Control of grain size and crystallinity of poly-Si films on quartz by Al-induced crystallization†
The crystalline properties of poly-Si films on quartz grown using Al-induced crystallization (AIC) were investigated. The orientation fraction and grain size were controlled by modulating the annealing temperature and sample thickness. The results confirmed the enhancement of (111)-orientation fractions and grain size by lowering the annealing temperature and reducing the thickness. The effects of both parameters, annealing temperature and thickness, on the growth process were investigated, as was the role of the Al layer. We successfully formed (111)-oriented grains up to 384 μm in size at a rate of 99% in a 50 nm-thick sample annealed at 400 °C. Furthermore, the real applications of AIC poly-Si as a growth template were demonstrated through silicon thin-film and nanowire formation.