Study of photoelectric characteristics of p-PAn/n-Si junction

Abstract A p-type polyaniline (PAn) film was photoelectrochemically polymerized directly on a n/n + epitaxial silicon (Si) wafer in electrolyte and a p-PAn/n-Si junction was fabricated. The photocurrent and photovoltage can be clearly seen in the I p -V curve of junction. It i s demonstrated experimentally that the photocurrent spectrum of p-PAn/n-Si junction and the transmission spectrum of p-PAn film occur in same range of photon energy 1.8 – 2.8 eV, and it means that the PAn film in the junction offers a window for photons of 1.8 – 2.8 eV. The energy band structure and the photoelectric transformation process of the p-PAn/n-Si junction have been analyzed, and some factors affecting the photoelectric characteristics of p-PAn/n-Si junctions have been discussed in this paper.