Selective area growth by metal organic vapor phase epitaxy and atomic layer epitaxy using Ga2O3 as a novel mask layer

A novel technique is proposed for advanced microstructure formation using G a2O3 as a new mask material. Ga2O3 layers were prepared by RF sputtering wi th Ga2O3 powder target and patterned using photolithography. Scanning elect ron microscope (SEM) and Photoluminescence (PL) measurement findings indica te that reasonably high-quality single crystalline GaAs layers could be suc cessfully grown selectively on the unmasked region by metal organic vapor p hase epitaxy (MOVPE) and atomic layer epitaxy (ALE), The GaAs/AlGaAs quantu m structure was also fabricated by selective area MOVPE, however, at this s tage, polycrystalline AlGaAs layers formed on the mask region after the mas k removal and the regrowth of AlGaAs overlayers. The key factor in this mic rostructure fabrication process is the sensitive dependence of Ga oxide lay ers against the reactor pressure under H-2 exposure.