Structural, optical and electrical properties of Al–In–Sn–O (AITO) films fabricated via MOCVD technique

Abstract

Abstract Al–In–Sn–O (AITO) films were grown onto MgO (100) substrates via metal organic chemical vapor deposition (MOCVD) technique. XRD analyses revealed that as the Sn concentration increased from 0% to 24%, the AITO film turned from amorphous structure to monophasic crystalline state, and then degenerated to miscible crystalline structure. The resistivity of the film was reduced by two orders of magnitude by adding tin element with the lowest resistivity of 1.32 × 10−3 Ω cm and the highest mobility of 18.5 cm2 V−1s−1 obtained for the AITO film with 21% tin content. The average transmittance of the AITO samples in the visible wavelength was over 83%. The optical band gap decreased from 5.42 to 4.18 eV as the Sn content increased from 0% to 24%. The AITO with both wider band gap and better conductivity is a promising heterojunctions and quantum wells material.