Ternary Al2xIn2−2xO3 films with tunable optical band gap prepared on YSZ (1 0 0) substrates by metal organic chemical vapor deposition

• Ternary Al2xIn2−2xO3 films were prepared on the YSZ (1 0 0) substrates by MOCVD at 700 °C.
• The lowest resistivity of 4.84 × 10−3 Ω cm was obtained for the sample with x = 0.2.
• Excellent optical transparency in the UV and visible wavelength regions was achieved.
• Tunable optical band gap from 3.67 to 4.73 eV was obtained.

The ternary Al2xIn2−2xO3 films with different Al contents of x [Al/(Al + In) atomic ratio] have been fabricated on the Y-stabilized ZrO2 (YSZ) (1 0 0) substrates by the metal organic chemical vapor deposition (MOCVD) method at 700 °C. The influence of various Al contents (x = 0.1–0.9) on the structural, electrical and optical properties of the films have been investigated. Structural analyses revealed a phase transition from the bixbyite In2O3 structure with a single orientation along (1 0 0) to the amorphous structure as the Al content increases from 10% to 90%. The lowest resistivity of 4.84 × 10−3 Ω cm with a carrier concentration of 1.1 × 1020 cm−3 and a Hall mobility of 11.74 cm2 V−1 s−1 were obtained for the sample with x = 0.2. The average transmittances for the Al2xIn2−2xO3 films in the visible range were all over 77% and the optical band gap of the films could be modulated from 3.67 to 4.73 eV.