Abstract: Ga2（1-x）In2xO3（x=01—09） thin films were prepared on α-Al2O3 （0001） substrates by metalorganic chemical vapor deposition （MOCVD）. The structure， the optical and electrical properties as well as the effect of annealing on the properties of the films were investigated in detail. The results indicate that the film deposited with composition x=02 was polycrystalline with β-Ga2O3 structure， the film with x=05 was amorphous and transformed into body-centered cubic （bcc） structure of In2O3 with a preferred orientation of （222） after annealing. For x=08， the obtained film showed bcc structure of In2O3 and the crystalinity was improved after annealing treatment. The average transmittance for the films in the visible range was over 85%. The band-gap of the Ga2（1-x）In2xO3 films can be suitably tuned from 376 to 443 eV by controlling the gallium content and it is increased obviously by annealing.

Keywords: 
• metalorganic chemical vapor deposition（MOCVD） /
• Ga2（1-x）In2x　O3 thin films /
• α-Al2O3 substrates /
• annealing