Journal of South China University of Technology(Natural Science Edition) ›› 2012, Vol. 40 ›› Issue (3): 64-68,125.

• Electronics, Communication & Automation Technology • Previous Articles     Next Articles

Direct Current Model of Polysilicon Thin Film Transistor Based on Discrete Grain Boundary Distribution

Yan Bing-hui1  Li Bin1  Yao Ruo-he1  Wu Wei-jing2   

  1. 1.School of Electronic and Information Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China; 2.School of Materials Science and Engineering,South China University of Technology,Guangzhou 510640,Guangdong,China
  • Received:2011-08-14 Revised:2011-11-02 Online:2012-03-25 Published:2012-02-01
  • Contact: 李斌(1967-) ，女，教授，博士生导师，主要从事深亚微米器件建模与集成电路可靠性、半导体器件与系统集成研究． E-mail:phlibin@scut.edu.cn E-mail:binghuiyan@126.com
  • About author:严炳辉(1982-) ，男，博士生，主要从事半导体器件模型及电路仿真研究．
  • Supported by:

    国家自然科学基金资助项目( 60776020) ; 国际合作项目( B14D8061610) ; 华南理工大学中央高校基本科研业务费专项资金资助项目( x2clD2104790)

PDF

1102

Abstract:

The drain current model of the polysilicon thin film transistor ( poly-Si TFT) based on surface potential can not accurately describe the discrete grain boundary distribution,while the threshold-voltage-based model is not capable of continuously representing the drain currents in different operation regions. In order to solve these problems,a direct drain current model of the poly-Si TFT considering the discrete distribution of grain boundary potential in drains is established based on the surface potential. The proposed model describes the drain currents of the poly-Si TFT in different operating regions via an analytic equation.  Simulated results indicate that,when the poly-Si TFT works in the linear region at a certain gate bias,its effective mobility decreases with the increase in drain voltage,and that,with the increase in gate bias or with the decrease in channel length,the effect of drain voltage on the effective mobility weakens.

Key words: polysilion, thin film transistor, current model, discrete grain boundary, surface potential, effective mobility