Passivation properties of a-Si/sub 1-x/N/sub x/:H/SiO/sub 2/ double-layer structures

Investigation of the improvement of effective lifetime (/spl gamma/) induced by using a-Si/sub 1-x/N/sub X/:H/SiO/sub 2/ double-layer passivation structures showed that the T values obtained were higher than those obtained when using a-Si/sub 1-x/N/sub x/:H or SiO/sub 2/ monolayer passivation. Furthermore, the /spl gamma/ of a-Si/sub 1-x/N/sub x/:H/SiO/sub 2/ structures was greatly increased with increase of the bias light intensity. This effect was almost independent of the (x/1-x) ratio of the a-Si/sub 1-x/N/sub X/:H layer, and it is therefore possible to control the refractive index of a-Si/sub 1-x/N/sub x/:H layers independently while keeping good passivation effect.