Recent progress and perspectives on atomic‐layer‐deposited semiconducting oxides for transistor applications

Abstract This paper reviews recent developments in the fabrication of high‐performance n ‐channel metal‐oxide thin‐film transistors (TFTs) through atomic‐layer deposition (ALD), which are now attracting attention due to their potential for use in augmented and virtual reality, ultra‐high‐definition organic light‐emitting diodes, and flexible electronics. Recent trends in research on TFT backplanes for display applications are provided in the introduction. In the main section, ALD‐derived n‐type oxides serving as active layers are classified into binary, ternary, and quaternary systems, and recent developments and critical issues in n ‐channel oxide TFTs are described. The performance of n ‐channel oxide TFTs can be boosted through advanced architectures, including stacked heterojunction channels using two‐dimensional electron gases, and the introduction of high‐ k dielectric such as ALD‐derived hafnium oxide, which is highlighted in this review. Finally, progress in p ‐channel ALD‐derived oxide TFTs is briefly addressed with respect to complementary metal–oxide‐semiconductor applications.