MOSFET의 RF 성능 최적화를 위한 단위 게이트 Finger 폭에 대한 $f_T$$f_{max}$의 종속데이터 분석

Analysis of $f_T$ and $f_{max}$ Dependence on Unit Gate Finger Width for RF Performance Optimization of MOSFETs

  • 차지용 (한국외국어대학교 전자정보공학부) ;
  • 차준영 (한국외국어대학교 전자정보공학부) ;
  • 정대현 (한국외국어대학교 전자정보공학부) ;
  • 이성현 (한국외국어대학교 전자정보공학부)
  • Cha, Ji-Yong (School of Electronics and Information Engineering, Hankuk University of Foreign Studies) ;
  • Cha, Jun-Young (School of Electronics and Information Engineering, Hankuk University of Foreign Studies) ;
  • Jung, Dae-Hyoun (School of Electronics and Information Engineering, Hankuk University of Foreign Studies) ;
  • Lee, Seong-Hearn (School of Electronics and Information Engineering, Hankuk University of Foreign Studies)
  • 발행 : 2008.09.25

초록

본 연구에서는 MOSFET의 RF 성능을 극대화하기 위해 단위 게이트 finger 폭($W_u$)에 대한 $f_T$$f_{max}$의 종속데이터를 측정하고 이 결과를 소신호 모델 파라미터들을 추출함으로써 새롭게 분석하였다. 이러한 물리적 분석결과로 $f_T$의 최대값이 존재하는 원인은 좁은 $W_u$에서 $W_u$에 무관한 parasitic gate-bulk capacitance와 넓은 $W_u$에서 트랜스컨덕턴스의 증가율이 감소하는 wide width effect에 의한 것임을 알 수 있다. 또한, $f_{max}$의 최대값은 게이트저항이 좁은 $W_u$에서 크게 줄어들고 넓은 $W_u$에서 점점 일정하게 되는 non-quasi-static effect에 의해 발생된다는 사실이 밝혀졌다.

In this study, to maximize RF performance of MOSFETs, $f_T$ and $f_{max}$ dependent data on $W_u$ are measured and newly analyzed by extracting small-signal model parameters. From the physical analysis results, it is found that a peak value of $f_T$ is generated by $W_u$-independent parasitic gate-bulk capacitance at narrow $W_u$ and the wide width effect of reducing the increasing rate of transconductance at wide $W_u$. In addition, it is revealed that a maximum value of $f_{max}$ is caused by the non-quasi-static effect that the gate resistance is greatly reduced at narrow $W_u$ and becomes constant at wide $W_u$.

키워드

참고문헌

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