Implementation of Stretched-Exponential Time Dependence of Threshold Voltage Shift in SPICE

Stretched-Exponential 형태의 문턱전압 이동 모델의 SPICE구현

  • Jung, Taeho (Department of Electronic and IT Media Engineering, Seoul National University of Science and Technology)
  • 정태호 (서울과학기술대학교 전자IT미디어공학과)
  • Received : 2020.03.10
  • Accepted : 2020.03.23
  • Published : 2020.03.31


Threshold voltage shift occurring during operation is implemented in a SPICE simulation tool. Among the shift models the stretched-exponential function model, which is frequently observed from both single-crystal silicon and thin-film transistors regardless of the nature of causes, is selected, adapted to transient simulation, and added to BSIM4 developed by BSIM Research Group at the University of California, Berkeley. The adaptation method used in this research is to select degradation and recovery models based on the comparison between the gate and threshold voltages. The threshold voltage shift is extracted from SPICE transient simulation and shows the stretched-exponential time dependence for both degradation and recovery situations. The implementation method developed in this research is not limited to the stretched-exponential function model and BSIM model. The proposed method enables to perform transient simulation with threshold voltage shift in situ and will help to verify the reliability of a circuit.



Supported by : 서울과학기술대학교

이 연구는 서울과학기술대학교 교내연구비의 지원으로 수행되었습니다.


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