摘要 |
PURPOSE:To improve the operability of a plasma processor by cleaning a reactive product adhered into a processing chamber by oxygen plasma, measuring the intensity of the light spectrum of the generated reactive product to judge the end of the cleaning, thereby performing cleaning without breaking the vacuum of the chamber. CONSTITUTION:A reactive product adhered into a process chamber 2 of a plasma processor for plasma-processing with reactive gas containing carbon or hydrogen is cleaned by an oxygen plasma, the intensity of the light spectrum of the product is measured to judge the end of the cleaning. For example, the wavelength light of the spectrum of CO, CO2 or H2O in the plasma light generated by the reaction during the cleaning is spectrally analyzed by a spectroscope 8, converted by a photoelectric converter 9 into an electric signal, amplified by an amplifier 10, and input to a microcomputer 11 for controlling the entire processor. As the cleaning advances, the product decreases, and when the intensity of the spectrum decreases, the microcomputer 11 detects it as the decrease in the output voltage of the amplifier 10, and when the voltage falls lower than the set value, the cleaning is finished. |