Simple route for SrTiO3 epitaxy on GaAs

Combining functional oxides with III–V semiconductors holds significant prospects for novel electronic and optoelectronic devices. However, oxide epitaxy on III–V semiconductors remains challenging due to chemical instabilities and lattice mismatch. Years of development yielded a solution to these challenges, enabling previous works to demonstrate high quality SrTiO3/GaAs interfaces. Prior successes have relied on a well-rationalized and rigorously developed multistep growth procedure, considered necessary for passivating the GaAs surface. Here, we consider a provocative question: is this elaborate procedure necessary? We compare the growth results of a new and simple method for SrTiO3/GaAs epitaxy versus the “classic” method developed before and compare the resulting film properties. We demonstrate how both growth methods can produce a comparable and high quality microstructure. We further discuss growth variations in the process that are unrelated to the choice of the growth method. Simplifying the growth procedure can reduce its sensitivity to process details, thereby increasing consistency and uniformity. It can further increase the growth throughput and productivity toward scalable production. With these advantages, the new method can push oxide epitaxy on GaAs closer toward practical applications, unlocking the potential of functional oxides in novel devices.