Study on the hydrolytic property and thermal stability of LiAlO2 substrate

The hydrolytic property and thermal stability of LiAlO2 (LAO), important factors for its application, were examined by AFM and X-ray rocking curve. We found that H2O may be deleterious for LAO surface polishing when the root mean square (RMS) value is less than 1 nm. However, when the RMS value is more than 1 nm it may be useful for LAO polishing. (1 0 0)-plane LAO substrates are annealed in the range of 850∼900 °C in flux N2, slick AlN layer probably is produced on the substrate surface. M-plane GaN layer has grown on the substrate by metal–organic chemical vapor deposition (MOCVD) method. Theses results show that LiAlO2 crystal is a promising substrate of fabricating high-efficiency LEDs by MOCVD.