Fabrication and characterization of nano‐porous GaN template for strain relaxed GaN growth

Hartono, H.; Soh, C. B.; Chua, Soo-Jin; Fitzgerald, Eugene A.

doi:10.1002/pssb.200674705

Cited by 14 publications

(12 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Moreover, porous GaN template could reduce the dislocation density and allow high-quality GaN overgrowth. 9 On top of that, porous GaN shows efficient luminescence in relative to the as-grown GaN, 8 which are useful properties in optoelectronics applications. Moreover, porous structures produce a high-surface area to volume ratio, suggesting its potential to be used in sensor applications.…”

Section: Introductionmentioning

confidence: 99%

Characteristics of porous GaN prepared by KOH photoelectrochemical etching

Radzali

Zainal

Yam

et al. 2014

Materials Research Innovations

View full text Add to dashboard Cite

This paper presents the structural and optical studies of porous GaN prepared by photoelectrochemical etching in diluted KOH under different etching durations. Such etching technique is a cheaper and simpler way of fabricating porous structure. The as-grown and porous GaN samples were investigated by field emission scanning electron microscopy, high resolution X-ray diffraction and Raman spectroscopy. Field emission scanning electron microscopy measurement allowed us to observe the morphology of the porous samples, and we found that the pore density increased with etching duration. From high resolution X-ray diffraction characterisation, the width at half maximum value of the rocking curve at (0002) and (10 12) plane decrease for all porous samples because of the reduction in dislocation density. Furthermore, as compared to the as-grown sample, the porous samples exhibit a significant enhancement of Raman peak intensity because of multiple scattering of light from the GaN crystallite sidewalls. Overall, this study shows that the surface nanostructure could improve the structural and optical properties of GaN. This is an initial demonstration to show the prospect of the porous GaN structure in optical and sensor applications.

show abstract

Section: Introductionmentioning

confidence: 99%

Characteristics of porous GaN prepared by KOH photoelectrochemical etching

Radzali

Zainal

Yam

et al. 2014

Materials Research Innovations

View full text Add to dashboard Cite

show abstract

“…This explained the mechanism behind dislocation annihilation in regrown GaN on nanoporous GaN template with the use of additional interfacial GaN buffer layer. enhanced electrochemical etching were reported elsewhere [12]. A GaN buffer layer of 100 nm was first grown on nanoporous GaN template at chamber temperatures of 750 °C, 850 °C and 1000 °C (labelled as sample A, B and C) followed by deposition of a 2 µm thick high temperature GaN epilayer [13].…”

Section: Methodsmentioning

confidence: 99%

“…Several techniques have been proposed for dislocation reduction for GaN grown on sapphire substrate which include insertion of cracked AlGaN, SiN and Si x Al 1-x N interlayers [8,9], selective lateral overgrowth of (ELO) GaN [10] and patterned sapphire substrate [11]. We have also reported on the generation of low defect density GaN with the use of nanoporous GaN template [12]. In this article, the effect of subsequent regrowth of GaN buffer layer on nanoporous GaN at different chamber temperature is studied and the mechanism behind threading dislocations reduction in GaN film subsequently overgrown is reported.…”

Section: Introductionmentioning

confidence: 99%

Threading dislocations annihilation in regrown GaN film on nanoporous GaN template

Soh

Hartono

Chow

et al. 2009

Phys. Status Solidi (c)

Self Cite

View full text Add to dashboard Cite

Regrowth of GaN buffer layer on nanoporous GaN at different chamber temperature of 750 °C, 850 °C and 1000 °C are used to study the mechanism behind threading dislocations reduction in the GaN film subsequently overgrown. The growth of a 100 nm GaN buffer layer at 850 °C causes dislocations to bend into the underlying GaN and annihilated at the interface of GaN buffer/nanoporous GaN. Thermal treatment of nanoporous GaN in MOCVD growth chamber at 850 °C in NH3 and N2 ambient leads to the pinning of the threading dislocations at its surface edge steps by impurity –vacancy complexes of SiNx. The SiNx are formed by the impinging adatoms of NH3 which interact with Si dangling bonds at the subgrain boundaries of the nanoporous Si‐doped GaN. When the nanoporous GaN sample undergoes rapid thermal annealing in N2 ambient, no effective filling of these voids are observed and dislocations density is not substantial reduced. Regrowth of GaN at 850 °C re‐structured the nanoporous GaN, forming a SiNx complex at the voids or pores which pinned dislocation propagation. This explained the mechanism behind dislocation annihilation in regrown GaN on nanoporous GaN template with the use of additional interfacial GaN buffer layer. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

show abstract

“…Therefore, porous GaN has a potential to be used as a template for subsequent nitrides growth. Moreover, porous GaN has a high surface to volume ratio and shows improvement in optical properties [5], which make it a suitable structure for advanced sensor and optical devices.…”

Section: Introductionmentioning

confidence: 99%