Oxide-semiconductor interface roughness and electrical properties of polycrystalline silicon thin-film transistors

Abstract
Polycrystalline silicon thin-film transistors (TFTs) have been fabricated with a smooth oxide-semiconductor interface. Device characteristics are found to be improved with the interface smoothness. The channel mobility is especially improved to about 2 times larger than that of conventional poly-Si TFTs. The topography of the oxide-semiconductor interface was analyzed using nanometer resolution atomic force microscopy. The roughness of the oxide-semiconductor interface and the electrical properties of poly-Si TFTs are found to have a strong relationship.l