Reduction of defects of polycrystalline silicon thin films by heat treatment with high-pressure H2O vapor

An improvement of electrical properties of pulsed laser crystalllized silicon films was achieved by simple heat treatment with high-pressure H2O vapor. The electrical conductivity of 7.4×1017 cm−3 phosphorus-doped 50-nm-thick pulsed laser crystallized silicon films was markedly increased from 1.6×10−5 S/cm (as crystallized) to 2 S/cm by heat treatment at 270°C for 3 h with 1.25×106 Pa H2O vapor because of reduction of density of defect states localized at grain boundaries. Spin density was reduced from 1.7×1018 cm−3 (as crystallized) to 1.2×1017 cm−3 by heat treatment at 310°C for 3 h with 1.25×106 Pa H2O vapor.