Application of the chemical vapor-etching in polycrystalline silicon solar cells |
| |
Authors: | M Ben Rabha H Ezzaouia R Bennaceur |
| |
Institution: | Institut National de Recherche Scientifique et Technique, Laboratoire de Photovoltaïque et des Semiconducteurs, BP 95, 2050 Hammam-Lif, Tunisia |
| |
Abstract: | This paper reports a study of the application of chemical vapor-etching (CVE) for the rear surface and in the emitter of polycrystalline silicon (pc-Si) solar cells. The CVE technique consists of exposing pc-Si wafers to a mixture of HF/HNO3. This technique is used to groove the rear surface of the pc-Si wafers for acid vapors rich in HNO3 (HNO3/HF > 1/4), in order to realize rear-buried metallic contacts (RBMC) and the formation of a porous silicon (PS) layer on the frontal surface of the cell for volume ratio of HNO3/HF = 1/7. A significant increase of the spectral response in the long wavelength range was observed when a RBMC is formed. This increase was attributed to the reduction of the effective thickness of the base of the cells and grain boundary Al gettering. The achievement of a PS layer on the emitter of the pc-Si cells passivates the surface and reduces the reflectivity. The dark I-V characteristics of pc-Si cells with emitter-based PS show an important reduction of the reverse current together with an improvement of the rectifying behaviour. The I-V characteristic under AM1.5 illumination shows an enhancement of both short circuit current density and fill factor. The internal quantum efficiency is improved, particularly in the short wavelengths region. |
| |
Keywords: | 80 05 Rm 68 37 Hk 78 30 Hv 78 40 Fy |
本文献已被 ScienceDirect 等数据库收录! |