Properties of Polycrystalline Silicon Deposited on Silicon Nitride Layers

The properties of polycrystalline silicon deposited on silicon nitride by the thermal decomposition of silane were investigated. It was found that the deposition temperature of the silicon and the thickness of the layer had a marked effect on the diffusion characteristics. The diffusion profile of boron in the silicon layer was determined and the diffusion constant of boron into silicon at 1050°C was found to be . This compares with oriented single‐crystal silicon under the same conditions. The ratio of Hall mobility of holes in polycrystalline silicon to the mobility in single‐crystal silicon was found to be 0.57. No significant difference was found between the oxidation rate of polycrystalline‐single and (111) oriented single‐crystal silicon.