Method for controlling the operation of a microwave-excited oxygen plasma surface treatment apparatus

摘要

A method for sequentially controlling the operation of a microwave-excited oxygen plasma surface treatment apparatus in order to improve and control the quality of surface treatment. The pressure within a reactor (10) is continuously monitored and measured and a first pressure signal is issued when the pressure is reduced to a predetermined first level, whereupon flow control valves (52, 54) are opened to allow oxygen gas to flow through microwave discharge tubes (34) into the reactor (10). A second pressure signal is issued when the pressure increases to a second pressure range and microwave power generators (20, 22) are energized to excite the oxygen flowing therethrough. The plasma density is continuously monitored and measured, preferably in terms of the luminous intensity of the plasma, the amount of reflected microwave power, or a combination thereof. The plasma surface treatment is terminated after a timed duration.