Experimental and theoretical evidence for hydrogen doping in polymer solution-processed indium gallium oxide
Wei Huang, Po‐Hsiu Chien, K. R. McMillen, Sawankumar V. Patel, Joshua Tedesco, Li Zeng, S. Mukherjee, Binghao Wang, Yao Chen, Gang Wang, Yang Wang, Yanshan Gao, Michael J. Bedzyk, Dean M. DeLongchamp, Yan‐Yan Hu, Julia E. Medvedeva, Tobin J. Marks, Antonio Facchetti
Abstract
Significance Solution processing of high-performance, high-Ga-content IGZO thin-film transistors (TFTs)—or compositionally simpler and, hence, technologically more desirable indium gallium oxide (IGO) TFTs—remains challenging and an impediment to manufacturing low-temperature, solution-processed metal oxide electronics. Here, the performance of aqueous solution-processed IGO TFTs is greatly enhanced with polyvinyl alcohol in the precursor solution, yielding a >70-fold increase in electron mobility. By achieving optimal H doping and conversion from six- to four-coordinate Ga, PVA addition suppresses deep trap defect localization. This result not only offers a route to high-performance, ultra-stable metal oxide semiconductor electronics with simple binary compositions, but also provides powerful tools to probe H locations in amorphous metal oxides via a combination of experimental and theoretical approaches.