Photonic Crystals Induced Enhancement of Light‐Matter Interactions and Dark Current Suppression for High‐Performance Ga₂O₃ Solar‐Blind Photodetectors

Abstract Ga 2 O 3 with a wide bandgap has emerged as a natural material system for solar‐blind photodetectors (SBPDs). However, its inherent weak light absorption and high dark current limit its practical application. Photonic crystals hold significant potential for advancing high‐performance optoelectronic devices due to their exceptional ability to harvest light. In this work, a novel photonic crystal nanohole is introduced to enhance light‐matter interactions in Ga 2 O 3 SBPDs. Through comprehensive design, fabrication, and characterization of the nanohole arrays, their effect on light‐matter interactions are demonstrated. The integration of nanohole arrays improves light harvesting by reducing reflectance and transmittance while increasing the local electric field, and it simultaneously reduces the dark current in Ga 2 O 3 photodetectors, resulting in a remarkable photoresponse. The impact of nanohole arrays' geometric features on the device performance is elucidated by precisely engineering its nanohole period, diameter, and depth. The highest responsivity observed across all devices is a record‐high 12474.01 A W −1 . This work provides a comprehensive analysis of the Ga 2 O 3 nanohole arrays, detailing structure design, underlying physical mechanisms, and device performance. It opens new opportunities to develop advanced Ga 2 O 3 ‐based SBPDs with photonic crystals.