摘要
铝诱导晶化法(AIC)是一种低温制备大晶粒多晶硅薄膜的重要方法。本文分别基于Al/Al2O3/a-Si叠层和a-Si/SiOx/Al叠层制备了AIC多晶硅薄膜,前者表面粗糙,后者表面光滑。以后者为籽晶层,在其上用HWCVD法300℃低温下外延生长了表面形貌与籽晶层相似的多晶硅薄膜。铝诱导晶化过程中,在原始非晶硅层中会形成多晶硅、非晶硅和铝的混合层,去除铝后残留的硅将使表面粗糙,而在原始铝层中则形成连续的多晶硅薄膜。Al/Al2O3/a-Si叠层和a-Si/SiOx/Al叠层的上层分别是非晶硅层和铝层,发生层交换后,前者上层是硅铝混合层,因此表面粗糙,后者上层是连续的多晶硅薄膜,因此表面光滑。在AIC多晶硅薄膜表面外延生长多晶硅薄膜等效于铝诱导多晶硅的晶核在垂直于薄膜方向上的继续生长,因此外延生长的薄膜与AIC多晶硅薄膜呈现相似的枝晶状形貌。
Aluminum induced crystallization（AIC） is an important method to prepare polycrystalline silicon（poly-Si） at low temperature.In this paper,high quality aluminum induced crystalline silicon was prepared from glass/aluminum/alumina/amorphous（Al/Al2O3/a-Si） stack and glass/amorphous/silicate/aluminum（a-Si/SiOx/Al） stack,respectively.The SEM of the films show that the poly-Si from Al/Al2O3/a-Si stack was very rough,and the other was smooth.The AIC poly-Si films from a-Si/SiOx/Al stacks were used as seeding layer to epitaxially grow high crystalline quality poly-Si films at 300 ℃ temperature by HWCVD.The mechanism of the difference of the surface topography between the poly-Si from the two stacks was discussed.During the AIC process,the mixture layer of poly-Si,a-Si and Al was formed in the original a-Si layer.After aluminum was etched,the residual silicon surface becomes rough.And continuous high quality poly-Si was formed in the original Al layer.The top layers of Al/Al2O3/a-Si and a-Si/SiOx/Al stacks were a-Si and Al respectively.After layer exchange process,the top layer of the former is silicon and aluminum mixture,so the surface is rough.On the other hand,the top layer of the latter is continuous poly-Si,so the surface is smooth.The epitaxial growth of poly-Si on AIC poly-Si surface is equivalent to the AIC silicon nucleus＇ continuously growing at vertical direction of the film.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2012年第6期1757-1761,共5页
Journal of Synthetic Crystals
基金
国家自然科学基金项目(61176062)
江苏省优势学科资助项目
金陵科技学院博士启动基金(jit-b-201206)
关键词
多晶硅薄膜
铝诱导晶化
热丝化学气相沉积
外延生长
polycrystalline silicon thin film
aluminum-induced crystallization
hot wire chemical vapor deposition
epitaxial growth
