The properties of SiNx films prepared by catalytic chemical vapor deposition (Cat-CVD) on various gate-metals were studied for application of bottom-gate thin-film transistors (BG-TFTs). Additionally, the gate-insulating properties after rapid thermal annealing (RTA) were investigated for the fabrication of polycrystalline silicon (poly-Si) TFTs by simple RTA of amorphous silicon (a-Si:H) BG-TFTs. It was found that Cat-CVD SiNx on metals can be used as gate-insulating films of a-Si:H BG-TFTs and that the films can also be used even after RTA at 800 degrees C, when the surface of such metals is slightly oxidized. (c) 2005 Elsevier B.V. All rights reserved.