Tailoring oxygen vacancies in Ni-doped In 2 O 3 for improved thin-film transistor stability and performance via solution processing

Abstract Doping in thin-film transistors (TFTs) plays a crucial role in tailoring material properties to enhance device performance, making them essential for advanced electronic applications. This study explores the synthesis and characterization of TFTs fabricated using nickel (Ni)-doped indium oxide (In 2 O 3 ) via a wet-chemical approach. The presented work investigates the effect of "Ni" incorporation in In 2 O 3 on the structural and electrical transport properties of In 2 O 3 , revealing that higher "Ni" content decreases the oxygen vacancies, leading to a reduction in leakage current and a forward shift in threshold potential ( V th ). Experimental findings reveal that NiInO-based TFTs (with Ni = 0.5%) showcase enhanced electrical performance, achieving mobility of 7.54 cm 2 /(V∙s), an impressive ON/OFF current ratio of ~10 7 , a V th of 6.26 V, reduced interfacial trap states ( D it ) of 8.23 × 10 12 cm −2 and enhanced biased stress stability. The efficacy of "Ni" incorporation is attributed to the upgraded Lewis acidity, stable Ni−O bond strength, and small ionic radius of Ni. Negative bias illumination stability (NBIS) measurements further indicate that device stability diminishes with shorter light wavelengths, likely due to the activation of oxygen vacancies. These findings validate the solution-processed techniques' potential for future large-scale, low-cost, energy-efficient, and high-performance electronics.