Front surface field formation for majority carriers by functional p-NiO layer employed Si solar cell

• Published in: Applied physics letters Vol. 109; no. 13
• Main Authors: Patel, Dipal B., Kim, Hong-Sik, Patel, Malkeshkumar, Chauhan, Khushbu R., Park, Jeong Eun, Lim, Donggun, Kim, Joondong
• Format: Journal Article
• Language: English
• Published: Melville American Institute of Physics 26.09.2016
• Subjects: Applied physics; Current carriers; Electrical properties; Light; Majority carriers; Nickel oxides; Photovoltaic cells; Reflectance; Signal analysis; Silicon wafers; Solar cells
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4963259

An optically transparent and electrically conductive p-NiO layer was deposited on a conventional n-Si/p-Si solar cell, which improved the device performance. The transmittance and reflectance properties of the p-NiO layer were found to be much better than the SiNx layer in the visible light region. Impedance spectroscopic study under varying bias and illumination conditions was carried out to understand the underlying mechanisms governing the device performance. An AC signal analysis revealed that the p-NiO layer acted as a front surface field region for majority charge carriers. In addition, the p-NiO layer significantly improved Si solar cell performances due to the improved properties of parasitic resistances. The optically transparent NiO layered Si device (p-NiO/n-Si/p-Si) spontaneously enhanced the electrical properties, resulting in the substantially improved fill factor value of 74% from 34.3% of the bare n-Si/p-Si device. The existence of a front surface field increased the lifetime of carriers to 92 μs for the p-NiO/n-Si/p-Si solar cell compared to only 43 μs for an n-Si/p-Si cell. We may suggest a functional NiO layer to the efficient designs for Si solar cells.