Structural and optoelectronic properties of single crystalline SnO2:Ga films deposited on α-Al2O3 (0001) by MOCVD

摘要

12% Gallium-doped tin oxide (SnO2:Ga) single crystalline films have been prepared on α-Al2O3 (0001) substrates by the metalorganic chemical vapor deposition (MOCVD) method. The grown temperatures were varied from 400 to 600℃. According to XRD patterns, the film deposited at 500℃ has the best single crystalline structure. Subsequently, 3 to 15% doped films were fabricated at 500℃ using the same method, except that Gallium organometallic (OM) source was injected in pulsed-mode for the 3, 5 and 10% -doped films. Then, structural and optoelectronic properties of the films were investigated in detail. The obtained films all have the rutile structure of pure SnO2. Film with resistivity of 1.09×10-2Ω cm, carrier concentration of 8.86×1019cm-3 and Hall mobility of 6.49cm2 v-1 s-1 was obtained at 5% of Ga concentration. The average transmittance for the SnO2:Ga films in the visible range were over 90%.