Preparation and Electrical Property of Mg2Si Thin Film by Pulsed Laser Deposition

Abstract

Mg2Si thin film on Si(100) substrate was obtained by pulsed laser deposition. Effects of the annealing procedure on the growth of Mg2Si film were discussed. X-ray, atomic force microscopy (AFM) and field-emission scanning electron microscopy (FESEM) were applied for the phase and microstructure of the obtained Mg2Si film. The results revealed that the annealing procedure was very important for the crystallization of Mg2Si thin film. The Ar partial pressure of 10Pa, temperature of 500°C and time of 30min for annealing were the optimal annealing parameters for Mg2Si thin film formation. Furthermore, electrical properties of the obtained Mg2Si thin film were detected. The results showed that the maximal resistivity of Mg2Si thin film was 7Ω·cm within the temperature range of 110~230°C. And the resistivity gradually decreased with the increase of temperature, which was the characteristic behaviour of a semiconductor. Carrier concentration of the film was negative in the temperature range of testing, showing Mg2Si thin film as n-type semiconductor.