Performance Analysis of Graphene Oxide Based Photodetector for Broad Spectrum Light Sensing

Two-dimensional (2D) materials exhibit remarkable electrical and optical properties, making them promising candidates for optoelectronic devices. In this study, a graphene oxide (GO)-based photodetector was fabricated and evaluated over the wavelength range of 400–1000 nm. The GO film was characterized by SEM, cross-sectional SEM, and XRD, confirming uniform coverage and a typical layered structure. Key performance parameters, including photocurrent (Iph), photosensitivity (K), responsivity (R), and specific detectivity (D*), were systematically analyzed. The device exhibited a strong and stable photoresponse over a broad spectral range extending from the ultraviolet to the near-infrared region, with maximum performance at 1000 nm, where R = 2.107 A/W, D* = 2.55×1010 Jones, and NEP = 3.47×10-12 WHz-1/2. Current–voltage measurements confirmed enhanced photocurrent under illumination and nearly symmetric I–V curves, indicating bidirectional operation. Beyond 1000 nm, a decline in performance was observed, suggesting reduced efficiency in the mid-infrared region. These results highlight the GO/n-Si photodetector’s excellent broadband sensitivity and optimal performance near 1000 nm.