JPH08130100A - Electrode structure of plasma treatment apparatus - Google Patents

Abstract

PURPOSE: To lower the manufacturing cost and at the same time lower the running cost necessary to change consumed parts by separating a sample stand and a d.c. electrode, regarding an electrode of a plasma treatment apparatus. CONSTITUTION: An electrode 10 for static electricity adsorption is installed on the opposite to an opposed electrode 6, a d.c. power source 12 is connected with the electrode 10 for static electricity adsorption, and a sample stand 17 made of an insulating material is installed so as to be brought into contact with the opposed side of the electrode 10 for static electricity adsorption to the opposed electrode 6. In the case plasma is generated in condition that a d.c. electric field is applied to the electrode for static electricity adsorption, charged electrons from the plasma impinge upon a sample to charge the sample and the sample is attracted and closely attached to a high frequency electrode.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrode structure of a plasma processing apparatus provided in a semiconductor manufacturing apparatus such as a plasma etching apparatus, a sputtering apparatus and a CVD apparatus.

[0002]

2. Description of the Related Art FIG. 2 shows a method of etching, sputtering, CVD (Chemical Vapor) using plasma.
It is sectional drawing of the semiconductor manufacturing apparatus which performs wafer processings, such as a por deposition process.

A high frequency electrode 3 is provided at the bottom of an airtight reaction chamber container 1 via an insulating block 2.
A sample table 4 is disposed on the top of the sample table 4. The sample table 4 is fixed at its periphery by a sample table retainer 5 made of an insulating material so that the sample receiving surface is exposed. A counter electrode 6 facing the high-frequency electrode 3 is provided on the ceiling surface of the reaction chamber container 1, and a reaction gas introduction line 7 communicates with the inside of the reaction chamber container 1.

A liquid circulation path 8 is formed in the high-frequency electrode 3, and a heated or cooled liquid is circulated in the liquid circulation path 8 to heat or cool the wafer 9 through the sample stage 4. It has a structure.

An electrostatic attraction electrode 10 is embedded in the sample table 4 in parallel with the sample receiving surface, and the electrostatic attraction electrode 10 is connected to a DC power source 12 via a low-pass filter 11 composed of a coil and a capacitor. It is connected. The high frequency electrode 3
Is connected to a high-frequency power source 14 via a matching unit 13, and the high-frequency electrode 3 and the electrostatic attraction electrode 10 are connected by a capacitor 15 so that they have the same potential.

The sample stage 4 of the reaction chamber container 1 is in a depressurized state by exhausting the inside of the reaction chamber container 1 with a pump (not shown).
The wafer 9 is placed on the wafer by a carrier (not shown). Next, the low-pass filter 1 is attached to the electrostatic attraction electrode 10.
A DC electric field is applied by the DC power source 12 via 1,
The reaction gas is introduced through the reaction gas introduction line 7 into the reaction chamber container 1
Introduce inside. At the same time, after the pressure inside the reaction chamber container 1 is set to a predetermined value by a pressure control device (not shown), high frequency power is applied to the high frequency electrode 3 from the high frequency power source 14 via the matching unit 13. The reaction gas is turned into plasma and the wafer 9 is processed.

Since the capacitor 15 makes the high frequency electrode 3 and the electrostatic attraction electrode 10 have the same potential, the high frequency electrode 3 and the electrostatic attraction electrode 10 when the high frequency power is applied to the high frequency electrode 3. Suppresses the dielectric loss in the insulating member between.

When plasma is generated, charged particles are incident on the wafer 9 on the sample table 4 from the plasma, the wafer 9 is charged, and is strongly attracted to the sample table 4 by electrostatic force. The heat exchange efficiency between 4 is increased.

[0009]

In the above-mentioned conventional wafer suction apparatus, the sample holder 4 is fixed so that the wafer mounting surface of the sample holder 4 is exposed. Therefore, the peripheral portion of the wafer mounting surface of the sample table 4 is exposed while the wafer is mounted, and the peripheral portion is exposed to the plasma, and the peripheral portion is damaged by the plasma, or the dielectric characteristics are affected by the high frequency electric field. Sample table 4 at an appropriate time because
Must be replaced.

However, in the above-mentioned conventional example, since the electrostatic attraction electrode 10 is embedded in the sample table 4, the sample table 4 is further manufactured by a method such as sintering, and the sample table 4 itself is expensive. Therefore, it is uneconomical to replace all of the sample table 4 including the electrostatic attraction electrode 10 as a consumable item. Further, the work such as the attachment / detachment of wiring to / from the electrostatic attraction electrode 10 has been complicated.

In view of such circumstances, the present invention intends to reduce the manufacturing cost, facilitate the replacement of consumables, and reduce the running cost by adopting a structure in which the sample stage and the DC electrode are separated. is there.

[0012]

SUMMARY OF THE INVENTION According to the present invention, an electrostatic attraction electrode is provided so as to face a counter electrode, a DC power source is connected to the electrostatic attraction electrode, and the electrostatic attraction electrode is opposed to the opposite electrode. The present invention relates to an electrode structure of a plasma processing apparatus in which a sample base made of an insulating material is provided in contact with a surface facing an electrode and a high frequency power source is connected to an electrostatic attraction electrode.

[0013]

When plasma is generated with a DC electric field applied to the electrostatic attraction electrode, the sample is charged by the valence electrons entering the sample, and the sample is attracted and adhered to the electrostatic attraction electrode.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, the same components as those shown in FIG. 2 are designated by the same reference numerals.

Electrode 10 for electrostatic adsorption which doubles as high frequency electrode 3 with insulating block 2 at the bottom of airtight reaction chamber container 1.
Is provided, and a sample table 17 that covers the electrostatic attraction electrode 10 and the upper surfaces of the insulating block 2 is provided on the electrostatic attraction electrode 10.
Is attached to the electrostatic attraction electrode 10 so as to be detachable. The sample table 17 is made of an insulating material and has a thickness of usually 0.3 to 2 mm, or 2 mm or more depending on conditions. A counter electrode 6 is provided on the ceiling surface of the reaction chamber container 1 so as to face the sample table 17.

A reaction gas introducing line 7 communicates with the inside of the reaction chamber container 1. A liquid circulation path 8 is formed in the electrostatic attraction electrode 10, and a heated or cooled liquid is circulated in the liquid circulation path 8 to heat or cool the wafer 9 through the sample stage 17. It has a structure that

A DC power source 12 is connected to the electrostatic attraction electrode 10 via a low-pass filter 11 composed of a coil and a capacitor, and the electrostatic attraction electrode 10 is matched by a matching unit 1.
It is connected to the high frequency power supply 14 via 3.

The operation will be described below.

The sample stage 1 of the reaction chamber container 1 is in a depressurized state by exhausting the inside of the reaction chamber container 1 with a pump (not shown).
The wafer 9 is mounted on the wafer 7 by a carrier (not shown). Next, the low-pass filter 1 is attached to the electrostatic attraction electrode 10.
A DC electric field is applied by the DC power source 12 via 1,
The reaction gas is introduced through the reaction gas introduction line 7 into the reaction chamber container 1
Introduce inside. At the same time, after the pressure inside the reaction chamber container 1 is set to a predetermined value by a pressure control device (not shown), a high frequency power source 14 is applied to the electrostatic attraction electrode 10 via the matching unit 13.
When more high frequency power is applied, the counter electrode 6 and the sample table 1
Plasma is generated during 7.

When plasma is generated, charged particles enter the wafer 9 on the sample table 17 from the plasma,
The wafer 9 is charged and strongly attracted to the sample table 17 by the electrostatic force, and the heat exchange efficiency between the wafer 9 and the sample table 17 is increased.

Thus, the sample table 17 is completely separated from the electrostatic attraction electrode 10 which also serves as the high frequency electrode 3, and the sample table 1 is further separated.
Reference numeral 7 serves as a protective cover for the electrostatic attraction electrode 10 and the insulating block 2. When the sample table 17 is worn or the material is deteriorated and is to be replaced, the sample table 17 is detachable from the electrostatic attraction electrode 10, and therefore the sample table 17 is replaced independently. Furthermore, there is no electrical connection to the sample table 17,
Exchange work is easy.

Needless to say, the sample is not limited to a wafer and may be a sample such as a glass substrate.

Further, in the above embodiment, the electrostatic attraction electrode 10 is used.
The high-frequency electrode 3 and the high-frequency electrode 3 are also used, but both electrodes are separately provided, and the electrostatic attraction electrode 10 is separated from the sample stage 17 so that the sample stage 17 is provided in contact with the upper surface of the electrostatic attraction electrode 10. May be.

[0025]

As described above, according to the present invention, since the sample table is separated from the electrostatic attraction electrode to form a single component, it is possible to easily replace the sample table and reduce the manufacturing cost of the sample table. In addition, the running cost of the device can be reduced, and since the electrostatic attraction electrode and the high frequency electrode are integrated, the sample stand holder, the capacitor or the parts related to them are reduced, the configuration is simplified and the cost is reduced. It has an excellent effect that it can be reduced.

[Brief description of drawings]

FIG. 1 is a schematic sectional view showing an embodiment of the present invention.

FIG. 2 is a schematic sectional view showing a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reaction chamber container 2 Insulation block 3 High frequency electrode 6 Counter electrode 7 Reactive gas introduction line 9 Wafer 11 Low pass filter 12 DC power supply 13 Matching device 14 High frequency power supply 17 Sample stage

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display location H01L 21/3065 21/68 R

Claims (2)

[Claims] 1. An electrostatic attraction electrode is provided so as to face a counter electrode, a DC power source is connected to the electrostatic attraction electrode, and the electrostatic attraction electrode is in contact with a surface of the electrostatic attraction electrode facing the counter electrode. An electrode structure of a plasma processing apparatus, which is provided with a sample base made of an insulating material. 2. The electrode structure of the plasma processing apparatus according to claim 1, wherein a high frequency power source is connected to the electrostatic attraction electrode.