© 2020 Elsevier B.V.Fabrication and characterization of metal/semiconductor/polymer/metal (MSP) heterojunction diode are reported. The Al/p-Si/P3HT/Ag MSP heterojunction have been manufactured by a homemade ultrasonic spray pyrolysis (USP) method, and the organic layer has a thickness of ∽150 nm and silver as front contact is deposited by physical vapor deposition (PVD) technique. The organic layer is deposited on glass and has been subject of XRD diffraction, patterns which revealed a grain size of ∽18 nm, UV–Vis measurement and scanning electron microscope (SEM) images characterization. Furthermore, electrical parameters obtained from I–V current voltage and C–V capacitance voltage at room temperature and under dark conditions of the fabricated MSP heterojunction is investigated. The average series resistance Rs calculated from several methods is found to be 7.30 KΩ and are in close agreement for several calculation methods, also for ɸB the barrier height, n ideality factor with values of ∽0.72 eV and 4.07, respectively. The peak of C–V occurs at a low frequency due to presence of interface inside organic MSP device.