Sensors in diffusion plasma processing

Several sensors developed at the Faculty of Electrical Engineering and mounted in a 50 kVA plasma nitriding unit are described. Special attention is given to a glow-to-arc transition instability sensor and hollow cathode effect sensor used for glow discharge stabilization. Specific characteristics of temperature and Pirani gauge sensors related to application in plasma processing are discussed and one type of double thermistor flowmeter which is still under testing presented.