EFFECT OF HYDROGEN PASSIVATION ON ELECTRICAL TRANSPORT IN POLYCRYSTALLINE SILICON

Hydrogen passivation of grain boundaries in polycrystalline silicon is shown to improve the efficiencies of devices fabricated from these materials. We have carried out hydrogen plasma passivation of polycrystalline silicon in RF discharge and have studied the variation in room temperature resistivity of the polysilicon wafer after H plasma treatment. In order to study intergrain changes in the polysilicon wafer after optimum H plasma treatment, we have carried out J(V,T) measurement in the temperature range 130 to 330 K. It is shown that after optimum hydrogenation, the temperature range over which thermionic emission occurs extrapolates to a much lower temperature value which is due to reduction of the grain boundary potential barrier after H passivation. © 1990.