Temperature dependent aluminum induced crystallization of amorphous germanium thin films

In this work, we present the sequential growth of metal-semiconductor bilayer structure on HF-treated textured glass substrates by thermal evaporation method. The process of aluminum-induced crystallization of amorphous germanium thin films was critically observed under heat treatment. Temperature assisted structural modifications triggered the nucleation phenomenon for controlled grain growth which transformed the nature of Ge-thin film from amorphous-to-polycrystalline. Interestingly, the electrical resistivity also decreased by subsequent annealing which promoted the conduction mechanism. Optical measurements indicated a dwindling in band tail states and related structural defects, leading to better crystallinity.

Automated summary

In this study, we successfully achieved the sequential growth of metal-semiconductor bilayer structure on textured glass substrates treated with HF using the thermal evaporation method. The crystallization of amorphous germanium thin films induced by aluminum was critically observed during the heat treatment process. The resulting temperature-assisted structural modifications led to controlled grain growth and a transformation from amorphous-to-polycrystalline for the Ge-thin film. Subsequent annealing also reduced the electrical resistivity and minimized band tail states and related structural defects, resulting in improved crystallinity.