Structural and Optical Studies of Undoped Porous GaN Prepared by Pt-Assisted Electroless Etching

Abstract:

Porous GaN structures were formed from crystalline GaN on conducting AL₂O₃ substrate using Pt-assisted electroless etching in HF: CH₃OH: H₂O₂ = 1:4:4 under illumination of 500 W UV lamp. Scanning electron microscope (SEM) photoluminescence (PL) and Raman spectra measurements evidenced important features of the pore morphology, nanostructures and optical properties. According to the SEM micrographs, the three-dimensional ridge structure appears with the formation of porous material between the ridges. The porous layer exhibited a substantial PL intensity enhancement with red-shifted band-edge PL peaks associated with the relaxation of compressive stress. The shift of E₂(high) to the lower frequency in Raman spectra of the porous GaN films further confirms such a stress relaxation.

• Periodical: Materials Science Forum (Volume 846)
• Pages: 358-365
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.846.358
• Online since: March 2016
• Authors: Ainorkhilah Mahmood*, Zainuriah Hassan, Naser Mahmoud Ahmed, Fong Kwong Yam, Lee Siang Chuah, Marina Mokhtar, Nurul Huda Mohd Noor, Siti Azlina Rosli
• Keywords: Photoluminescence (PL), Porous GaN, Pt-Assisted Electroless Etching, Raman Spectroscopy

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