Polycrystalline silicon films have been deposited on glass substrates at 350 °C by radio-frequency plasma-enhanced chemical vapor deposition using a SiF4+H2 gas mixture. Crystalline fraction decreased abruptly with increasing gas flow ratio. Film structure drastically changed by increasing gas pressure from 0.4 to 2.0 Torr. At lower gas pressure, columnar crystals 30 nm in diameter grew from the glass substrates, while at higher gas pressure larger columnar crystals with a maximum diameter of approximately 100 nm grew on an amorphous Si layer approximately 170 nm thick.

This paper describes the effects of annealing on electric properties and structure of amorphous indium-tin oxide (ITO) films deposited by sputtering at room temperature and with H2O addition. The film resistivity was increased by annealing at 150–200° C; in this temperature range the growth of ITO crystallites dispersed in the amorphous ITO phase was observed. This increased resistivity was found to be due to decreases in both Hall mobility (µ H) and carrier density (n) of the films. Measurements of thermal desorption spectroscopy revealed that two different adsorption states, in terms of H2O molecules which are due to the hydrogen-bonded H2O and OH species, were formed in amorphous ITO films during film deposition and the subsequent annealing process. Factors in the decreases of µ H and n were discussed on the basis of the experimental results obtained.

Hydrogenated amorphous indium–tin–oxide (ITO) films were prepared by a sputtering method at room temperature with H2O addition. The initial stage of thermal crystallization of the amorphous films was investigated after annealing at 150 °C, just below the crystallization temperature. With increasing H2O addition, the growth of crystallites dispersed in the amorphous matrix was suppressed, while the nucleation of crystallites was sharply enhanced. The amount of bonded hydrogen increased and that of oxygen vacancies decreased at the same time, with introducing inhomogeneites in the amorphous matrix. The effect of these microstructural changes on the nucleation and growth process of crystallites embedded in the amorphous solids was discussed based on these experimental results taking into account a recently proposed theoretical prediction to describe the crystallization of disordered solids.

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Microcrystalline silicon (?c-Si) films have been prepared at 200?C by radio-frequency (rf: 13.56 MHz) plasma-enhanced chemical vapor deposition using pulsed silane flow. The crystalline fraction, X c(Raman), of ?c-Si films approximately 200 nm thick is quantitatively determined by decomposing Raman spectra into three peaks: crystalline, intermediate (small-grain-size-crystalline), and amorphous. The effects of rf power on X c(Raman) and hydrogen content, C H, have been studied. X c(Raman) increases with increasing rf power and tends to saturate; the maximum value of X c(Raman) is 71%. With increasing rf power C H decreases to a minimum value of 4.5% and then increases. Hydrogen introduction into Si films overlapped with hydrogen elimination is responsible for the increase and saturation of X c(Raman) with rf power.