Effects of evaporation vapor composition and post-annealing conditions on carrier density of undoped BaSi2 evaporated films

The effects of vapor composition during evaporation and post-annealing conditions on the carrier density of undoped BaSi2 films were investigated. Regardless of the vapor composition during evaporation, the carrier density after post-annealing changed in the range between 10(16) and 10(17) cm(-3) by changing the post-annealing temperature. In addition, post-annealing above 920 degrees C induced carrier type transition from n-type to ptype. The temperature at which the carrier type transition occurred was found to depend on the surface covering material during post-annealing, which implies that the carrier type transition could originate from the change of the BaSi2 film composition to Si-rich. (c) 2020 The Japan Society of Applied Physics