Patent ID: 7931776
Filing Date: 2011-04-26
Classification: H01J,H01L

Abstract:
1. A plasma processing apparatus, comprising: a chamber in which inner parts with a protective coating thereon are disposed on an inner wall of the chamber; a sample stage disposed in the chamber, the sample stage including a wafer attracting electrode on a sample placing surface thereof, the electrode being insulated from the sample stage by an insulating layer; a gas introducing unit including a gas injection plate which disperses and introduces processing gas into the chamber; a plasma generating high-frequency wave power source which supplies high-frequency wave energy to the processing gas introduced into the chamber to thereby generate plasma; a bias applying high-frequency wave power supply which applies a high-frequency bias voltage to the sample stage; a wafer attracting power source which applies a direct-current voltage to the wafer attracting electrode to attract a wafer, thereby conducting plasma processing for the sample placed on the sample stage using the plasma thus generated; a wafer attracting current monitor for monitoring a current supplied from the wafer attracting power source; an impedance monitor provided on a plasma generating side, for monitoring an impedance of the plasma viewed from the plasma generating high-frequency power source; an impedance monitor provided on a bias applying side, for monitoring an impedance of the plasma viewed from the bias applying high-frequency power supply; and a determining device for determining, based on monitor values measured by the monitors, a presence or an absence of abnormal discharge in the inner parts, a deterioration in insulation of the sample stage insulating the wafer attracting electrode, and an abnormal discharge in the gas injection plate, wherein the determining device determines presence of insulation breakdown in the protective coating on the inner parts when the monitor value of the wafer attracting current monitor abruptly increases pulse-wise and no variation appears in the monitor value of the impedance monitor on the plasma generating side and the monitor value of the impedance monitor on the bias applying side.