etching apparatus 2, 22, 52, 62, 72: sample 3, 23, 53, 63, 73: rotation holder 4, 24, 54, 64, 74: rotation mechanism section 5 , 25, 55, 65, 75... Chemical solution supply nozzles 7a-7b, 8a-8b, 9a-9b, 27a-27
b, 28a-28b, 29a-29b, 31, 32 ... movable plate 41, 41 ', 42, 42', 43, 43 ', 44, 4
4 ', 45, 45', 46, 46 '... Rotating plate 7d, 8d, 9d, 27d, 28d, 29d, 57d,
58d, 59d, 67d, 68d, 69d ... collection ports.

Claims (4)

[Claims] In a wet etching apparatus for processing a sample surface with a chemical solution, a collection partition region is formed by a movable plate so that two or more types of chemical solutions and a chemical solution and cleaning water are not mixed in the recovery of each of the chemical solutions. Wet etching equipment characterized by the following. 2. The wet etching apparatus according to claim 1, wherein the movable plate is a rotating plate composed of a large number of rotating plates, and the rotation of the movable plate constitutes a collecting section area. 3. A wet etching apparatus for processing a sample surface with a chemical solution, comprising a rotating mechanism portion inclined so that two or more types of chemical solutions and the chemical solution and the washing water are not mixed in the recovery of each of the chemical solutions. And a wet etching apparatus characterized in that it is selectively introduced into a dedicated recovery port by using any one of pressure reduction and pressure. 4. A wet etching apparatus for processing a sample surface with a chemical solution, comprising a rotary mechanism that is inclined so that two or more types of chemical solutions and a chemical solution and cleaning water do not mix in the recovery of each of the chemical solutions. Wet characterized by having a configuration in which the dedicated collection port is rotated and arranged at the lower part of the device in accordance with the type of the chemical solution to selectively introduce it into the dedicated collection port using the force of Etching equipment.