摘要
利用室温光致发光谱(PL)对CVD法生长的4H-SiC同质外延特性进行研究,发现有绿带发光(GL)特性.用扫描电子显微镜(SEM)、二次离子质谱(SIMS)和X射线光电子谱(XPS)技术获得了4H-SiC样品纵截面形貌和元素相对含量分布.结果表明,GL与4H-SiC晶体中碳空位(VC)及络合体缺陷相关,VC和缓冲层的扩展缺陷(点缺陷和刃位错等)是GL微观来源.GL的半峰宽(FWHM)反映了参与复合发光的VC及其络合缺陷能级分散的程度.室温下获得的样品GL强度和光谱波长度可用于分析4H-SiC外延中缺陷分布和晶体质量.
The Green-band luminescence （GL） from an Al-doped 4H-SiC Homoepitaxial layer prepared by using chemical vapur deposition （CVD） has been observed and studied. The deep pattern obtained by SEM and the buffer layer can be found in the interface between SiC substrate and epilayer. The deep profiles of Si atom in 4H-SiC epilayers obtained by using the secondary ion mass spectrometry （SIMS） and the X-ray photoelectron spectroscopy （XPS） show the relative distribution of Si and C. The results strongly suggest that the vacancy of C and the extended defects （point defects, threading dislocations, et al） from buffer layer are responsible for the GL emission. The full width at half maximum （FWHW） of GL indicates the distributions of Vc and its complex defects, The quality of crystals and the distribution of defects in epitaxial layers can be characterized by the intensity and the wavelength of GL obtained from samples at room temperature.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2008年第7期4456-4458,共3页
Acta Physica Sinica
基金
国家重点基础研究发展计划(973)(批准号:51327020202)
西安-应用材料创新基金(批准号:XA-AM-200704)资助的课题~~
关键词
绿带发光
4H-SiC同质外延
晶体缺陷
Green-band luminescence, 4H-SiC homoepitaxial layers, crystal defect
