The highly oriented (001) GaSe film on c-cut sapphire (0001) was successfully fabricated by pulsed laser deposition. As growth temperature decreases from 550°C to 375°C, the structure of films changes from cubic zinc-blende Ga2Se3 phase to GaSe phase. The growth temperature of the critical transition from Ga2Se3 phase to GaSe phase is around 500°C. From atomic force microscope (AFM) results, it is observed that the growth process of GaSe film is in the manner of layer plus island growth. Besides, the optimal growth conditions of as-grown GaSe film were obtained at a substrate temperature of 400°C and laser energy density of 11.7 J/cm2. When the thickness of films goes beyond 800 Å, the stress will be released and the thickness of 1200 Å results in an optimal GaSe film. Furthermore, the indirect bound exciton emission and the recombination via impurity levels or structural defects were observed from low-temperature photoluminescence measurement.
|Number of pages||5|
|Journal||Japanese Journal of Applied Physics, Part 1: Regular Papers and Short Notes and Review Papers|
|Publication status||Published - 2003 Aug|
All Science Journal Classification (ASJC) codes
- Physics and Astronomy(all)