Effect of the deposition process on the crystallization of polycrystalline silicon thin film on glass substrate

A polycrystalline Si (poly-Si) film was successfully deposited directly at a low temperature of 430 °C on a glass substrate using a seed layer method, in which crystallization of the Si film was stimulated by the polycrystalline yttria-stabilized zirconia (YSZ) seed layer. However, the deposited Si film suffered from surface roughness (RMS: 3.21 nm) and zirconium diffusion from the Si/YSZ interface. To solve these problems, crystallization of the Si film deposited on the YSZ layer by the solid-phase crystallization (SPC) method was proposed. It was found that the Si film on the YSZ layer crystallized with a relatively high crystalline fraction compared to that on glass substrate (Si/YSZ: 61.8%, Si/glass: 11.4%) after being annealed at 535 °C for 60 min, which showed that the YSZ seed layer is also effective for the SPC method. The Si film by SPC method also has smoother surface than the directly-deposited Si film.