Determination of Optical Band Gap and Heat Dissipation of Ga1-xMnxAs with Light in UV-VIS-IR Region using OSA SPECTRO 320

Abstract

Heat generated by silicon-based transistors due to high energy photo irradiation interferes with the electronic conductivity of transistors in the ICs. There is need to search for an alternative semiconductor material for making diodes and transistors with little or no heat dissipation. Dilute magnetic semiconductor such as Gallium Arsenide (GaAs) has demonstrated to be a better candidate to substitute silicon in electronic technology. UV-VIS-IR light was illuminated on the Ga_1-xMn_xAs samples of thickness 500nm?1000nm of varied doping levels during the study. Reflectance and transmittance spectra were determined using OSA SPECTRO 320 with light obtained from sodium lamp (240V, 100 W) with irradiance of 33.4807 W/m². The maximum absorbance within the UV-VIS-IR range was, A? 83.82% at ??200nm and minimum absorbance was, A?0.96% at ??300nm with Ga_1-xMn_xAs, x=20% having the highest absorbance value and Ga_1-xMn_xAs, x=1%, the least absorbance. For Ga_1-xMn_xAs; x=0, x=10%, x=1% and x=20%; maximum absorbance occurred at UV region while for x=50%, maximum absorbance was observed at ??707nm. The results show that GaAs generate most heat due to its wide optical energy gap of 1.43eV while for x=1% dissipates little heat because of its small optical energy gap of 0.36eV.

Keywords: Optical absorbance, photo irradiation, Gallium Arsenide, Gallium manganese arsenide, doping, heat dissipation, ultraviolet light