JPH0448626A - Dry etching apparatus - Google Patents

Abstract

PURPOSE:To greatly shorten a time of wafer cooling vacuum evacuation in a later processing sequence and to largely improve throughput of an etching process by providing temperature raising means for previously heating a semiconductor wafer in a preliminary chamber or a wafer buffer layer, and cooling means for similarly cooling it. CONSTITUTION:A semiconductor wafer 4 is placed on a preliminary stage 19 before the wafer 4 is conveyed into a processing chamber l, the wafer 4 is first heated, moisture, etc., adhered onto the wafer 4 is outgassed, and the wafer 4 is then cooled to a predetermined value. The heating, cooling are conducted while the wafer 4 is etched in the chamber l, and conveyed to the chamber l when the process is ended. Then, a processing sequence is started, and since the outgassing and the cooling are conducted previously, a time to reach predetermined vacuum degree and temperature is largely shortened.

Description

[Detailed Description of the Invention] [Industrial Application Field] The invention of Part B relates to a dry etching apparatus for performing dry processing on a semiconductor wafer in a semiconductor wafer process.

[Conventional technology]

FIG. 2 shows a schematic diagram of a conventional dry etching apparatus of this type. In this figure, reference numeral 1 denotes a processing chamber, which is configured to be airtight, and a vacuum pump (not shown) is connected to an exhaust path 2 provided at the bottom of the chamber to evacuate the chamber.

A stage 3 is arranged in the processing chamber 1 and holds a semiconductor wafer 4 thereon, and a cooler 5 for cooling the semiconductor wafer 4 is connected thereto. Furthermore, a gas introduction #56 is provided at the upper part of the processing chamber 1 for introducing processing gas into the chamber. Reference numeral 7 denotes a liquid guiding pipe provided in the upper part of the processing chamber 1 through a quartz window 8, to which a microwave generator 9 is connected and applies microwaves to the inside of the processing chamber 1. 10 is a coil provided outside the processing chamber 1, and the stage 3
The magnetic field is designed to be generated in a direction perpendicular to the surface of the semiconductor wafer 4 placed on the substrate. A preliminary chamber 11 is adjacent to the processing chamber 1 via a vacuum opening/closing means 12. Reference numeral 13 denotes a wafer buffer chamber, which is adjacent to the preparatory chamber 11 via a vacuum opening/closing means 14, in which a cassette 1 for storing semiconductor wafers 4 is placed.
5 is accommodated. Reference numeral 16 denotes a wafer transport means for transporting the semiconductor wafer 4 between the wafer buffer chamber 13 and the processing chamber 1.
transportation.

Next, the operation will be explained.

The cassette 15 containing the semiconductor wafer 4 is stored in the wafer buffer chamber 13, and when the evacuation is completed, the vacuum opening/closing means 12 and the vacuum opening/closing means 14 are opened, and the semiconductor wafer 4 is transferred from the wafer buffer chamber 13 to the processing chamber 1. Means 16
When the vacuum opening/closing means 12 is closed, a series of processing sequences are started.

First, a desired vacuum evacuation is performed, and at the same time, the semiconductor wafer 4 is cooled. When the respective desired values are reached, the gas introduction path 6
A predetermined gas is introduced, and when a predetermined pressure is reached, a magnetic field and microwaves are applied to generate plasma and perform etching processing. The vacuum evacuation and wafer cooling described above are
CR (Electron Cyclotron etc.
hing) principle is an important factor in etching processing, and the purpose of vacuum evacuation is to remove impurities in the processing chamber 1 before introducing the processing gas.
Evacuate to about 1X10-' to 10-6 Torr. Further, wafer cooling is necessary in order to etch the etching target [18] according to the dimensions of the mask 17 as shown in FIG. 3(a), and if cooling is not performed,
). The cooling temperature varies depending on the processing gas used, but is usually about 0°C to -several tens of degrees Celsius. However, as in the configuration shown in FIG. 2, when the semiconductor wafer 4 is cooled from room temperature, for example to about 30° C., it takes about 1 minute. In addition, in order to cool the semiconductor sea urchin, remove moisture etc.
The gas becomes weak and the desired degree of vacuum is I x 10'-
There was a problem in that it took several minutes to evacuate to 10-10 Torr.

[Problem to be solved by the invention]

As mentioned above, in the conventional dry etching apparatus, the semiconductor wafer 4 is cooled from room temperature to a few tens of degrees Celsius on the stage 3 in the processing chamber 1, so it takes time to complete cooling, and This makes it difficult for outgases such as filtrate water to adhere to the semiconductor substrate 4, and to reduce the temperature at a predetermined degree of vacuum from 1.0-' to 10-'T.
It takes several minutes to evacuate to orr, which poses a problem in that the throughput during the etching process is significantly reduced.

This invention was made in order to solve the above-mentioned problems, and by cooling the semiconductor wafer 1 with a gas such as moisture in advance, it is possible to speed up the processing in the processing chamber. The object of the present invention is to obtain a dry etching device with a high temperature.

[Means to solve the problem]

The dry etching apparatus according to the present invention is provided with a temperature raising means for raising the temperature of the semiconductor urchin/'1 in the preliminary chamber or the wafer buffer chamber, and a cooling means for cooling the same. It is.

[Effect]

In the dry etching apparatus of the present invention, outgas such as moisture adhering to the semiconductor urchin/4 is removed in advance in the preliminary chamber or wafer buffer chamber before being transported into the processing chamber, and then the semiconductor wafer is cooled before being transported into the processing chamber. Therefore, the cooling time in the processing chamber to reach the desired cooling temperature and the evacuation time to reach the desired degree of vacuum can be greatly shortened.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.

FIG. 1 is a schematic diagram of a dry etching apparatus showing an embodiment of the present invention. In this figure, 1 to 16 indicate the same parts as in FIG. 2. Reference numeral 19 denotes a preliminary stage provided in the preliminary chamber 11, to which a heating machine 20 capable of raising the temperature of the semiconductor wafer 4 to about 100 degrees Celsius and a cooler 21 capable of cooling it down to -several tens of degrees Celsius are connected. There is.

Now, in the embodiment of the present invention configured in this way, the semiconductor wafer 4 is placed on the preliminary stage 19 before being transported into the processing chamber 1, and the temperature of the semiconductor wafer 4 is first raised. The semiconductor wafer 4 is then cooled down to a desired temperature. This heating and cooling is performed while the previous semiconductor wafer 4 is undergoing etching processing in the processing chamber 1, and is transferred to the processing chamber 1 upon completion of the processing. After this,
The same processing sequence as before is started, but since outgassing and cooling have been performed in advance, the time it takes to reach the predetermined degree of vacuum and temperature is significantly shortened.

In the above embodiment, outgassing and cooling of the semiconductor wafer 4 due to temperature rise were performed in the preliminary chamber 11.
It may also be carried out within the wafer buffer chamber 13, and the same effects as in the above embodiment can be achieved.

〔Effect of the invention〕

As explained above, in the present invention, the preparatory chamber or the wafer buffer chamber is provided with a temperature raising means for warming the semiconductor wafer in the preparatory chamber or the wafer buffer chamber, and a cooling means for cooling the semiconductor wafer in the same manner. This method has extremely excellent features in that the time required for wafer cooling and vacuum evacuation in the subsequent processing sequence can be significantly shortened, and the throughput in etching processing can be greatly improved.

[Brief explanation of drawings]

FIG. 1 is a schematic block diagram of a dry etching apparatus showing an embodiment of the present invention, FIG. 2 is a schematic block diagram of the dry etching apparatus shown in FIG. 2, and FIG. 3 is a diagram showing a cross section of a wafer after etching processing. In the figure, 1 is a processing chamber, 2 is an exhaust path, 3 is a stage,
4 is a semiconductor wafer, 5 is a cooler, 6 is a gas introduction path, 7 is a waveguide, 8 is a quartz window, 9 is a microwave generator, 10 is a coil, 11 is a preliminary chamber, 12 is a vacuum opening/closing means, 13 14 is a wafer buffer chamber, 14 is a vacuum opening/closing means, 15 is a cassette, 16 is a wafer transfer means, 19 is a preliminary stage, 2o is a temperature riser, and 21 is a cooler. Note that the same reference numerals in each figure indicate the same or corresponding parts. Agent Masuo Oiwa (2 others) Figure 1 Figure 2 (a) (b) ]○ Coil

Claims (1)

[Claims] a processing chamber in which a processing gas is turned into plasma by a magnetic field and an electric field generated by microwaves to perform dry processing on semiconductor wafers; a preliminary chamber provided in the processing chamber via a vacuum opening/closing means;
In a dry etching apparatus comprising a wafer buffer chamber provided in the preliminary chamber via a vacuum opening/closing means, the semiconductor wafer is heated in advance in the preliminary chamber or wafer buffer chamber. A dry etching apparatus characterized in that it is equipped with a means for raising the temperature and a means for cooling the same.