Low Temperature AC Photoelectrochemical Etching of Si-doped n-type GaN: Nanostructure Fabrication for Enhanced MSM Photodetector Performance

Authors

Nur Iwani Nor Izaham, Faculty of Applied Sciences, Universiti Teknologi MARA, Shah Alam, Selangor, MalaysiaFollow
Ainorkhilah Mahmood, Department of Applied Sciences, Universiti Teknologi MARA Cawangan Pulau Pinang, Permatang Pauh, MalaysiaFollow
Rosfariza Radzali, Electrical Engineering Studies, College of Engineering, Universiti Teknologi MARA Cawangan Pulau Pinang, Permatang Pauh, MalaysiaFollow
Alhan Farhanah Abd Rahim, Electrical Engineering Studies, College of Engineering, Universiti Teknologi MARA Cawangan Pulau Pinang, Permatang Pauh, MalaysiaFollow
Nur Maizatul Azra Mothtar, Faculty of Health Sciences, Universiti Teknologi MARA Cawangan Pulau Pinang, Kepala Batas, MalaysiaFollow
Mahayatun Dayana Johan Ooi, School of Physics, Universiti Sains Malaysia, Minden, MalaysiaFollow
Naser Mahmoud Ahmed, Laser and Optoelectronics Engineering Department, Dijlah University College, Baghdad, IraqFollow

Abstract

This study has investigated the fabrication of porous Si-doped gallium nitride (GaN) using low-temperature alternating current photoelectrochemical (ACPEC) etching at varying etching durations for MSM photodetector applications. The structural and optical characteristics of the porous GaN samples were examined using a 400 W high-pressure mercury-vapour lamp (Hg-HPVL) and 4% KOH electrolyte with 50 Hz of 100 mA alternating current (AC). Current-voltage (I-V) measurements were conducted to analyse the platinum-deposited GaN for MSM photodetector performance. FESEM micrographs of the etched samples revealed coral-like and nano-tunnel pore formations, while AFM topography showed a significant increase in surface roughness compared to in the as-grown samples. The minimal difference between the average pore depth and RMS surface roughness values indicated successful fabrication of a nano-coral structure with a uniform, evenly distributed depth. Raman spectroscopy of the etched samples showed shifts in the A₁ (LO) peak wavelengths and an increase in the E₂ (high) peak intensity across different etching times compared to in the as-grown samples. XRD analysis further confirmed the presence of dislocation density along the x- and z-axis across all samples. Additionally, I-V measurements of the MSM photodetector demonstrated a higher current in all porous samples compared to in as-grown samples under various environmental conditions. These findings indicated that low-temperature ACPEC etching could be an effective approach for fabricating porous GaN with higher currents for photodetector applications.

Keywords

Low temperature, MSM photodetector, Nanostructure, Photoelectrochemical, Si-doped GaN

Article Type

Special Issue Article

First Page

151

Last Page

164

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.

How to Cite this Article

Izaham, Nur Iwani Nor; Mahmood, Ainorkhilah; Radzali, Rosfariza; Rahim, Alhan Farhanah Abd; Mothtar, Nur Maizatul Azra; Ooi, Mahayatun Dayana Johan; and Ahmed, Naser Mahmoud (2026) "Low Temperature AC Photoelectrochemical Etching of Si-doped n-type GaN: Nanostructure Fabrication for Enhanced MSM Photodetector Performance," Baghdad Science Journal: Vol. 23: Iss. 1, Article 12.
DOI: https://doi.org/10.21123/2411-7986.5138