Selenium-alloyed tellurium oxide for amorphous p-channel transistors

Abstract Compared to polycrystalline semiconductors, amorphous semiconductors offer inherent cost-effective, simple and uniform manufacturing. Traditional amorphous hydrogenated Si falls short in electrical properties, necessitating the exploration of new materials. The creation of high-mobility amorphous n-type metal oxides, such as a-InGaZnO (ref. 1 ), and their integration into thin-film transistors (TFTs) have propelled advancements in modern large-area electronics and new-generation displays 2–8 . However, finding comparable p-type counterparts poses notable challenges, impeding the progress of complementary metal–oxide–semiconductor technology and integrated circuits 9–11 . Here we introduce a pioneering design strategy for amorphous p-type semiconductors, incorporating high-mobility tellurium within an amorphous tellurium suboxide matrix, and demonstrate its use in high-performance, stable p-channel TFTs and complementary circuits. Theoretical analysis unveils a delocalized valence band from tellurium 5 p bands with shallow acceptor states, enabling excess hole doping and transport. Selenium alloying suppresses hole concentrations and facilitates the p- orbital connectivity, realizing high-performance p-channel TFTs with an average field-effect hole mobility of around 15 cm 2 V −1 s −1 and on/off current ratios of 10 6 –10 7 , along with wafer-scale uniformity and long-term stabilities under bias stress and ambient ageing. This study represents a crucial stride towards establishing commercially viable amorphous p-channel TFT technology and complementary electronics in a low-cost and industry-compatible manner.