Abstract-In this paper, we successfully applied the PECVD method to deposit nanocrystalline
silicon films (nc - Si: H) and determined the microstructure with HREM and STM
technology. The nc - Si: Hfilms consist of a large number of micrograins and interfaces. For this
man-made film material with special structure, we studied the piezo- resistance effect and
hydrogen content, which varied with the microstructure of the films. We suggest that the unique
structure of nc - Si:Hfilms is the main cause of largerpiezo- resistance effect and higher hydrogen
content in the films.