Amorphous LaZnSnO thin films by a combustion solution process and application in thin film transistors

Amorphous LaZnSnO thin films with different La doping concentration are prepared by a combustion solution process and the electrical performances of thin film transistors (TFTs) are investigated. The influence of La content on the structure, oxygen vacancies, optical and electrical performance of LaZnSnO thin films are investigated. At an appropriate amount of La doping (15 mol.%), LaZnSnO-TFT shows a superior electrical performance including a mobility of 4.2 cm2/V s, a subthreshold swing of 0.50 V/decade and an on/off current ratio of 1.9 × 107. The high performance LaZnSnO-TFT is attributed to the better interface between SiO2 and LaZnSnO channel layer and the suppression of oxygen vacancies by optimizing La content. It suggests that La doping can be a useful technique for fabricating high performance solution-processed oxide TFTs.