Growth, optical, and electrical properties of silicon films produced by the metal-induced crystallization process

Abstract

Amorphous Si (a-Si) and Ni films were deposited by electron beam evaporation on to borosilicate glass (BSG) substrate maintained at ambient temperature. The BSG/a-Si/Ni stack was subjected to post deposition annealing in air at various temperatures from 200 to 500 °C for 1 h. Electron diffraction was employed to characterize the crystallographic phases appearing on the stacks that were depending on initial conditions. Clear evidence of the formation of hexagonal Si and fcc NiSi 2 was shown by TEM. In parallel, an increase of refraction index was observed. Electrical resistivity measurements showed that resistance is of the order of kilo ohms in the as-deposited films, increasing sharply to giga ohms in films annealed at T higher than 300 °C. A large band gap of 2.23 eV which is the combined contribution from a-Si, wurtzite-Si, and Ni silicide phases, is observed. © Springer Science+Business Media B.V. 2011.