Self-Powered High-Performance WS2 Photodetector via a Monolithic p–i–n Homojunction

High Resolution Image Download MS PowerPoint Slide Lateral homojunction photodetectors (PDs) offer high responsivity and fast response, yet challenges in tailoring carrier concentrations in two-dimensional transition-metal dichalcogenides (TMDs) have limited their implementation. Here, we demonstrate a high-performance self-powered monolithic lateral p–i–n homojunction PD using multilayer WS 2 . To our knowledge, this study is the first report of achieving tunable, multilevel compensation doping via WO X formation using only time-controlled and region-selective ultraviolet (UV)/ozone oxidation. The oxidation process transforms WS 2 through distinct phases: initial WO X (2 < X < 3) formation with thickness growth (0–90 min), increased WO 3 ratio without thickness change (90–120 min), and self-limited saturation (>120 min). Photocurrent mapping confirms the formation of a lateral p–i–n hom…