Evaluation of BJTs as closing switch of miniaturized Marx generator

The micro plasma technology is used in various fields such as processing or chemical analysis of minute material, short-wavelength light source, and plasma function device. The plasmas can be generated by an electric discharge. The miniaturized generator was used to produce these plasmas in the micro-scale area. For such background, the miniaturized Marx generator which has Bipolar Junction Transistors (BJTs) as closing switches was developed to generate micro plasmas. In the miniaturized Marx generator, BJTs were operated in avalanche mode to obtain a faster switching speed with ns order. In this paper, three kinds of BJTs which have different collector current each others were evaluated as closing switch. In the experiment, the BJTs were operated in avalanche mode with higher applied voltage (about twice voltage rating) into the between collector and emitter of BJTs. As the result, as Vc increases, the switching time of BJTs which operated in the avalanche mode was decreases. And, the peak of Ic of three kinds of BJTs which operated in avalanche mode was almost same.