Annealing Effects on IWO/Si Heterojunction Photodetector

This study presents the fabrication and systematic investigation of indium tungsten oxide (IWO)/silicon heterojunction photodetectors (PDs), with emphasis on the influence of annealing temperature on their photoelectric performance. Experimental results indicate that the annealing temperature critically modulates the crystalline structure, defect density, and surface morphology of the IWO layers, thereby affecting the device's photoresponse characteristics. It is observed that an annealing temperature of 350 °C for the IWO/Si heterojunction PD is optimal, yielding a responsivity of 3.32 A W −1 and a specific detectivity of 5.8 × 10 11 cm Hz 1 / 2 /W. Furthermore, the device demonstrates rapid response dynamics under 450 nm illumination, characterized by a response time of ≈1 ms and a high photoswitching ratio of 1.8 × 10 3 . These figures of merit indicate the device's potential for applications requiring the detection of high‐sensitivity optical signals.