MICROSTRUCTURES AND CARRIER TRANSPORT BEHAVIORS OF NANOCRYSTALLINE SILICON THIN FILMS

Hydrogenated amorphous Si thin films were prepared by plasma-enhanced chemical vapor deposition technique. As-deposited samples were thermally annealed above 80 degrees C. to obtain nanocrystalline Si and the microstructures and carrier transport behaviors were evaluated. It was found that the crystallization of amorphous silicon can be improved by increasing the annealing temperature. Temperature-dependent Hall measurements were performed and the Hall mobility of the thermally annealed sample is 0.86 cm(2)/V.s, which is one order magnitude larger than that of as-deposited amorphous Si film. The nanocrystalline Si films exhibit a thermally activated electrical transport above room temperature.