High-Temperature Crystallization of Amorphous Silicon on a Molybdenum Substrate

Polycrystalline silicon is a widely studied material for use in high quality thin film transistor active layer. High temperature processes cannot be used for glass substrates because of its low softening temperature below 450°C. However, high temperature crystallization has the advantage of getting high crystalline volume fractions. In this paper, the amorphous silicon deposited by hot-wire chemical vapor deposition was crystallized at a temperature between 750°C to 1050°C within 2 min induced by a high current over 48A between electrodes. The film grown at a crystallization temperature of 850°C for 2 min exhibits a crystalline volume fraction of 80.9%, a preferential growth of (220) orientation, and an activation energy of 0.22eV. Moreover, high temperature polycrystalline silicon using a Mo substrate has special advantages of crystallization such as high crystallinity, simple, low cost and high temperature endurance.