Al-2 % Si Induced Crystallization of Amorphous Silicon

Al-2% Si induced crystallization of amorphous silicon (a-Si) is investigated. The 2% Si is found to enhance the crystallization process, thereby reducing the initial crystallization temperature by ∼50°C. The enhancement is attributed to the presence of Si precipitates in the Al-2% Si film, which act as nucleation sites for Si grain growth. As with the Al/a-Si system, adjacent Al-2% Si and a-Si films undergo a layer exchange during isothermal annealing, resulting in a continuous polycrystalline silicon film with good physical and electrical properties. The activation energy for the process is 0.97 ± 0.09 eV, indicating that the crystallization is a diffusion-limited process.