Hydrogen etch of GaN and its application to produce porous GaN caves

Yeh, Yen Hsien; Hsu, Yung-Chang; Wu, Yung-Hsien; Chen, Kuei Ming; Lee, Wei-I

doi:10.1117/12.874422

Cited by 3 publications

(2 citation statements)

References 14 publications

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“…The detailed metal-assisted chemical etching mechanism of GaN is not known; however, it is well accepted that the Nface of GaN is unstable compared with the Ga-face [6,26], and it can be etched under UV illumination, releasing N 2 [18,20]. Further, under comparable conditions, the metalassisted chemical etching rate of GaN is much smaller than Si.…”

Section: Mechanismmentioning

confidence: 99%

Catalyst and processing effects on metal-assisted chemical etching for the production of highly porous GaN

Geng

Duan

Grismer

et al. 2013

Semicond. Sci. Technol.

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Metal-assisted chemical etching is a facile method to produce micro-/nanostructures in the near-surface region of gallium nitride (GaN) and other semiconductors. Detailed studies of the production of porous GaN (PGaN) using different metal catalysts and GaN doping conditions have been performed in order to understand the mechanism by which metal-assisted chemical etching is accomplished in GaN. Patterned catalysts show increasing metal-assisted chemical etching activity to n-GaN in the order Ag < Au < Ir < Pt. In addition, the catalytic behavior of continuous films is compared to discontinuous island films. Continuous metal films strongly shield the surface, hindering metal-assisted chemical etching, an effect which can be overcome by using discontinuous films or increasing the irradiance of the light source. With increasing etch time or irradiance, PGaN morphologies change from uniform porous structures to ridge and valley structures. The doping type plays an important role, with metal-assisted chemical etching activity increasing in the order p-GaN < intrinsic GaN < n-GaN. Both the catalyst identity and the doping type effects are explained by the work functions and the related band offsets that affect the metal-assisted chemical etching process through a combination of different barriers to hole injection and the formation of hole accumulation/depletion layers at the metal-semiconductor interface.

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Section: Mechanismmentioning

confidence: 99%

Catalyst and processing effects on metal-assisted chemical etching for the production of highly porous GaN

Geng

Duan

Grismer

et al. 2013

Semicond. Sci. Technol.

View full text Add to dashboard Cite

show abstract

“…Dry etching methods are widely used and include reactive ion etching 23,24 and hydrogen etching. 25 However, dry etching treatment may cause a few unintended damages to samples. Electroless wet etching is also a promising approach, but it often requires processing and post-processing of the samples using toxic substances at high concentrations, such as hydrofluoric and nitric acids.…”

Section: Introductionmentioning

confidence: 99%