短沟道SiC MESFET亚阈值特性  

Subthreshold characteristics of short-channel SiC MESFETs

作　　者：韩茹[1] 杨银堂[1] 贾护军[1] 

机构地区：[1]西安电子科技大学微电子学院宽禁带半导体材料与器件教育部重点实验室,西安710071

出　　处：《功能材料与器件学报》2008年第4期810-814,共5页Journal of Functional Materials and Devices

基　　金：国防预研项目(No.51308030201);国防预研项目(No.51323040118)

摘　　要：基于器件物理分析的方法,结合沟道电势二维解析模型,分析比较了漏极引致势垒降低效应(DIBL effect)对6H-及4H-SiC MESFET沟道势垒,阈值电压,以及亚阈值电流的影响,并研究了其温度特性。研究表明DIBL效应的存在使SiC MESFET的沟道势垒最小值随栅长及温度发生变化,并带来阈值电压及亚阈值电流的变化。栅长越大,温度越高,亚阈值倾斜因子Ns越小,栅压对沟道电流的控制能力增强,最终造成亚阈值电流随栅压的变化越快。Abstract： Drain -induced barrier lowering effect （DIBL effect） on the subthreshold behavior is studied in 6H - and 4H - SiC MESFETg through an analytical two - dimensional model. Based on the physical analysis, the temperature dependences of channel potential, threshold voltage and subthreshold current for 6H - and 4H - SiC MESFET＇s are investigated. The simulation results show that as the existence of DIBL effect, the channel potential minimum varies with the gate length and temperature, bringing the variation of threshold voltage and the subthreshold current of SiC MESFETs. In addition, the subthreshold slope factor Ns is inversely proportional to the gate length and temperature. The smaller Ns indicates that the gate voltage strongly controls the drain current, finally, bringing a larger slope of the linear part in the logIds- Vgs relationship.

关 键 词：碳化硅MESFET 沟道电势 漏极引致势垒降低效应 阈值电压 

分 类 号：TN386[电子电信—物理电子学]