摘要
采用电子束蒸发技术在衬底温度为180℃条件下生长具有Ge覆盖层的非晶Si薄膜,并于500℃、600℃、700℃真空退火5 h。采用Raman散射、X射线衍射(XRD)、全自动数字式显微镜等对所制备薄膜的晶化特性进行研究。结果表明,Ge覆盖层具有诱导非晶Si薄膜晶化的作用,且随着退火温度的升高a-Si薄膜晶化越显著。具有Ge覆盖层非晶薄膜经500℃退火5 h沿Si(400)方向开始晶化,对应晶粒尺寸约为4.9 nm。将退火温度升高到700℃时,非晶硅薄膜几乎全部晶化,晶化多晶Si薄膜在Si(400)方向表现出很强的择优取向特性,晶粒尺寸高达23.3μm。与相同条件下制备的无Ge覆盖层的非晶Si薄膜相比,晶化温度降低了300℃。
a-Si thin films with a capping layer of Ge （a-Si/Ge films） were deposited on Si substrates at 180 ℃ by electron beam evaporation（EBE） , and then annealed for 5 h at 500 ℃, 600 ℃, 700 ℃ in vacuum. The annealed films were investigated by Raman scattering, X-ray diffraction （XRD） and Automatic digital microscope. The results show that the capping Ge can induce a-Si crystallization, and as the annealing temperature increasing, the crystallization of a-Si films become more significant. The a- Si begin to crystallize with orientation of Si（400） annealed at 500 ℃ for 5 h, and the corresponding grain sizes is about d. 9 nm. When the annealing temperature increased to 700 ℃, the crystallized film has a strong preferred orientation of Si （ 400 ）, the grain size is as large as 23.3 μm. The crystallization temperature decreased by 300℃ compared to that a-Si film without Ge capping layer.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2015年第2期420-424,共5页
Journal of Synthetic Crystals
基金
国家国际科技合作专项项目(2011DFA62380)
云南省自然科学基础研究项目(2010DC053)
关键词
多晶硅薄膜
电子束蒸发
非晶硅
Ge诱导晶化
poly-Si films
electron beam evaporation
amorphous silicon
Ge-induced crystallization
