Post-deposition annealing and hydrogenation of hot-wire amorphous and microcrystalline silicon films

Amorphous and microcrystalline silicon films deposited by hot-wire chemical vapor deposition were submitted to thermal annealing and to RF and electron-cyclotron resonance (ECR) hydrogen plasmas. Although the transport properties of the films did not change after these post-deposition treatments, the power density of a Ar+ laser required to crystallize the amorphous silicon films was significantly lowered by the exposure of the films to a hydrogen plasma. This decrease was dependent on the type of hydrogen plasma used, being the strongest for an ECR plasma with the substrate held at a negative bias, followed by an ECR hydrogen plasma with the substrate electrode grounded, and finally by an RF hydrogen plasma.