Patent ID: 6758941
Filing Date: 2004-07-06
Classification: H01J

Abstract:
A plasma processing unit comprising;a processing container, a first electrode disposed in the processing container, the first electrode having a space connected to a process-gas supplying tube that supplies a process gas, a plurality of gas-dispersion holes formed on one side with respect to the space for supplying the process gas into the processing container, and an opening for a measurement of light formed on the side with respect to the space, a second electrode arranged on one side of a predetermined gap away from the gas-dispersion holes and the opening of the first electrode, a power source unit that applies electric power between the first electrode and the second electrode and that generates plasma between the first electrode and the second electrode, a window member having a non-transparent main body and a transparent material, the non-transparent main body having an optical path that adjacently communicates with the other side of the opening for the measurement of light, and a circular protrusion extending so as to surround the optical path and to come into contact with the first electrode, and a sealing member that is provided at the circular protrusion of the non-transparent main body to cause the space to be shut off from the optical path.