JP2634795B2 - Wafer processing equipment - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for performing an etching process on a wafer in a wafer process which is a manufacturing process of a semiconductor device.

[Conventional technology]

2. Description of the Related Art Conventionally, in a wafer etching process, in particular, a process using a so-called chemical solution called a wet process, there are a number of processes for performing etching by a chemical action of similar or the same type of chemical solution. It was common to use

FIG. 2 shows the structure of a processing tank which is generally used in the prior art. The chemicals that contribute to the etching process are as shown in FIGS. 2 (a) and 2 (b). , A plurality of processing tanks 1, 4, and 5, each of which includes a processing tank 2 containing one type of etching chemical.
Alternatively, it possesses only one of the three types and is applicable only to a single processing step.

[Problems to be solved by the invention]

However, the degree of integration of semiconductor devices is rapidly increasing in density, and accordingly, the complexity of the wafer process, the number of steps, and the diameter of the wafer are inevitably increased. Accompanying this, various etching apparatuses used therein are required to be complicated, intelligent, and large in size, and the types and number of such apparatuses are steadily increasing. Increasing types and number of devices means that
The production cost is increased, the production time is prolonged, the floor space is enlarged, and the cost of maintaining and operating the clean room is increased.In addition, troubles caused by the newly designed equipment also increase. The time required for the restoration and the instability of the man-hours may cause a situation where it may be difficult to construct a stable production line.

Heretofore, it has been general to use a dedicated apparatus for certain etching conditions, that is, for a process in which the type of a chemical having an etching action, the temperature condition thereof, the etching time, and the like are determined. It is also common practice to use a dedicated device for the process, in which the temperature conditions or the etching time are different even if the chemical solutions used are similar or the same type, but different from those described above. .

The present invention provides a wafer processing apparatus capable of processing a plurality of etching steps in a single apparatus.

[Means for solving the problem]

A wafer processing apparatus according to the present invention is a wafer processing apparatus used in a wet etching step in a wafer process having a plurality of wet etching steps, wherein a common wafer processing apparatus is provided in a single apparatus main body for each of the plurality of wet etching steps. When the first wet etching step is performed by providing a common processing tank to be used as the first and second wet etching steps, and first and second processing tanks required independently for each of the first and second wet etching steps Performing the wet etching using the first and the common processing tanks without using the second processing tank, and using the first processing tank when performing the second wet etching step. The wet etching is performed using the second and common processing tanks without performing.

〔Example〕

 Hereinafter, an embodiment of the present invention will be described.

Among the wet processes in the wafer process, a general etching process includes an oxide film etching process. The process of etching an oxide film to form a pattern on one wafer is a total of 10 to 20 times, and the chemical used for each is a so-called buffered hydrofluoric acid in which hydrofluoric acid and ammonium fluoride are mixed at a certain ratio. (Hereinafter referred to as BHF), and generally two types are used in each step depending on the mixing ratio.

Further, in order to make it possible to carry out the etching action efficiently and uniformly, it is common practice to make the etching contact with the activating liquid immediately before the contact with the etching liquid.

FIG. 1 shows a configuration of a processing phase which is a part directly related to the present invention. The apparatus of the present invention has a plurality of processing tanks 1 to 5, and an activating liquid (hereinafter referred to as “A”) is provided in the first layer 1.
, And then “BHF-1” in the second layer 2 and the third tank 3
Contains "BHF-2" (BHF having a different mixing ratio from BHF-1). The fourth tank 5 and the fifth tank 5 are, for example, washing tanks containing pure water (hereinafter referred to as “D-1” and “D-2”, respectively). Here, the first tank 1, the fourth tank 4, and the fifth tank 5 constitute a first specification section, which is a set of etching-only equipment commonly used for each etching process in the wafer process. . In this apparatus, since the processing tanks 2 and 3 for etching BHF-1 and BHF-2 having different mixing ratios are included as constituent elements, it is possible to selectively process different oxide film etching steps. It is possible. Here, at least two types of etching-dedicated equipment that are individually accommodated in etching chemicals having different mixing ratios used in the respective etching processing steps by the combination of the etching processing tanks 2 and 3 and are selectively used in the respective etching processing steps. A second specification unit is configured. In the process to be subjected to the etching treatment using BHF-1, by keeping the temperature condition constant, "A → BHF-1 → D
-1 → D-2 "can be performed.
Similarly, in the process of performing the etching process using -2, the process of "A → BHF-2 → D-1 → D-2" can be performed in a single apparatus. A, BHF-1, BHF-2, D
The processing time in -1, D-2 can be arbitrarily selected and input, so that the set time can be realized.

The sequence is further extended to "A → BHF-1 → D
-1 → BHF-1 → D-2 "or“ A → BHF-2 → D-1
It is also possible to perform the processing of "→ BHF-2 → D-2".

Further, A is omitted or D-1 or D-2.
By executing a sequence such as omitting a number of steps, many steps can be performed in a single device.

〔The invention's effect〕

As described above, according to the present invention, the functions required in a plurality of processes can be selected as required by having a specification section common to each etching-dedicated equipment and a specification required individually. , Can be processed.

According to the present invention, the types and number of devices required in the wet etching process can be greatly reduced, and the manufacturing cost of the devices can be reduced, the manufacturing period can be shortened, the floor space can be reduced, and a clean room can be maintained. The economic effects such as the reduction of operating costs will be great.

[Brief description of the drawings]

FIG. 1 is a view showing a configuration of a processing tank according to an embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are views showing a configuration of a conventional processing tank. 1 1st tank 2 2nd tank 3 3rd tank 4 4th tank 5 5th tank

Claims (1)

(57) [Claims] 1. A wafer processing apparatus used in a wet etching step in a wafer process having a plurality of wet etching steps, wherein the wafer processing apparatus is commonly used in each of the plurality of wet etching steps in a single apparatus main body. And a first processing tank and a first processing tank, which are individually required for each of the first and second wet etching steps, are provided when performing the first wet etching step. Performing wet etching using the first and common processing tanks without using the second processing tank, and without using the first processing tank when performing the second wet etching step. A wafer processing apparatus for performing wet etching using the second and the common processing tanks.