The Transient Response of CF$_4$ RF Plasmas Using One-dimensional Fluid Model

1차원 유체모델을 이용한 CF$_4$ RF 플라즈마의 과도응답 특성

  • 소순열 (북해도대학교 전자정보공학과) ;
  • 임장섭 (목포해양대학교 전자통신공학과)
  • Published : 2004.01.01

Abstract

$CF_4$ gas is one of the most useful gases in modern technologies for semiconductor fabrication. However, there are many problems which should be solved in order to fabricate semiconductor device, for example, etching speed drop due to ion charge-up and etching selectivity drop due to the high electron energy. One of useful method in order to suppress their damages above is pulsed-time modulated plasma (PM). However, transient responses of charged particles occur when the source power is turned-on and -off in PM method. To control plasma properties in detail, such a transient phenomenon must be investigated. In this paper, we investigate $CF_4$ RF plasma properties under a one-dimensional fluid model. And also for dynamic and stable control of $CF_4$ plasmas, we investigated the transient behavior of the plasmas after step up or down of the amplitude of the power source voltage $V_s$(t). Fundamental properties of transient $CF_4$ plasmas was discussed. Furthermore, we intend to discuss new method for pulsed-time plasma modulation.

Keywords

CF$_4$;Modeling;Transient Response;RF plasma

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