In situ boron-doped polycrystalline silicon films prepared by a novel low-pressure chemical vapour deposition method using a gas system

Abstract

In situ boron-doped silicon films were deposited by a novel LPCVD process in the gas system. A high deposition rate and good thickness uniformity of films were obtained by the process. The silicon film annealed becomes polycrystalline with strong (111) texture. The polycrystalline silicon films annealed at were made of small grains. A uniform distribution of boron concentration was obtained in the silicon films and penetration of boron into the silicon substrate through the layer was not observed. The resistivity of the boron-doped silicon films was dependent on the annealing temperature and time and the minimum value of the resistivity was . Furthermore, good breakdown characteristics were achieved and the average breakdown field intensity was . This process provides a reliable gate deposition process for a sub-micrometre CMOS device with a surface channel.