JPS58153332A - Dry etching device - Google Patents

Abstract

PURPOSE:To prevent a resist for an etching mask from deteriorating and to etch it with good reproducibility at the desired velocity by individually controlling the temperatures of an etching base, a chamber container wall and upper electrode. CONSTITUTION:Constant-temperature insulating liquids which are controlled to the prescribed temperature values are supplied from individual constant-temperature tanks to cool by a cooler 9 an etching base 2, to prevent a resist film for etching the surface of a wafer 50 on the base, to respectively heat by heaters 11, 12 a chamber 4 and an upper electrode 5, thereby holding them at the temperature higher than the base 2, preventing the etching residues on the inner wall of the chamber and on the upper electrode surface from depositing, the residues are exhausted from a tube 8, thereby preventing the gas pressure in the container 4 from varying due to the evaporation of the volatile component from the residues, and the interior of the container is always set to the optimum gas pressure. As a result, desired etching velocity can be reproduced.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention discloses the method of manufacturing semiconductor wafers (hereinafter abbreviated as "wafers") by exposing them to a plasma of a fluorocarbon gas such as carbon tetrafluoride (CV4) or tricarbon hefluoride (C3Y8). The present invention relates to a dry etching device for etching.

FIG. 1 is a sectional view showing an example of a conventional dry etching apparatus.

In the figure, 11.1 is a base plate, and a portion of the surface of the +21 ti pace plate (1) is covered with an insulating plate (3) such as a tare plate.
(4) is an etching stage (4) fixed on the pace plate ill to form the lower electrode;
A cup-shaped chamber container (6) is placed to cover the chamber container (4) and the internal pressure etching stage (2), and is provided to face the chamber container (4) and the internal pressure etching stage (2) with a predetermined distance therebetween. The upper electrode (7) is held on the top plate of (4) via an insulator (6) such as Teflon.
is a gas introduction pipe which is fixed to the top plate of the chamber container (4) so as to pass through it, and is used to introduce a fluorocarbon gas such as OF4.03F8 into the chamber container (4), and (8) is one end thereof. A gas exhaust pipe is fixed at one end to the base plate 11) so as to pass through the base plate 11 and open inside the chamber container (4), and the other end is connected to an exhaust device (not shown). Although not shown, the etching stage (2) and the upper electrode (5) are connected to a high frequency power source.
Pass the gas introduction pipe (7) between the chamber container (4
) to generate plasma from the gas introduced into the chamber.

Next, the operation of this conventional example will be explained. First, a wafer (100) to be etched is placed on the surface of the etching stage (2). Next, the gas exhaust pipe (8
), while evacuating the inside of the chamber container (4), gas is introduced into the channel container (4) through the gas introduction pipe (7), and the gas pressure in the chamber container (4) is maintained at a predetermined value. Thereafter, when a high frequency power source is connected between the etching stage (2) and the upper electrode (6) to generate gas plasma, the way /\(100) is exposed to this gas plasma and etched. .

By the way, in this conventional device, Waeno (100
), the temperature of wafer 5 (100) rises, and the etching mask resist film (not shown) provided on the surface of wafer 5 (100) deteriorates, making precise selective etching difficult. There was no color.

In order to prevent this etching mask resist film from deteriorating, only the etching stage (2) is cooled, and a wafer (100) is placed on the surface of the cooled etching stage (2) in close contact therewith. K to cool
A device has been developed.

However, in an apparatus in which the etching stage is cooled, the etching residue generated when etching the wafer (100) with gas plasma is discharged through the gas exhaust pipe (8), and at the same time, the etching residue is discharged through the gas exhaust pipe (8). ) and on the surface of the upper electrode 161, and volatile components evaporate from the attached etching residue, and the gas pressure in the chamber container (4) fluctuates due to the evaporation of the volatile components. However, there is a drawback that it is not easy to obtain a desired etching rate for Waeno (100) using gas plasma with good reproducibility.

This invention was made in view of the above-mentioned drawbacks, and by making it possible to separately control the temperature of the etching stage, the container wall of the chamber container, and the upper electrode, It is an object of the present invention to provide a dry etching apparatus which can prevent deterioration of a resist film for an etching mask and can obtain a desired etching rate for a wafer with good reproducibility.

FIG. 2 is a sectional view showing a dry etching apparatus according to an embodiment of the present invention.

In the figure, the same reference numerals as in the conventional example shown in FIG. 1 indicate the same parts, and the explanation thereof will be omitted. (The etching stage (embedded inside the 91Fi etching stage (2)
2) an etching stage cooling pipe through which a low-temperature insulating liquid flows to cool the tto+t'r etching stage cooling pipe (9) and an insulator for insulating between the base plate (1), (Ill is a chamber a chamber heating tube buried inside the container wall of the chamber container (4) through which a high temperature insulating liquid flows for heating the container wall of the chamber container (4);
(I2) is buried inside the upper electrode (5) and the upper electrode (I2) is buried inside the upper electrode (5).
5) is an upper electrode heating tube through which a high temperature insulating liquid flows. Although not shown, the etching stage cooling pipe (9), the chamber heating pipe (river) and the upper electrode heating pipe (121) are each connected to separate thermostatic chambers whose temperature can be controlled, and within these thermostatic chambers, the respective predetermined temperatures are A constant-temperature insulating liquid whose temperature is controlled is passed through the etching stage cooling pipe (91), chamber heating pipe (11), and upper electrode heating pipe α to cool the etching stage (2) and the container wall of the chamber container (4). The temperature of the upper electrode (5) and the upper electrode (5) are controlled and maintained at the predetermined temperature.

In the apparatus of this embodiment, as shown in FIG. In step 4, the temperature of the stage (2) is set to a low temperature value to prevent deterioration of the etching resist film on the surface of the wafer (100) subjected to the etching stage (mounting process). The temperatures of the container wall and the upper electrode (Il) of the chamber container (4) are set to higher temperature values than the temperature of the etching stage (2), respectively, and the temperature of the inner wall surface of the chamber container (4) and the surface of the upper electrode (fit This etching residue can be discharged through the gas exhaust pipe (8) without adhering to the etching residue.Therefore, the gas pressure in the chamber vessel (4) is reduced by evaporation of volatile components from the etching residue. Because it does not fluctuate, the chamber container (4
) can be set to the optimum value to obtain a desired etching rate on the wafer (100) with good reproducibility.In this example, the etching stage (2).

Although a constant temperature insulating liquid controlled to a predetermined temperature value was used to control the temperature of the container wall and upper electrode (61) of the chamber container (4), it is not necessarily limited to a constant temperature insulating liquid. Other temperature control means that can control the temperature tubes of the etching stage (2), the container wall of the chamber container (4), and the upper electrode (61) separately may also be used.

As described above, in the dry etching apparatus of the present invention, separate temperature control means are provided for the etching stage, the container wall of the chamber container, and the upper electrode, respectively.
By using these temperature control means, the temperature of the etching stage is set to a low temperature value during etching, and the temperature of the container wall of the chamber/bar container and the above-mentioned upper electrode are respectively set to higher temperature values than the temperature of the etching stage. Preventing the etching resist film on the surface of the wafer placed on the etching stage from deteriorating and preventing etching residue from adhering to the inner wall surface of the chamber container and the surface of the upper electrode. This etching residue can be discharged. Therefore, the gas pressure in the chamber container does not fluctuate due to evaporation of volatile components from the etching residue, so the gas pressure in the chamber container can be set to an optimal value to achieve the desired etching rate for etching. can be obtained with good reproducibility.

[Brief explanation of drawings]

FIG. wJ1 is a sectional view showing an example of a conventional dry etching apparatus, and FIG. 2 is a sectional view showing an example of a dry etching apparatus of the present invention. In the figure, (11 is a pace plate, (2) is an etching stage, (3) is an insulating plate, (4) is a container,
(61 is the upper electrode, (71t1 gas inlet pipe, (81 is the gas exhaust pipe, (91 is the etching stage cooling pipe (temperature control means), (11) is the chamber heating pipe (temperature control means), (I21 is the upper electrode It is a heating tube (temperature control means). In addition, the same reference numerals in the figures indicate the same or equivalent parts. Agent: Shin Kuzuno - (1 other person) Procedural amendment (1 抛) June 19, 1980 1. Indication of the incident Tokugan Sho 6〒-3 Maro 66 No. 2
, Title of the invention Dry etching device 3, Person making the amendment 6, Detailed description of the invention in the specification to be amended, Figures 1 and 2 of the drawings 6, Contents of the amendment (1) Description of the specification Page 4, line 8, page 4, line 14, page 4, lines 17 to 18, page 4, line 18, page 4, line 19, row 5, line 5, page 5 Lines 8 to 9, page 5, number 15
Lines ~ 16, page 7, line 14, and page 8, line 5:
Wafer (100) J is replaced with wafer (50) J.
I am corrected. (2) Figures 1 and 2 of the drawings are corrected as shown in Figures 1 and 2 of the attached drawings, respectively. 7. One or more drawings showing Figures 1 and 2 after the revised list of attached documents

Claims (2)

[Claims] (1) A base plate, an etching stage fixed to a part of the surface of the base plate via an insulating plate and forming a lower electrode, and a channel (-) placed over the base plate to cover the etching stage. a container, an upper electrode provided in the chamber so as to face the etching stage at a predetermined distance, and held insulated on the container wall of the chamber container; A gas introduction pipe for introducing gas into the container, and a gas introduction pipe for introducing gas into the container; A semiconductor workpiece to be etched is placed on the surface of the etching stage, and while the inside of the chamber container is evacuated through the gas exhaust pipe, the chamber is removed through the gas introduction pipe. A gas is introduced into a container to generate plasma of the gas between the etching stage and the upper electrode, and the semiconductor wafer is exposed to the plasma of the gas for etching, the etching stage and the chamber container Separate temperature control means are provided for the chamber wall of the chamber vessel and the upper electrode, and these temperature control means set the temperature of the etching stage to a low temperature value during etching, and also control the temperature of the chamber wall of the chamber vessel and the upper electrode. A dry etching apparatus characterized in that each of the etching stages is set at a temperature higher than the temperature of the etching stage. (2) The dry etching apparatus according to claim 1, characterized in that the temperature control means uses a temperature-controlled, constant-temperature insulating liquid pipe.