Microstructures and characteristics of nano-size crystalline silicon films

Microstructures and characteristics of nano-size hydrogenated crystalline silicon films (nc-Si:H) have been studied by high-resolution electron microscopy (HREM), X-ray diffraction patterns and Raman spectroscopy. The microcrystalline grains in nc-Si:H films are about 3-5 nm in size and are separated by different characteristic boundaries. The volume fraction of the crystalline component is about 46%. Microdefects in nanocrystalline grains were also found. The electrical conductivities of the films were found by measurement to be about 10-3-10-2 ( Omega cm)-1. Analysis of the experimental results shows that the nano-size hydrogenated crystalline silicon films are in good agreement with the international definition of nanocrystalline material.