HEMT Inspired GaN Optical Waveguides: Analysis Under Thermal Stress and Prospects

Abstract

In this paper, high electron mobility transistor (HEMT) inspired aluminium gallium nitride (AlGaN)/gallium nitride (GaN)/aluminium nitride (AlN) optical waveguides are proposed under thermal stress using silicon (Si), silicon carbide (SiC), and sapphire (Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) substrates. The interaction of light with the thermal stress range of 20°C to 700°C is analyzed and an optimized framework design by adjusting the core, cladding, and substrate thicknesses is presented in this work. The study suggests that from the dispersion and confinement loss analysis, the SiC substrate-based GaN HEMT is suitable for high temperature and sensing platforms compared with silicon (Si) and sapphire substrates based HEMTs structure. The thermal stress-induced studies will mainly be utilized for sensing, nonlinear applications like tunable supercontinuum generation and spectroscopy in harsh environments. In addition, waveguide analysis based on HEMT inspired GaN optical waveguide proposed here in an optical domain potentially be used in electro-optical modulator application due to its ability to operate in both electrical and optical domain.