This paper presents the fabrication and performance analysis of Zinc Oxide (ZnO) and Ag doped ZnO (SZO) based Metal-Semiconductor-Metal (MSM) ultraviolet (UV) photodetectors. The films were constructed on p-type silicon (Si) (100) substrates by sol-gel technique. Silver (Ag) electrodes were used as a Schottky contact for the fabricated devices. The structural, optical, and electrical properties for the fabricated films were studied and analyzed to show the effects of Ag dopants. With the applied voltage in the range of (-5 to 5 V) under dark condition, the values of the Schottky contact parameters were extracted and compared. Under UV illumination (254 nm) with different optical power levels, the performance parameters were extracted. The SEM image showed a non-uniform distribution of the Ag dopants, these dopants were formed clusters and this clusters acts as traps for the incident light. The saturation current was decreased for the device based on Ag doped ZnO film which enhanced the performance of the device.

This paper presents the fabrication, characterization and performance analysis of Zinc Oxide (ZnO) and Sliver doped Zinc Oxide (SZO) based interdigitated Metal-Semiconductor-Metal (MSM) Schottky barrier UV photodetectors. The ZnO and SZO thin films were grown on p-type silicon (Si) (100) substrates by sol-gel and spin coating technique. The three devices were fabricated using silver (Ag) as Schottky contact photodetectors based on un-doped ZnO, SZO with (2% and 4%) doping ratios. The structural and morphological properties of ZnO and SZO thin films were studied using Scanning Electron Microscopy (SEM), X-ray diffraction (XRD), and Atomic Force Microscopy (AFM). The optical and electrical properties for these films were studied using UV-visible and Hall effect measurements. With the applied voltage in the range of (-5 to 5 V) under dark condition, the values of the saturation current, barrier height, ideality factor, reach through and flat band voltages were extracted. Under UV illumination with different optical power levels ranging from (163.2µw-171.8µw) with a wavelength (254 nm), the values of the photo current, contrast ratio, responsivity, quantum efficiency, detectivity, and noise equivalent power were extracted. The SEM images showed a non-uniform distribution of the Ag dopants, these dopants were formed clusters and this clusters increased as the amount of Ag dopants increased. The mobility, carrier concentration, and roughness for the SZO films were increased as compared with undoped film. The optical band gap and the transmittance were decreased with increasing in the doping ratio. It was found that the saturation current decreased by a factor of 4, and 12 for the devices based on Ag doped ZnO (with 2% and 4 %) doping ratio. The sensitivity was significantly increased with increasing in doping ratio. This enhancement attributed to the roughness of the Ag doped ZnO thin films. Thus, this study revealed that the Ag doped ZnO films resulted in devices exhibiting better photoresponse as compared to those using un-doped ZnO thin films.