Doping and electrical properties of amorphous silicon carbon nitride films

Abstract

Electrical properties and annealing behaviour of undoped and doped amorphous silicon carbon nitride (a-SiC x N y ) thin films, deposited by ion beam sputtering techniques, have been studied. Doping of the a-SiC x N y thin films with magnesium (Mg), and phosphorous (P) was carried out by ion implantation techniques, and subsequent annealing effect on the electrical conductivity (σ) and activation energies for electrical conduction have been reported. It was found that the undoped films were insulating with electrical conductivities in the range of 10 −6–10 −8 S/cm. Annealing of these films at high temperatures aided in some structural relaxation and hence an increase in σ by several orders of magnitude without showing any indications for crystallization. Suitable doping (Mg) of the films resulted in increased σ, and in some cases of low phosphorous doping a decrease in σ was also found which indicated that the films may be intrinsically p-type.