SPECTROSCOPIC AND IMAGE INTENSIFIED INVESTIGATIONS OF RF PLASMAS IN H-2 AND CH4 MIXTURES

A computer-aided spectroscopic investigation system by means of an image processing technique has been developed for diagnosing various processing plasmas. This system, which is composed of a monochromator, two image intensifiers, a CCD camera and a personal computer, is characterised by the introduction of a digital signal processor and spatial filtering treatment of image data for fast image operations. The spectroscopic system is used to diagnose RF plasmas in H-2 and CH4 mixtures and in pure H-2. The results show that this system enables a spatiotemporally resolved optical emission spectra from plasmas to be obtained. It is found that the spatial and temporal resolutions are, respectively, 50 mum and 800 ns throughout the experiment, and that the needed operating time for detection of one spatial profile of the selected spectrum is 70 s.