The Effect of ZnO Coating Amount on The Efficiency of n-ZnO/p-Si Heterojunction Solar Cell

In this study, the effect of zinc oxide (ZnO) coating amount on the efficieny of n-type zinc oxide/p-type silicon (n-ZnO/p-Si) heterojunction solar cell was investigated. ZnO nanoparticles were synthesized by sol gel method. The synthesized nanoparticles were coated on glass substrates and p-Si substrates using spin coating method. The coating process was carried out in different amounts as 2, 4, 5 and 15 times. After the coating process, the thin film coated substrates were placed in a square furnace and annealed at 500 oC for 30 min. Structure characterization and surface morphology were analyzed using X-ray diffraction (XRD) method and scanning electron microscopy (SEM). For each nZnO/p-Si heterojunction solar cell structure, short circuit current (Isc) and open circuit voltage (Voc) were determined by electrical measurements and efficiency (n) calculations were made. All processes were performed at room temperature. According to this study, the efficiency of solar cells increases with increasing the amount of ZnO coating up to a critical thickness and decreases when the critical thickness is exceeded (due to the more ZnO coating). From this it was concluded that the amount of ZnO coating (ZnO layer thickness) is an important parameter affecting the performance of solar cells