Kinetics of electric-field-enhanced crystallization of amorphous silicon in contact with Ni catalyst

Electric-field-enhanced crystallization of hydrogenated amorphous silicon in contact with nickel catalyst (Ni/a-Si:H) has been investigated. In order to elucidate the crystallization kinetics quantitatively, in situ conductivity measurement was used. With the change of Ni dose (4×1013∼1.3×1015 cm−2) and annealing temperature (550∼500 °C), crystallization rate varied drastically at the electric field of 33 V cm−1. The activation energy for the crystallization was found to be strongly dependent on the Ni dose, 85 kJ mol−1 for 1.3×1015 Ni cm−2, 243 kJ mol−1 for 6×1014 Ni cm−2, and 276 kJ mol−1 for 4×1013 Ni cm−2, respectively. The polycrystalline silicon films were composed of needle-like crystallites of ∼5 μm (long axis) and their thin-film transistors (TFTs) showed field effect mobility of 43 cm2 V−1 s−1.