JPH09171997A - Dry etching apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a dry etching apparatus by which an etching treatment is performed uniformly by a method wherein a ring which is situated at the upper part from a wafer in a plasma and which is not situated directly above the wafer is installed so as not to come into contact width the wafer. SOLUTION: A wafer 13 is conveyed to the position of a wafer 13 inside a plasma treatment apparatus by means of a conveyance device. An insulating film 12 is formed between the wafer 13 and an electrode 10, a groove its formed on the insulating film 12, the groove is filled with a gas for wafer cooling, and the wafer 13 can be adjusted to a prescribed temperature. In addition, in order to protect the electrode 10 and the insulating film from a generated plasma, a ring 17 which is supported at a treatment-chamber wall 18 by a support 21 is installed on the whole circumference near the wafer 13. In this state, a DC bias voltage is applied to the electrode 10 by a DC power supply 11, the wafer 13 is attracted to the electrode 10 via the insulating film 12, a cooling gas is then introduced to the rear of the wafer 13, high-frequency power is applied to the electrode 10 by a high-frequency power supply 15, and the etching treatment of the wafer 13 is performed. Thereby, the etching treatment of the wafer can be performed with high uniformity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a dry etching apparatus, and more particularly to a dry etching apparatus having a ring installed near a wafer in plasma.

[0002]

2. Description of the Related Art In a conventional dry etching apparatus, no ring was provided near the wafer in the plasma so as not to come into contact with the wafer, and only etching with poor uniformity was obtained.

There is also a structure in which the wafer is in contact with plasma.

[0004]

In the conventional dry etching technique, no ring was installed in the vicinity of the wafer in the plasma so as not to come into contact with the wafer, and highly uniform etching treatment of the wafer was impossible.

An object of the present invention is to provide a highly uniform dry etching apparatus for a wafer by installing a ring having a structure in which the wafer does not come into contact with plasma.

[0006]

In order to achieve the above object, a ring having a structure that does not contact the wafer is installed in the plasma.

[0007]

1 and 2 show an embodiment of the present invention.
This will be described below. FIG. 1 is a schematic diagram of a plasma processing apparatus used in the present invention. In FIG. 1, in the plasma processing apparatus, the processing chamber 3 is isolated from the atmosphere by the quartz window 8 and the processing chamber wall 18. The processing chamber wall 18 is grounded. Further, the inside of the processing chamber 3 can be evacuated by the exhaust port 4, the pressure control valve 5, and the exhaust system 16, and the pressure inside the processing chamber 3 can be controlled to a predetermined pressure. A hollow portion 19 is installed inside the electrode 10, and the structure is such that the temperature of the electrode 10 can be adjusted by flowing a coolant whose temperature is adjusted by a temperature adjuster into the hollow portion 19.

In the above structure, the wafer 13 is transferred to the wafer 13 in the processing apparatus shown in FIG.
Is transported to the position. An insulating film 12 is provided between the wafer 13 and the electrode 10. The insulating film 12 has a groove, and by filling the groove with a gas for cooling the wafer, heat is exchanged between the wafer and the electrode, and the wafer can be adjusted to a predetermined temperature.

In order to protect the electrode 10 and its insulating film 12 from the generated plasma, a ring 17 supported by the support 21 on the processing chamber wall 18 is installed all around the wafer.

A DC power supply 11 is connected to the electrode 10 so that a DC voltage can be applied to the electrode. An AC power supply 15 is connected to the electrode 10 via a capacitor 20 so that an AC voltage can be applied.

Next, a gas for plasma generation whose flow rate is controlled by the gas flow rate control valve 2 is introduced into the processing chamber 3 from the gas introduction port 1 and is processed by the vacuum pump and the pressure adjusting valve 5 through the exhaust port 4. The pressure in the chamber 3 is adjusted to a predetermined pressure for plasma processing. In this state, the microwave generated by the microwave generator 6 is introduced into the processing chamber 3 through the microwave window 7 through the quartz window 8 and the coil 9
Electron cyclotron resonance is caused with the magnetic field generated by, and the gas for plasma generation is turned into plasma. In that state, a DC bias voltage is applied to the electrode 10 by the DC power supply 11 to generate an electrostatic attraction force between the wafer 13 and the electrode through the insulating film 12 to attract the wafer 13 to the electrode.

After that, a wafer cooling gas is introduced to the back surface of the wafer, and high-frequency power is applied to the electrodes by the high-frequency power source 15 to perform etching processing on the wafer. By the etching treatment, the etching uniformity could be improved from 22.8% (without ring) to 6.9% (with ring).

In this embodiment, the wall 21 of the processing chamber is supported by the support 21.
By installing the ring 17 supported by 8 around the entire circumference of the wafer, highly uniform etching of the wafer can be performed.

[0014]

According to the present invention, a ring that is not located above the wafer and directly above the wafer in the plasma is
Since the wafer is installed so as not to come into contact with the wafer, there is an effect that the wafer can be highly uniformly etched.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a plasma processing apparatus according to one embodiment of the present invention.

[Explanation of symbols]

1 ... Gas inlet, 2 ... Gas flow control valve, 3 ... Processing chamber, 4
... Exhaust port, 5 ... Pressure control valve, 6 ... Microwave generator, 7
... microwave waveguide, 8 ... quartz window, 9 ... coil (magnetic field generator), 10 ... electrode, 11 ... DC power supply, 12 ... insulating film,
13 ... Wafer, 14 ... Temperature controller, 15 ... AC power supply, 16 ...
Exhaust system, 17 ... Ring, 18 ... Processing chamber wall, 19 ... Cavity, 20 ... Capacitor, 21 ... Feed, 22 ... Electrode cover.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Motohiko Yoshikai 794 Azuma Higashitoyo, Shimomatsu City, Yamaguchi Prefecture Inside the Kasado Plant, Hitachi Techno Engineering Co., Ltd. No. 794 Stock company Hitachi Kasado factory

Claims (2)

[Claims] 1. A dry etching apparatus, characterized in that a ring which is not above the wafer and directly above the wafer in plasma is installed so as not to come into contact with the wafer to perform a highly uniform etching process. 2. The dry etching apparatus according to claim 1, wherein the electrode cover is protected from plasma by installing the ring.