Spatiotemporal Nonlocal Analysis of Hygro‐Photo‐Thermoelastic Cylindrical Semiconductors Within the MGT Framework Including Viscoelastic Damping

ABSTRACT This study develops a comprehensive mathematical framework for investigating the coupled hygro‐photo‐thermoelastic behavior of semiconductor cylinders within the Moore–Gibson–Thompson (MGT) theory of generalized thermoelasticity. The formulation addresses the nonphysical prediction of infinite thermal wave speed associated with classical Fourier conduction and simplified thermoelastic models. By adopting a hyperbolic heat‐conduction description, the model represents finite thermal propagation and offers a more physically consistent description of transient heat transport in microscale semiconductor structures. To capture scale‐dependent effects, a Klein–Gordon‐type operator containing spatial and temporal nonlocal parameters is incorporated into the governing constitutive equations. This addition describes microstructural interactions, delayed energy transfer, and nonlocal stress distributions that have become important in miniaturized devices. Although the present analysis is limited to linear elasticity and ideal cylindrical geometry, it provides useful insight into the coupled thermal, mechanical, hygroscopic, diffusive, and photothermal responses of semiconductor components used in precision sensing applications. The study also examines how hygroscopic swelling, spatiotemporal nonlocality, MGT relaxation times, and viscoelastic damping ratios influence the dynamic response. A hierarchical comparison of three progressively coupled models (the photo‐thermo‐hygro‐mechanical‐diffusion, photo‐thermo‐mechanical‐diffusion, and thermo‐mechanical‐diffusion frameworks) separates the roles of moisture, photoexcitation, mass diffusion, and thermal relaxation. Generally, the findings provide practical engineering guidance for reducing thermoelastic stresses and improving thermal management in humid environments. These results support improved design, performance prediction, and structural reliability of MEMS/NEMS devices, photothermal sensors, aerospace components, and advanced telecommunication technologies. They also assist in selecting material parameters and operating conditions for laser‐irradiated semiconductor systems exposed to moisture gradients.