High-frequency power supply apparatus for plasma generation apparatus

• US 6,586,887 B1
• Filed: 03/06/2002
• Issued: 07/01/2003
• Est. Priority Date: 03/06/2002
• Status: Active Grant

• Current Assignee: Hitachi High-Tech Company Limited (Hitachi, Ltd.)
• Original Assignee: Hitachi High-Technologies Corporation (Hitachi, Ltd.)
• Inventors: Oogoshi, Yasuo, Kanekiyo, Tadamitsu, Takahashi, Youji, Umemoto, Tsuyoshi
• Primary Examiner(s): Wong, Don
• Assistant Examiner(s): VO, TUYET THI
• Application Number:
  US10/090,757
• Time in Patent Office: 482 Days
• Field of Search: 315/111.41, 315/111.21, 315/111.61, 315/291, 315/307, 315/500, 315/501, 315/502, 250/291, 250/285, 250/300, 250/286, 250/290, 250/294-299, 219/121.57, 219/121.54, 219/121.52
• US Class Current: 315/111.41
• 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 high-frequency power supply apparatus for a plasma generation apparatus having a modulator for generating an intermittent high-frequency output on the basis of a modulation reference signal and a peak value setting signal, the high-frequency power supply apparatus having: a first control loop for comparing the peak value of the intermittent high-frequency output detected by a peak value detector with a preset peak value of the high-frequency output so that the output controller controls the peak value of the high-frequency output to be the preset peak value; and a second control loop for calculating an average value of the intermittent high-frequency output based on the preset peak setting value and a preset duty ratio setting value and generating a modulation reference signal for controlling the modulator on the basis of the average value of the high-frequency output detected by a monitor and the average value of the high-frequency output.

Claims

1. A high-frequency power supply apparatus for a plasma generation apparatus having a modulator for generating an intermittent high-frequency output on the basis of a modulation reference signal and a peak value setting signal, said high-frequency power supply apparatus comprising:

a first control loop including a peak value detector for detecting a peak value of said intermittent high-frequency output, and an output controller for comparing the peak value of said intermittent high-frequency output detected by said peak value detector with a preset peak value of said high-frequency output so that said output controller controls the peak value of said high-frequency output to be said preset peak value; and

a second control loop including a monitor for detecting an average value of said intermittent high-frequency output, an arithmetic operation means for calculating an average value of said intermittent high-frequency output on the basis of the preset peak setting value and a preset duty ratio setting value, and a pulse generator for generating a modulation reference signal for controlling said modulator on the basis of the average value of said high-frequency output detected by said monitor and the average value of said high-frequency output calculated by said arithmetic operation means.

2. The high-frequency power supply apparatus for a plasma generation apparatus according to claim 1, wherein said pulse generator includes a display for displaying at least the average value of said high-frequency output detected by said monitor and the average value of said high-frequency output calculated by said arithmetic operation means.

3. The high-frequency power supply apparatus for a plasma generation apparatus according to claim 1, further comprising setting change-over means for changing-over setting of said peak value setting signal.

4. The high-frequency power supply apparatus for a plasma generation apparatus according to claim 2, wherein said pulse generator includes a display for displaying at least the average value of said high-frequency output detected by said monitor and the average value of said high-frequency output calculated by said arithmetic operation means.

5. The thigh-frequency power supply apparatus for a plasma generation apparatus according to claim 1, wherein said output monitor includes a monitor of a thermocouple system.

6. The high-frequency power supply apparatus for a plasma generation apparatus according to claim 3, wherein said output monitor includes a monitor of a thermocouple system.

7. A high-frequency power supply apparatus for a plasma generation apparatus according to claim 3, wherein said pulse generator includes a display for displaying at least the average value of said high-frequency output detected by said monitor and the average value of said high-frequency output calculated by said arithmetic operation means.

8. A high-frequency power supply apparatus for a plasma generation apparatus having a modulator for generating intermittent high-frequency output on the basis of a modulation reference signal, said high-frequency power supply apparatus comprising:

a monitor for detecting an average value of said intermittent high-frequency output; and

an arithmetic operation means for calculating an average value of said intermittent high-frequency output on the basis of a peak value setting signal and a duty ratio setting signal for said high-frequency output;

wherein said modulator is controlled on the basis of the average value of said high-frequency output detected by said monitor and the average value of said high-frequency output calculated by said arithmetic operation means.