Abstarct: In this research, in order to obtain a CdTe thin laxyer with optimal conditions without secondary phases, three methods, including chemical bath deposition, spray pyrolysis, and sputtering on glass substrates, were used. In addition, the properties of the photodiode and the variations of the CdTe laxyer thickness (by sputtering) on the photoresponse of the fabricated photodiode with Ag/CdTe/p-Si/Al heterostructure were investigated. In this research, the prepared samples were characterized by various methods, including field emission scanning electron microscope (FESEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), UV-Vis. spectroscopy, photoluminescence spectroscopy (PL), current-voltage (I-V) and current-time (I-t) measurements in dark and light illumination conditions. In the chemical bath method, various parameters, including annealing time, solution concentration, deposition time, and deposition temperature, were investigated. It was found that, compared to other samples, the one synthesized at 90 °C in 30 minutes from a structural and optical point of view has optimal behavior. In the spray pyrolysis method, we also synthesized laxyers in the presence of nitrogen gas under different conditions, including solution concentration and annealing, substrate temperature, and flow rate. The results in this section showed that, in general, the samples had better structural quality after annealing. Also, the sample with equal concentrations of pre-materials and substrate temperature, of 350 °C has shown better physical and electrical properties than other samples. In the sputtering method, we studied parameters such as deposition time and substrate temperature. The results showed that increasing the time duration of coating has an important role in the conductivity of the laxyers and reducing their electrical resistance, but the temperature of the substrate does not have a major effect on the physical properties of the laxyers. Finally, we investigated the effect of CdTe middle laxyer thickness (0, 80, and 120 nm) in Ag/CdTe/p-Si/Al heterostructure photodiodes on the photoresponse of the samples to halogen lamp light. It is found that all the studied samples have a rectifying characteristic, and the insertion of the interface laxyer has increased, by about one order of magnitude, the series resistance of the samples. It was also revealed that the sample with the thickest CdTe interface laxyer, as a result of a bigger photocurrent (IP) and a smaller dark current (ID), has the highest photoresponse ratio of ~ 300, which is the highest value reported in CdTe/p-Si heterostructure photodiodes.