Application of Cu2O based nanostructure as photodetector in broad spectral region

In this study, electro-optical measurements of the hydrothermally synthesized Cu2O thin film device were performed and were found to give very good photoresponse in the UV-vis-IR region. The obtained structure was analyzed by Scanning Electron Microscope (SEM) and X-ray Diffraction (XRD). When the XRD analysis of the Cu2O thin film is examined, these structural characterization results are supported by electrical measurements and SEM results. The SEM image of the prepared Cu2O thin film shows a granular structure. The crystal size values were found to be between 59.23 and 81.37 nm using different calculation methods. Device parameters were determined by current-voltage (I-V) measurements taken in the dark and in the light. Photodetector parameters were determined using visible light sources with powers ranging from 10 mW/cm(2) to 150 mW/cm(2) and UV and IR light sources with powers of 8 mW/cm(2). The fabricated heterojunction exhibits maximum responsivity R = 4.85 mA/W in visible light (10 mW, V=-2.0 V), D*=9.47 x 10(9) (10 mW, V=-2.0 V) Jones and on/off ratio = 1.08 x 10(3) (150 mW, V = 0.0 V). Furthermore, R = 8.4 mA/W (365 nm), R = 7.5 mA/W (395 nm), R = 9.1 mA/W (590 nm), R = 8.9 mA/W (850 nm) were obtained, while D* values of 2.2 x 10(10) Jones (365 nm), 1.9 x 10(10) Jones (395 nm), 2.6 x 10(10) Jones (590 nm) and 2.2 x 10(10) Jones (850 nm) were determined. Furthermore, EQE values determined for 590 nm, 850 nm, 365 nm and 395 nm, were 28.6%, 23.4%, 19.1%, and 13.0%, respectively.