Au-nanoparticles doped SiO 2 interfacial layer to promote the photovoltaic characteristics of Au/p-Si/Al solar cells Ahmed M. Nawar a, b, * , M.M. Makhlouf c, d, ** a Thin Films Laboratory, Physics Department, Faculty of Science, Suez Canal University, 41522, Ismailia, Egypt b Physics Department, Faculty of Science and Arts, 65931, AlMikhwah, AlBahah University, AlBahah, Saudi Arabia c Department of Physics, Turabah University College, Taif University, Turabah, 21995, Saudi Arabia d Department of Physics, Damietta Cancer Institute, Damietta, Egypt article info Article history: Received 11 June 2018 Received in revised form 4 September 2018 Accepted 11 September 2018 Available online xxx Keywords: MIS solar cell Au(NPs)/SiO 2 layer Impedance spectroscopy Negative capacitance Electrical mechanisms Photovoltaics abstract The Au/Au(NPs) doped SiO 2 /p-Si/Al heterojunction solar cell was achieved. The interfacial insulator layer of SiO 2 was, successfully, grown on p-Si (111) wafer using the thermal evaporating technique. The Au- nanoparticles (NPs in the range of 20e85 nm) were well dispersed on the amorphous matrix structure of SiO 2 film using flash evaporation method. The structural morphology of the film was investigated using field emission scanning electron microscopy. Some aspects of impedance spectroscopy of the solar cells were studied and in light of which; Nyquist spectra for the complex impedance of the cells were recorded at various frequency (100 KHz 3 MHz). The radii of the semi-circles of the Nyquist plot decreased with increasing the frequency. The capacitance-voltage (CeV) and conductance-voltage (G-V) characteristics were measured. The heterojunction cell showed the negative-capacitance behavior at certain frequencies. Moreover, the current-voltage (IeV) characteristics in dark and under illumination were also studied from which, the electronic transport mechanisms through the solar cell were evalu- ated. Some important parameters of the junction, such as the ideality factor, barrier height carrier, series and shunt resistances were extracted from the IeV curves. The photovoltaic behavior of the Au(NPs) doped SiO 2 /p-Si solar cell was evaluated and showed good performance. The photovoltaic parameters of the fabricated solar cell such as: open circuit voltage, short circuit current, fill factor and conversion efficiency were calculated as 0.46 V, 5.4 mA, 0.68 and 5.28%, respectively. © 2018 Elsevier B.V. All rights reserved. 1. Introduction In the recent decades, solar cells based on silicon (Si) had a share of over than 90% of the manufactured solar cells around worldwide [1]. The continuous research in the field of Si solar cell has intro- duced new insights, novel design and easy processing methods to reduce the cost of fabrication and enhance the conversion effi- ciency of the Si solar cells [2,3]. Schottky junction diode or solar cell in the simplest design consists of metal and semiconductor (MS). The electrical and photovoltaic characterizations of MS Schottky junction, strongly, depending on the type of fabrication method. In particular, the surface growth and the interfacial layers formation are the most considered conditions in the device setup process. These conditions affecting the electrical properties and photovoltaic parameters of the junction, such as barrier height, interface states, series resis- tance, shunt resistance, ideality factor and conversion efficiency that reflect the device performance. The insulator layer like SiO 2 , SnO 2 , Si 3 N 4 or polymer in between a metal and semiconductor (MIS) creates a potential barrier, which suppresses the majority carriers, and increases photogeneration current of the device compared to the MS Schottky diode and cell. Silicon dioxide (SiO 2 ) is one of the most important and famous insulator materials uti- lized in several applications of photovoltaic devices due to its interesting chemical and physical characterizations including low refractive index, high thermal stability, high corrosion resistance, low thermal conductivity and low price [4]. Additionally, SiO 2 has a unique mechanical characterization that enhances the adhesion of a material on the substrate [5]. * Corresponding author. Thin Films Laboratory, Physics Department, Faculty of Science, Suez Canal University, 41522, Ismailia, Egypt. ** Corresponding author. Department of Physics, Turabah University College, Taif University, Turabah, 21995, Saudi Arabia. E-mail addresses: nawarphysics@yahoo.com (A.M. Nawar), m_makhlof@ hotmail.com (M.M. Makhlouf). Contents lists available at ScienceDirect Journal of Alloys and Compounds journal homepage: http://www.elsevier.com/locate/jalcom https://doi.org/10.1016/j.jallcom.2018.09.104 0925-8388/© 2018 Elsevier B.V. All rights reserved. Journal of Alloys and Compounds xxx (2018) 1e11 Please cite this article in press as: A.M. Nawar, M.M. Makhlouf, Au-nanoparticles doped SiO 2 interfacial layer to promote the photovoltaic characteristics of Au/p-Si/Al solarcells, Journal of Alloys and Compounds (2018), https://doi.org/10.1016/j.jallcom.2018.09.104