Si(100)衬底上n-3C-SiC/p-Si异质结构研究  

Investigation of n-3C-SiC/p-Si Heterojunctions on Si(100)

作　　者：孙国胜[1] 孙艳玲[1] 王雷[1] 赵万顺[1] 罗木昌[1] 李建平[1] 曾一平[1] 林兰英[1] 

机构地区：[1]中国科学院半导体研究所,北京100083

出　　处：《发光学报》2003年第2期130-134,共5页Chinese Journal of Luminescence

基　　金：国家重点基础研究专项经费基金(G20000683);国家863高技术研究与发展项目基金(2001AA311090)资助项目

摘　　要：利用LPCVD方法在Si(100)衬底上获得了3C SiC外延膜,扫描电子显微镜(SEM)研究表明3C SiC/p Si界面平整、光滑,无明显的坑洞形成。研究了以In和Al为接触电极的3C SiC/p Si异质结的I V,C V特性及I V特性的温度依赖关系,比较了In电极的3C SiC/p Si异质结构和以SiGe作为缓冲层的3C SiC/SiGe/p Si异质结构的I V特性,实验发现引入SiGe缓冲层后,器件的反向击穿电压由40V提高到70V以上。室温下Al电极3C SiC/p Si二极管的最大反向击穿电压接近100V,品质因子为1 95。Recently there has been an increased effort to develop cubic (3C) SiC owning t o its high electron mobility and highsaturation drift velocity for the fabricat i on of highpower and hightemperature electronic devices. In this paper, we re po rt on the growth and electrical properties of voidsfree n3CSiC/pSi heter ojun ctions grown by LPCVD. The substrates are 2inch ptype Si (100) wafers with r es istivity of 10～12Ω·cm. SiH4, C2H4, and Pdcell purified H2 were used as precurso r gases with flow rates of 2, 3sccm, and 3 000sccm, respectively. The LPC VD method at 532×104Pa was employed to grow 3CSiC epitaxial films. In ord er to pr event the formation of voids and obtain improved interface of 3CSiC/Si, much a t tention has been paid to the pretreatment and carbonization process of the subst rates. It was obtained that the SiC/Si interface is smooth and there is no obvio us voids formed in the Si substrate surface. This result indicates that the out  diffusion of Si atoms from Si substrates was suppressed during the epitaxial gro wth of SiC at 1 250℃. Halleffect measurements were performed to investiga te th e electrical properties of the grown films with about 15μm in thickness in t he temperature range from 80 to 300K. The mobility was 408cm2/Vs with the carr ie r concentration was about 72×1017cm-3 at room temperature. Hall mobility obeys the T-α law in temperature range from 300 to 130K, where the value of α is 12. The IV, CV, and the temperature dependence of IV curves in 3CSiC heter ojun ctions with indium (In) and aluminum (Al) electrical pads, respectively, were in vestigated. The heterojunctions diodes (HJDs) with 05～1mm2 in area were obt ain ed by cleaving n3CSiC/pSi. It was shown that with the introduction of a th in SiGe buffer layer between 3CSiC and Si substrate, the reverse breakdown voltag e

关 键 词：硅衬底 Si(100)衬底 n-3C-SiC/p-Si异质结 结构研究 3C-SiC外延膜 碳化硅 扫描电子显微镜 SEM 

分 类 号：TN304.24[电子电信—物理电子学] O475[理学—半导体物理]