A Review on the Recent Advancements in Tin Oxide-Based Thin-Film Transistors for Large-Area Electronics

Amorphous oxide semiconductors have gained significant attention in the past few decades and have emerged as a promising material for thin-film transistors (TFTs) because they offer high carrier mobility (> 10–50 cm²/V s) and uniformity. In particular, amorphous indium-gallium-zinc-oxide (a-IGZO) has been widely employed as an active channel material in TFTs owing to its high mobility. However, indium-based TFTs suffer from stability problems under positive, negative, and illumination bias stress conditions, which limits their applications in flat-panel displays. Moreover, the limited supply of indium and growing demand for high-stability TFTs with better electrical performance has led to the introduction of tin oxide as a promising solution to replace indium in TFTs. This review provides an overview on the progress and recent developments in indium-free tin oxide-based TFTs for large-area electronics, with special emphasis on the sputtering technique. In addition, the source of the dual conductivity of tin oxide is addressed, which will be helpful in designing complementary metal oxide semiconductor devices. The instability problems and approaches to improve the electrical performance of tin oxide TFTs are also discussed.