Patent ID: 6675816
Filing Date: 2004-01-13
Classification: C23C,H01J,H05H,Y10S

Abstract:
A dry cleaning method of the parallel flat plate type plasma CVD apparatus comprising:a high frequency power supply; a first electrode; a second electrode; a matching circuit between the high frequency power supply and the first electrode and between the high frequency power supply and the second electrode; a first change-over switch between the high frequency power supply and the first electrode and between the high frequency power supply and the second electrode; a pulse amplitude modulation circuit between the high frequency power supply and the first electrode and between the high frequency power supply and the second electrode; an inverter circuit between the first change-over switch and the second electrode; a second change-over switch between the first change-over switch and the second electrode; a wiring line for ground between the first change-over switch and the second electrode; said method comprising the steps of: supplying etching gas into a reaction chamber; applying a pulse amplitude modulated high frequency voltage through the pulse amplitude modulation circuit to the first electrode by changing the first change-over switch; applying a high frequency voltage having a phase shifted by 180Â° from the first electrode to the second electrode in order to produce plasma of said etching gas, said high frequency voltage being pulse amplitude modulated through the pulse amplitude modulation circuit by changing the first change-over switch and being through the inverter circuit by changing the second change-over switch; and cleaning an inside of said reaction chamber by using said plasma.