Effect of Rapid Thermal Annealing Condition on the Structure and Conductivity Properties of Polycrystalline Silicon Films on Glass

Abstract

The effect of rapid thermal annealing (RTA) temperature (700~1200 °C) and time (1~8 min) on the structure and conductivity properties of polycrystalline silicon (Si) films on glass, grown by RTA crystallization of magnetron sputtering (MS) deposited amorphous Si (a-Si) films, was investigated by means of X-ray diffraction (XRD) and UV reflectance. It was observed the critical temperature for crystallizing a-Si films was ~750 °C and ~700 °C based on XRD and reflectance measurements, respectively. As soon as RTA temperature reached and exceeded the critical value, the structural property of polycrystalline Si films increased with RTA temperature or time. The above results were related to the thermal and photon effects induced by RTA. Moreover, it was revealed that the resistivity of polycrystalline Si films decreased with RTA temperature, however, even the resistivity of the polycrystalline Si films annealed at 1200 °C was 2 orders of magnitude higher than that of Si target, attributed to the carrier scattering by grain boundaries or defects. The polycrystalline Si films on glass fabricated by MS deposition combined with RTA crystallization may endow them with great application potentials in Si thin-film solar cells.