Source of surface defects in silicon carbide epitaxial files and their elimination method

碳化硅外延锉表面缺陷的来源及消除方法

基本信息

批准号：
16560009
负责人：
OKADA Tatsuya
金额：
$ 2.66万
依托单位：
The University of Tokushima
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2004
资助国家：
日本
起止时间：
2004 至 2007
项目状态：
已结题

项目摘要

Silicon carbide (SIC) has been attracting much attention because of its application to power devices exhibiting superior performance to conventional Si-based ones. large-area epitaxial films of high quality are essential for the fabrication of kV-class high-power SiC devices. However ; at the present stage, imperfections in epitaxial films including surface defects impose a limitation on high-yield production of such devices. When formed, some types of surface defect deteriorate device performance by lowering the breakdown voltage of p-n junctions by 20 to 40%. The major objectives of the present study are to investigate the source of surface defects at the substrate/epifilm interface by plan-view transmission electron microscopy (TEM) and to find a technique to eliminate crystallographic defects accompanying surface defects.We were successful in preparing plan-view TEM samples which contain the substrate/epifilm interface in the thinned area by removing almost the entire epifilm with … More reactive plasma-etching prior to the conventional ion-thinning from the substrate side. The source of surface defects was composed of an inclusion and partial dislocations. Energy dispersive X-ray (EDX) spectroscopy and micro-Raman analysis unraveled that the inclusions were very small particles of zirronia (ZrO_2). The thermal insulator in the chemical vapor deposition (CVD) furnace is the most suspicious origin of ZrO_2 particles. The ZrO_2 particles which fell onto the SiC substrate surface and were ncorporated into the epifilm may have acted as the source of partial dislocations, which resulted in the formation of surface defects.We propose that phase change induced by irradiation of ultra-short laser pulses may be applied to the elimination of defects in SiC epitaxial films. When femtosecond laser pulses are irradiated on the surface of SiC, periodic surface microstructures referred to as ripples are formed. In order to study the cross-sectional microstructures of ripples, we carried out TEM studies with particular attention on the crystal structure underlying ripples. A continuous amorphous layer approximately 10 to 50 nm thick was found to cover the topmost region of ripples. Less

碳化硅（SIC）因其在功率器件中的应用而受到广泛关注，其性能优于传统的硅基器件，高质量的大面积外延薄膜对于制造kV级高功率SiC器件至关重要。然而，在现阶段，外延膜中的缺陷（包括表面缺陷）限制了此类器件的高产量生产，某些类型的表面缺陷会使p-n结的击穿电压降低20倍，从而使器件性能恶化。本研究的主要目标是通过平面透射电子显微镜 (TEM) 研究基板/外延膜界面表面缺陷的来源，并找到一种消除伴随表面缺陷的晶体学缺陷的技术。在从基底一侧进行传统离子减薄之前，通过反应性等离子蚀刻去除几乎整个外延膜，成功制备了在减薄区域包含基底/外延膜界面的平面视图 TEM 样品。表面缺陷的来源是。组成的能量色散X射线（EDX）光谱和显微拉曼分析表明，化学气相沉积（CVD）炉中的绝热体是非常小的氧化锆（ZrO_2）颗粒。 ZrO_2 颗粒的可疑来源落在 SiC 衬底表面并掺入外延膜中的 ZrO_2 颗粒可能是部分的来源。位错，导致表面缺陷的形成。我们提出，当飞秒激光脉冲照射到 SiC 表面时，超短激光脉冲照射引起的相变可用于消除 SiC 外延薄膜中的缺陷。形成称为波纹的周期性表面微观结构，为了研究波纹的横截面微观结构，我们进行了 TEM 研究，特别关注波纹下方的晶体结构。发现约 10 至 50 nm 厚的非晶层覆盖了波纹的最顶部区域。

项目成果

期刊论文数量（39）

专著数量（0）

科研奖励数量（0）

会议论文数量（0）

专利数量（0）

Tem/Hrem Analysis of Defects in GaN Epitaxial Layers Grown by MOVPE on SiC and Sapphire

SiC 和蓝宝石上 MOVPE 生长的 GaN 外延层缺陷的 Tem/Hrem 分析

DOI：
10.1557/proc-468-287
发表时间：
1997-09-14
期刊：
MRS Proceedings
影响因子：
0
作者：
S. Ruvimov;Z. Liliental;C. Dieker;J. Washburn;M. Koike;H. Amano;I. Akasaki
通讯作者：
I. Akasaki

Schottky Barriers for Pt, Mo and Ti on 6H and 4H SiC (0001), (000-1), (1-100) and (1-210) Faces Measured by I-V, C-V and Internal Photoemission

通过 I-V、C-V 和内部光电发射测量 6H 和 4H SiC (0001)、(000-1)、(1-100) 和 (1-210) 面上 Pt、Mo 和 Ti 的肖特基势垒

DOI：
10.4028/www.scientific.net/msf.433-436.705
发表时间：
2002-04-01
期刊：
Materials Science Forum
影响因子：
0
作者：
O. Shigiltchoff;S. Bai;R. Devaty;W. J. Choyke;T. Kimoto;H. McD. Hobgood;P. Neudeck;L. Porter
通讯作者：
L. Porter

Crystallographic defects under surface morphological defects of 4H-SiC homoepitaxial films

4H-SiC同质外延薄膜表面形貌缺陷下的晶体缺陷