Improved electrical and optical properties in epitaxial Cd₂SnO₄ films

Abstract

Epitaxial Cd 2 SnO 4 films were fabricated on MgO(00l) single crystalline substrates by pulsed laser deposition technique at various substrate temperatures and growth oxygen pressures. The microstructure, transport, and optical properties of the films were studied in detail. High-resolution X-ray diffraction and high-resolution transmission electron microscopy results demonstrate that all the Cd 2 SnO 4 films are grown epitaxially on MgO(00l) substrates. Atomic force microscope images indicate that the films have smooth surface morphologies. Hall-effect measurements reveal that the epitaxial film grown at 680• C and 40 Pa presents the minimum resistivity value of 0.61 mΩcm and maximal Hall mobility of 32.87 cm 2 V −1 s −1 . The metal-semiconductor transitions of Cd 2 SnO 4 films were observed and explained by competitive effects of two conductive mechanisms. The optical transmittance of the Cd 2 SnO 4 films is higher than 75% in the visible and near-infrared range, and the optical bandgap was determined to be about 3.09 eV for the film grown at optimal condition. The band structure and density of states of the Cd 2 SnO 4 were calculated by the density functional theory.

Influence of vacancies on the optical and electronic properties of the rhombohedral In2O3 oxide

“…Metal oxides' semiconductors are recognized as the potential advanced functional materials due to the wider band gap, low cost, and chemical stability. [1][2][3][4][5][6][7] Among these oxides, indium oxide (In 2 O 3 ) which has excellent electronic, optical, and physical properties, is used in semiconductors, gas sensors, photo catalysts, and energy system. [8][9][10] As a semiconductor material, In 2 O 3 oxide is a typical n-type semiconductor with the wide band gap.…”