Transparent conductive SnO2 thin films via resonant Ta doping

Transparent conductive oxide (TCO) thin films are highly desired as electrodes for modern flat-panel displays and solar cells. Alternative indium-free TCO materials needed, because of the scarcity high price indium. Based on mechanism resonant doping, Ta has been identified an effective dopant SnO2 to achieve transparent TCO. In this work, we fabricated a series Ta-doped (Sn1−xTaxO2, x = 0.001, 0.01, 0.02, 0.03) with conductivity optical transparency via low-cost sol-gel spin coating method. The Sn0.98Ta0.02O2 film achieves highest electrical 855 S cm−1 carrier concentration 2.3 × 1020 cm−3 mobility 23 cm2 V−1 s−1. exhibit very 89.5% in visible light region. High-resolution X-ray photoemission spectroscopy were combined gain insights into electronic structure Sn1−xTaxO2 films. bandgaps increased from 3.96 eV undoped 4.24 due occupation bottom conduction band by free electrons, i.e., Burstein-Moss effect. Interestingly, bandgap shrinkage is also directly observed renormalization arising many-body interactions. double guarantee growth method provide new platform optoelectronic cell applications.