P-channel thin film transistor of microcrystalline silicon directly deposited at 320/spl deg/C

We report the first p-channel thin-film transistor made in directly-deposited microcrystalline silicon (/spl mu/c-Si). The channel silicon is made by plasma-enhanced vapor deposition (PECVD) in a process similar to the deposition of hydrogenated amorphous silicon (a-Si:H). The deposition temperature for the /spl mu/c-Si is 320 /spl deg/C and the highest post-deposition TFT process temperature is 280 /spl deg/C. The p-channel TFT is made possible by the low-temperature deposition of /spl mu/c-Si with near-intrinsic properties. Because making p-channel TFTs of a-Si:H has not been possible to date, the p-channel /spl mu/c-Si TFT represents a breakthrough in low temperature Si TFT technology.