Toward a better physical understanding of a-Si:H/c-Si heterojunction solar cells
- LPICM, CNRS, Ecole Polytechnique, 91128 Palaiseau (France)
Despite energy conversion efficiencies exceeding 22%, current understanding of the physics behind heterojunction solar cells remains incomplete. The role of hydrogen and ion bombardment during the plasma deposition as well as the influence of an epitaxial layer remains a subject of debate. Our results suggest that hydrogen plays a key role in the fabrication of high efficiency heterojunction solar cells. We show that ion bombardment is not as detrimental as is often thought. Moreover we find that an epitaxial layer is not necessarily harmful to the cell's V{sub oc}. We propose a criterion linking the layer's epitaxy and the cells' performance. To further investigate the role of the H{sub 2} plasma, we carry out in situ ellipsometry measurements on various kinds of c-Si wafers. The effects of this H{sub 2} plasma strongly depend on the resistivity of the c-Si wafer, suggesting that plasma conditions must be tuned to optimize cell efficiency according to the c-Si resistivity.
- OSTI ID:
- 21190092
- Journal Information:
- Journal of Applied Physics, Vol. 105, Issue 6; Other Information: DOI: 10.1063/1.3091283; (c) 2009 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0021-8979
- Country of Publication:
- United States
- Language:
- English
Similar Records
Progress in Silicon Heterojunction Devices by Hot-Wire CVD: Preprint
High Open-Circuit Voltage in Silicon Heterojunction Solar Cells