SiC/SiO_2界面形貌对SiC MOS器件沟道迁移率的影响  

Effection of morphology of SiC/SiO_2 interface on mobility characteristics of MOS devices

作　　者：刘莉[1] 杨银堂[1] 

机构地区：[1]西安电子科技大学微电子学院,陕西西安710071

出　　处：《浙江大学学报（工学版）》2016年第2期392-396,共5页Journal of Zhejiang University：Engineering Science

基　　金：国家自然科学基金青年基金资助项目(61404096);国家自然科学基金重点资助项目(61334003)

摘　　要：为了研究SiC/SiO_2界面粗糙度对SiC MOS器件构道迁移率的影响,在离子注入后高温退火过程中采用碳膜保护SiC表面以减小退火过程中产生的表面粗糙度,碳膜的形成通过对光刻胶在600℃下前烘30min实现.研究结果表明:微结构分析所得的微米量级的横向表面粗糙度(峰对峰,谷对谷)不会影响电子平均自由程为纳米数量级的沟道电子在SiC MOS器件沟道中的迁移运动,在高温退火过程中,碳膜的是否存在对表面粗糙度和NMOS电容SiC/SiO_2界面态密度没有影响,而且NMOSFET器件的场效应迁移率没有发生太大的变化.To investigate the effects of SiC/SiO2 interface roughness on the mobility of 4H-SiC MOS capacitors and MOSFETs, carbon cap protection to the surface of SiC was used to reduce the surface roughness during high temperature annealing after ion implantation. Carbon cap is formed by annealing photo-resistant for 30min. It is shown that because micro-scale lateral surface roughness （peak to peak/ valley to valley） does not affect the movement of channel electrons with nm scale mean free path in the SiC MOS channel, so in the duration of the high temperature annealing regardless of where there is carbon-cap existence or not and surface roughness is changed or not, the De measured from NMOS capacitors are almost identical and channel mobility in the MOSFET do not been changed ultimately.

关 键 词：SiC/SiO2界面粗糙度 界面态密度 场效应迁移率 

分 类 号：TN43[电子电信—微电子学与固体电子学]