High quality GaN epilayers grown on carbon nanotube patterned sapphire substrate by metal–organic vapor phase epitaxy

Efficient stress-relaxation in InGaN/GaN light-emitting diodes using carbon nanotubes

“…It has been shown that growth of GaN on nano-and micro-scale masks including multi-walled CNTs induces formation of air voids at the interface. 20,28,34 However, both the TEM and FESEM (Fig. S1 in the ESI †) images did not reveal formation of any such air voids in our samples.…”

“…Unlike graphene, which requires a transfer step, the CNTs can be readily assembled on to target substrates by a simple spin coating process and the resulting nanoscale morphology can act as a natural source of nucleation for ELO to occur. 28 Specifically, although both SWCNTs and graphene have unique chemical properties, the former is more advantageous as a mask for hetero-epitaxy of GaN that their dense arrangement could provide nanoscale gaps which are highly required for efficient defect or stress relaxation. On the other hand, achieving such kind of nanoscale openings with graphene requires additional patterning due to its two-dimensional nature.…”

Domain matching epitaxy of GaN films on a novel langasite substrate: an in-plane epitaxial relationship analysis

“…The dislocation densities of GaN on the LGS substrate were found to be one or two orders of magnitude higher when compared to the sapphire substrate or the earlier reports. 26,32,33 Although the FWHM and dislocation density values of GaN grown on the LGS substrate are mediocre when compared to the GaN films grown on conventional substrates, it is expected that further optimization of growth conditions like growth temperature, thickness, buffer layer, and V-III ratio will undoubtedly address the difficulties of growing better quality GaN films on LGS, the study into which is currently underway. Fig.…”

Epitaxial growth and its mechanism of GaN films on nitrided LiGaO2(001) substrates by pulsed laser deposition

“…Meanwhile, the crystalline quality of GaN films grown on nitrided LiGaO 2 substrates achieved in this work is much better than that of the GaN films grown on sapphire by PLD, 22 and is comparable to state-of-the-art GaN films grown by MOCVD and PLD on other substrates. 41,42 The N-face GaN monolayer is formed by the high-temperature nitridation before the growth of GaN films by PLD, which is beneficial to the nucleation of GaN and shows a reduction in the formation of threading dislocations when compared with films grown on non-nitrided LiGaO 2 substrates. 14,43 GIXR is introduced to examine the structural properties of GaN/LiGaO 2 interfaces.…”