a-Si/c-Si INTERFACES: THE EFFECT OF ANNEALING AND FILM THICKNESS

Very thin intrinsic amorphous silicon films (<10 nm) are used for passivation studies of crystalline silicon. In this paper, a-Si:H layers are subjected to a variety of post-treatments. A hydrogen plasma treatment crystallizes the thin film almost instantaneously, significantly reducing the effective lifetime. Anneals in different atmospheres typically show similar results, which are highly dependent on the initial state of the a-Si/c-Si interface. Data will be discussed and conditions compared of thin intrinsic a-Si:H films that show changes in effective lifetime due to annealing. Films with initial low effective lifetimes can result in low or high lifetimes after annealing, while the opposite is also possible; films with high initial lifetime can result in low or high lifetime after annealing. Lastly, a minimum thickness of the intrinsic layer is needed for annealing to demonstrate a positive effect on the effective lifetime.