Selenium-alloyed tellurium oxide for amorphous p-channel transistors

Abstract

<jats:title>Abstract</jats:title><jats:p>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. <jats:sup>1</jats:sup>), and their integration into thin-film transistors (TFTs) have propelled advancements in modern large-area electronics and new-generation displays<jats:sup>2–8</jats:sup>. However, finding comparable p-type counterparts poses notable challenges, impeding the progress of complementary metal–oxide–semiconductor technology and integrated circuits<jats:sup>9–11</jats:sup>. 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<jats:italic>p</jats:italic> bands with shallow acceptor states, enabling excess hole doping and transport. Selenium alloying suppresses hole concentrations and facilitates the <jats:italic>p-</jats:italic>orbital connectivity, realizing high-performance p-channel TFTs with an average field-effect hole mobility of around 15 cm<jats:sup>2</jats:sup> V<jats:sup>−1</jats:sup> s<jats:sup>−1</jats:sup> and on/off current ratios of 10<jats:sup>6</jats:sup>–10<jats:sup>7</jats:sup>, 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.</jats:p>