Plasma treatment device

• US 6,245,202 B1
• Filed: 10/08/1998
• Issued: 06/12/2001
• Est. Priority Date: 04/12/1996
• Status: Expired due to Term

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: Edamura, Manabu, Yoshioka, Ken, Nishio, Ryoji, Kanai, Saburo
• Primary Examiner(s): Nguyen, Nam
• Assistant Examiner(s): VerSteeg, Steven H.
• Application Number:
  US09/155,906
• Time in Patent Office: 978 Days
• Field of Search: 204/288.06, 204/298.09, 204/298.11, 204/298.12, 118/723.AN, 118/723.I, 118/723.IR, 216/68, 156/345
• US Class Current: 204/298.06
• CPC Class Codes: C23C 16/507 using external electrodes, e.g. in tunnel type reactors
• CPC Class Codes: H01J 37/321 the radio frequency energy being inductively coupled to the plasma
• CPC Class Codes: H01L 21/3065 Plasma etching; Reactive-ion etching
• CPC Class Codes: H05H 1/46 using applied electromagnetic fields, e.g. high frequency or microwave energy H05H1/26 takes precedence

Abstract

In a high-frequency inductive plasma etching apparatus, a space between an antenna to which a high-frequency power is fed and a processing chamber is insulated with an insulating material having a suitable thickness, while the antenna is protected from a plasma or a reactive gas for plasma processing and the surface of a side in contact with the plasma is covered by an insulating material such as alumina and quartz. The insulating material and the antenna are placed in a vacuum. Since the processing chamber which contains the insulating material and the antenna can take a pressure differential with atmospheric pressure, all that is required of the insulating material is its capacity to take the plasma atmosphere. Consequently, the insulating material can be made thin and the plasma is generated uniformly in high density. Heat generated at the antenna is dissipated to the outside either by making a gap between the antenna and its surroundings as small as possible or by bringing the pressure of the gap closer to the pressure in the processing chamber. Alternatively, several Torr of a non-reactive heat-transfer promoting gas such as He gas may be introduced into fine gaps formed around the antenna to dissipate heat generated at the antenna.

Claims

1. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

antenna means for plasma generation is connected to said power source means, and said antenna means is covered with an insulating material integrated with said processing chamber,

wherein said antenna means includes first and second antennas, and each of said first and second antennas is connected to said power source means.

2. The plasma treatment device according to claim 1, wherein each of said first and second antennas includes a one-turn coil.

3. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

an antenna for plasma generation is connected to said power source means, and the antenna is covered with an insulating material integrated with said processing chamber,

wherein a shield plate comprising a conductive material is arranged between said antenna and a plasma generating space, and

wherein changing means for changing earth and non-earth of said shield plate is provided.

4. The plasma treatment device according to claim 3, wherein an insulating material having a thickness at least larger than a distance between the antenna and a plasma generating position is disposed between said processing chamber and said antenna.

5. The plasma treatment device according to claim 3, wherein said antenna is arranged opposite an upper surface of said mounting means.

6. The plasma treatment device according to claim 3, wherein a part surrounding said antenna in said processing chamber is formed of an insulating material.

7. The plasma treatment device according to claim 3, wherein means for introducing non-reactive gas having a pressure at least lower than atmospheric pressure is disposed in a space defined by said antenna in said chamber and an insulating material arranged around the periphery of said antenna.

8. The plasma treatment device according to claim 3 further comprising temperature detection means for detecting a temperature of said workpiece, temperature regulating means for regulating the temperature of said workpiece on the basis of the temperature detected by the temperature detection means, and refrigerant supply means for regulating the temperature of said antenna.

9. The plasma treatment device according to claim 3, wherein microwaves are applied to said antenna by said power supply means, and the frequency of the microwaves is in the range of 400 kHz to 100 MHz.

10. The plasma treatment device according to claim 3, wherein the workpiece which is mounted on the mounting means is a semiconductor wafer of a semiconductor device, the semiconductor wafer having a surface thereof plasma-processed by the plasma generated between the antenna and the semiconductor water which is disposed in the chamber opposite to the antenna, the antenna being formed integrally with the hermetically sealed processing chamber.

11. The plasma treatment device according to claim 3, wherein the workpiece which is mounted on the mounting means is a semiconductor wafer of a liquid crystal display substrate, the semiconductor wafer having a surface thereof plasma-processed by a plasma generated between the antenna and the semiconductor wafer which is disposed in the chamber opposite to the antenna, the antenna being formed integrally with the hermetically sealed processing chamber.

12. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

an antenna for plasma generation is connected to said power source means, and the antenna is covered with an insulating material integrated with said processing chamber,

wherein a shield plate comprising a conductive material is arranged between said antenna and a plasma generating space, and

wherein said shield plate is connected to a high-frequency power source.

13. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

an antenna for plasma generation is connected to said power source means, and the antenna is covered with an insulating material integrated with said processing chamber,

wherein a shield plate comprising a conductive material is arranged between said antenna and a plasma generating space, and

wherein said shield plate is connected to a DC power source.

14. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

an antenna for plasma generation is connected to said power source means, and the antenna is covered with an insulating material integrated with said processing chamber, and

further comprising an insulating material covering said antenna, first detection means for detecting a pressure of a space defined by the insulating material and said antenna, and second detection means for detecting a pressure in the processing chamber connected to the space via a communicating path having control means for opening and closing said communication path, wherein there is disposed means for opening said control means for opening and closing said communicating path when a pressure differential between the pressures detected by said first and said second detection means exceeds a predetermined value.

15. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

an antenna for plasma generation is connected to said power source means, and the antenna is covered with an insulating material integrated with said processing chamber,

wherein a shield plate comprising a conductive material is arranged between said antenna and a plasma generating space, and

wherein supply means for supplying non-reactive gas is disposed between said workpiece and said mounting means, and the supply means supplies the non-reactive gas for heat transfer promotion to a periphery of said antenna.

16. A plasma treatment device, comprising a hermetically sealed processing chamber, gas introducing means for introducing a processing gas, attached to the processing chamber, exhaust means for exhausting the processing gas introduced into said processing chamber, mounting means for mounting a workpiece, disposed in said processing chamber, and power source means for supplying power for plasma generation, characterized in that

an antenna for plasma generation is connected to said power source means, and the antenna is covered with an insulating material integrated with said processing chamber, wherein a shield plate comprising a conductive material is arranged between said antenna and a plasma generating space, and

wherein temperature detection means for detecting a temperature of a member placed in a vicinity of said antenna and non-reactive gas supply means for supplying non-reactive gas to the vicinity of said antenna are disposed to said member placed in the vicinity of said antenna, and pressure control means for controlling a pressure of the non-reactive gas is provided to the non-reactive gas supply means, and regulating means for regulating the temperature of said member in the vicinity of the antenna on the basis of the pressure of the non-reactive gas and the temperature of the member detected by said temperature detection means is provided.