Study on growth and properties of novel gamma-LiAlO_2 substrate

摘要

Transparent gamma-LiAIO_2 single crystal has been grown by Temperature Gradient technique. The surface of the wafer annealed in O_2-atmosphere at 1100 deg C for 70 h became opaque and Li-poor phase (LiAI_5O_8); while, that annealed in Li-rich atmosphere kept transparent and smooth. The full-width at half maximum value dropped to 30 arcsecs when the wafer was annealed in Li-rich atmosphere. That annealed in O_2-atmosphere increased to 78 arcsec. Compared with absorption spectra, we can conclude that the 196 nm absorption peak was caused by Li vacancies and the 736 nm peak was caused by O vacancies.