The formation and annihilation of O-related new donors in ribbon-growth-on-substrate material was studied. Due to high concentrations of O and C which were introduced during growth, the generation of new donors could not be entirely avoided during processing (such as P diffusion) at temperatures above 550C. The energy levels of new donors were continuously distributed in the band-gap and acted as recombination centers. The total new donor concentration, of up to 5 x 1015/cm3, could be sharply reduced if P diffusion was performed at temperatures above 950C and was followed by hydrogenation.

Formation and annihilation of new donors in ribbon growth on substrate silicon D.Karg, A.Voigt, J.Krinke, C.Hässler, H.U.Höfs, G.Pensl, M.Schulz, H.P.Strunk: Solid State Phenomena, 1999, 67-68, 33-8