Preparation of MAPbI3 perovskite film by pulsed laser deposition for high-performance silicon-based heterojunction photodetector

This study investigates the preparation and characterization of CH3NH3PbI3 (MAPbI(3)) perovskite thin films. The films were prepared using a one-step pulsed laser deposition technique at different laser fluences. Structural, optical, and electrical properties of CH3NH3PbI3 films were investigated at various laser fluences. The X-ray diffraction (XRD) studies confirm the formation of beta-MAPbI(3) films. The optical energy gap of MAPbI(3) pemvskite film was calculated and is found to be in the range of 1.53-1.68 eV. Scanning electron microscope (SEM) analysis reveals the formation of rod-like and platelet morphologies, while energy dispersive X-ray spectroscopy analysis reveals that the [I]/[Pb] ratio of the films prepared with 2, 2.5, and 3 J/cm(2) was 1.3, 2.3, and 1.36, respectively. Hall effect results confirm that the MPPbI3 films are p-type and the mobility of MAPbI(3) film decreases from 0.26 to 0.084 cm(2)V(-l)s(-1) as laser fluence increases from 2 to 3 J/cm(2). The optoelectronic characteristics of the p-MAPbI(3)/n-Si photodetector were investigated as a function of laser fluence. By selecting an optimum laser fluence, a maximum responsivity of 2.57 A/W and an external quantum efficiency of 7.08 x 102% at 450 nm were obtained. The energy band lineup of the p-MAPbI(3)/n-Si photodetector fabricated with 2.5 J/cm(2) was constructed.