Plasma processing apparatus

• US 5,705,019 A
• Filed: 04/23/1996
• Issued: 01/06/1998
• Est. Priority Date: 10/26/1994
• Status: Expired due to Term

• Current Assignee: Tokyo Electron Limited
• Original Assignee: Sumitomo Metal Industries Limited (Nippon Steel Corporation)
• Inventors: Yamada, Minoru, Hayami, Toshihiro
• Primary Examiner(s): POWELL, WILLIAM A
• Application Number:
  US08/636,352
• Time in Patent Office: 623 Days
• Field of Search: 156/345 P, 156/345 V, 156/643.1, 156/662.1, 204/298.34, 204/298.39, 216/67
• US Class Current: 156/345.44
• CPC Class Codes: H01J 37/32082 Radio frequency generated discharge H01J37/32357, H01J37/32366, H01J37/32394 and H01J37/32403 take precedence
• CPC Class Codes: H01J 37/32174 Circuits specially adapted for controlling the RF discharge

Abstract

A plasma processing apparatus comprises a reaction chamber, an upper electrode, a lower electrode which confronts the upper electrode and also functions as a sample stage, means of supplying RF power between the upper electrode and lower electrode such that the RF power is supplied to one of the upper and lower electrodes, with another electrode and the reaction chamber being grounded, and RF impedance matching means, wherein the capacitance between the grounded electrode and the reaction chamber is 125 pF or less. The apparatus is capable of stabilizing the plasma generation and alleviating the occurrence of sudden deterioration of the repeatability of plasma processing and unequal performance of plasma processing among individual apparatus. The apparatus can be applied suitably to etching apparatus having small electrode spacing and using a chlorine compound gas or a bromine compound gas such as Cl₂ or HBr.

Claims

1. A plasma processing apparatus comprising:

a reaction chamber;

an upper electrode;

a lower electrode which confronts said upper electrode and also functions as a sample stage;

means of supplying RF power between said upper electrode and said lower electrode, said RF power being supplied to one of said upper or lower electrode, with another of said electrodes and said reaction chamber being grounded, and

means of matching the RF impedance,

wherein the capacitance between the grounded electrode and said reaction chamber is 125 pF or less.

2. A plasma processing apparatus according to claim 1, wherein the grounded electrode is insulated from said reaction chamber with an insulation member having a relative dielectric constant of 3.6 or less.

3. A plasma processing apparatus according to claim 1, wherein the spacing between said upper electrode and said lower electrode is 5 mm or more and 15 mm or less.

4. A plasma processing apparatus comprising:

a reaction chamber;

an upper electrode;

a lower electrode which confronts said upper electrode and also functions as a sample stage;

means of supplying RF power between said upper electrode and said lower electrode, said RF power being supplied to one of said upper or lower electrode, with another of said electrodes and said reaction chamber being grounded;

means of matching the RF impedance; and

means of varying the capacitance between the grounded electrode and said reaction chamber.

5. A plasma processing apparatus according to claim 4, wherein the spacing between said upper electrode and said lower electrode is 5 mm or more and 15 mm or less.