SAIP2025

Spectroscopic studies on In$_x$Ga$_{1−x}$N and In$_x$Ga$_{1−x}$N:Si

9 Jul 2025, 15:20

20m

Solomon Mahlangu House (University of the Witwatersrand, Johannesburg)

Oral Presentation Track A - Physics of Condensed Matter and Materials Physics of Condensed Matter and Materials

Speaker

Ongeziwe Mpatani (University of the Witwatersrand)

Description

{In$_x$Ga$_{1-x}$N} is a semiconductor widely used in optoelectronics$^1$. Significant advancements are being made to semiconducting materials to enhance their properties. One noteworthy approach is doping InGaN with silicon Si. Photoluminescence studies were conducted on samples with 10% In concentration, both with and without silicon (Si) doping. Earlier literature indicates that introducing Si reduces the full width at half maximum (FWHM) of the band-edge emission peaks$^2$. The spectra measured for the InGaN:Si samples display sharper peaks than those of pure InGaN, highlighting the potential of InGaN:Si as an ideal candidate for active layers in LEDs and laser diodes, thanks to its high emission efficiency. Additionally, measurements were performed from 10 K to room temperature to investigate the peak position shift as temperature changes. Our findings revealed an S-shape behaviour, indicating the presence of alloy disorder in both materials. Furthermore, the spectra show peaks of deep-level emissions, which were not found in earlier literature on InGaN$^3$. An explanation for these emission peaks and their temperature dependence will be discussed.

Refereneces
1. S. Nakamura, Rev. Mod. Phys., 87(4), 2015.
2. S. Nakamura et al., Jpn. J. App. Phys., 32, 1993.
3. S. Nakamura et al, Jpn. J. App. Phys., 31, 1992