Interface engineering of 4H-SiC-based UV photodetectors: A comprehensive review

Ultraviolet (UV) photodetectors based on wide-bandgap semiconductors are essential for next-generation sensing technologies operating in harsh and energy-limited environments. Because of its wide bandgap (3.26 eV), high thermal conductivity, and radiation tolerance, 4H-silicon carbide (4H-SiC) provides an ideal material foundation for realizing self-powered and deep-UV detection. However, the performance of these devices is often constrained by intrinsic defects, interface states, and recombination losses that limit charge transport and long-term stability, underscoring the urgent need for interface-driven design strategies. This review provides a comprehensive, mechanism-based overview of recent progress in self-powered 4H-SiC UV photodetectors, emphasizing interface engineering through heterostructure design, dielectric integration, and incorporation of carbon-based and 2D materials enables enhanced carrier separation, spectral selectivity, and device reliability. This work uniquely establishes quantitative correlations between interface properties and device figures of merit, highlights emerging architecture such as avalanche and phototransistor configurations, and discusses their scalability and integration prospects for autonomous UV sensing systems. By bridging material science, device physics, and system-level functionality, this review defines a unified framework for achieving high-efficiency, self-powered, and environmentally resilient 4H-SiC photodetectors, guiding future research toward scalable and intelligent UV detection technologies.