Optical probing of low-pressure solution grown GaN crystal properties

Efficient Incorporation of Mg in Solution Grown GaN Crystals

“…10) Previous studies of self-nucleated crystals indicate that these crystals have an X-ray rocking curve full width at half maximum (FWHM) similar to that of Ammonothermal crystals, record small FWHM of the first-order allowed optical phonons, and relatively low room temperature (RT) free carrier concentrations. 11,12) The samples used in this experiment were grown in a custom-designed reactor incorporated in a vertical tube furnace. A multi-component solvent was employed to dissolve the GaN source and subsequently grow single crystal GaN from the solution.…”

Classification of Semiconductors Using Photoluminescence Spectroscopy and Machine Learning

“…9 GaN typically has a peak near 365 nm due to a band-to-band transition, and a small peak near 382 nm due to recombination of an electron in the conduction band with a hole bound to an acceptor. 10 Two broad yellow peaks near 482 nm and 525 nm caused by carbon-related defects are also observed. 11 The main peak of CdS, WS 2 , 13 and CsPbBr 3 , 14 at 508 nm, 630 nm, and 523 nm, respectively, is due to exciton recombination.…”

“…Figure 6. PL spectra of GaN from Balkas et al,26 Chen et al, Chakrapani et al,28 and Freitas et al10 …”

Liquid-Phase Epitaxy

“…Kawamura et al [559,560] describe a two-stage dislocation reduction process in Na flux solution growth of 2-mm thick GaN layers, yielding dislocation densities as low as 10 2 cm -2 . Freitas et al [561] concluded that reduced residual impurity levels could be achieved in solution growth of GaN from Ga-Li melts using nitrogen pressures of 0.23-0.25 MPa and growth temperatures of 760-800 C. Masumoto et al [562] studied the effect of Ca and Li additives to Na melts in GaN LPE on GaN/sapphire substrates with growth temperatures of 850-890 C, indicating improved quality of crystal transparency and surface smoothness. Further, Ca, Li, and oxygen impurities in GaN were decreased by using higher growth temperatures.…”