Near band‐edge 3.357 eV emission of Ga‐face (0001) GaN grown by ammonothermal method

Abstract

Excitonic emission was observed at 3.357 eV by photoluminescence only from the (0001) Ga‐face of GaN grown by an ammonothermal method. The emission intensity varied over the crystal surface. The temperature dependence of the emission intensity is similar to that of excitons bound to neutral donors for hexagonal (2H) GaN. The origin of the emission is discussed. (© 2008 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

Physico-chemical features of the acid ammonothermal growth of GaN

“…The latter is of relatively lower intensity for the ammonothermal GaN sample Exp. 106-1 than for the HVPE-GaN and was recently speculated due to a defect in the stacking order of the GaN crystal structure [10]. Hence, this hints to the high-structural order of the ammonothermal sample, quite in similarity to the HVPE standard sample.…”

Surface changes by GaN photoelectrochemical treatment using various electrolytes with and without C2H5OH

“…The Y7 peak was reported to appear with Y4 peak [7]. The origin of the Y4 peak was discussed and assumed to the D 0 X emission of a polytype GaN [9]. From these results, the Y2 and Y6b peaks of PL observed from the surface treated using Na 2 SO 4 without C 2 H 5 OH are probably related to Ga oxide.…”

Reviewing recent developments in the acid ammonothermal crystal growth of gallium nitride

“…PL measurements were made to evaluate the optical quality of some of the ammonothermal GaN samples and were recently presented in greater detail in Refs. [8,24,25]. A general observation by PL is that the GaN nucleated on the N-polar face seems of higher optical quality than the GaN nucleated on the Ga-polar face.…”