Experimental and simulation analyses of bulk GaN-based metal-semiconductor-metal ultraviolet photodetectors

This study presents a comprehensive experimental and simulation analysis of bulk c-plane gallium nitride (GaN)based metal-semiconductor-metal (MSM) ultraviolet (UV) photodetectors (PDs). The PDs were fabricated using a straightforward approach, with silver paste serving as the electrode material. The fabricated devices demonstrated excellent performance, achieving high responsivity (12.8 A/W), sensitivity (1864 %), photo-to-dark current gain (19.64), detectivity (1.11 x 1011 J), low noise equivalent power (1.64 x 10-12 W/cm2Hz1/2), and fast response times (rise time: 0.1 s, decay time: 0.125 s) under 6 V bias at 365 nm illumination. To further understand the underlying physical mechanisms, a Silvaco TCAD ATLAS simulator was employed, revealing a trend consistent between the simulation results and experimental data. This agreement underscores the reliability and effectiveness of the fabricated GaN-based MSM UV PDs, highlighting their potential for highperformance UV detection applications.