A study of the effects of thermal oxidation and hydrogen passivation on CVD polysilicon pin solar cells using DLTS

The effects of multiple oxidations of a thin polycrystalline silicon seed layer on the structure and electronic properties of a subsequently grown thick polysilicon films are investigated. A direct correlation is observed between the number of initial thermal oxidations of the seed layer, the cell efficiency, and the relative concentration of majority carrier traps. During hydrogenation, the majority carrier trap disappears and the minority carrier capture cross-section decreases from 3*10/sup -13/ to 8*10/sup -15//cm/sup 2/. The activation energy of this trap is 0.45 eV before hydrogenation, decreases to 0.35 eV after 17 min of hydrogenation, and increases to 0.42 eV after 60 min.<
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