Low-Temperature and High-Quality Growth of BiOSe Layered Semiconductors Cracking Metal-Organic Chemical Vapor Deposition.

Ternary metal-oxy-chalcogenides are emerging as next-generation layered semiconductors beyond binary metal-chalcogenides (, MoS). Among ternary metal-oxy-chalcogenides, especially BiOSe has been demonstrated in field-effect transistors and photodetectors, exhibiting ultrahigh performance with robust air stability. The growth method for BiOSe that has been reported so far is a powder sublimation based chemical vapor deposition. The first step for pursuing the practical application of BiOSe as a semiconductor material is developing a gas-phase growth process. Here, we report a cracking metal-organic chemical vapor deposition (c-MOCVD) for the gas-phase growth of BiOSe. The resulting BiOSe films at very low growth temperature (∼300 °C) show single-crystalline quality. By taking advantage of the gas-phase growth, the precise phase control was demonstrated by modulating the partial pressure of each precursor. In addition, c-MOCVD-grown BiOSe exhibits outstanding electrical and optoelectronic performance at room temperature without passivation, including maximum electron mobility of 127 cm/(V·s) and photoresponsivity of 45134 A/W.