Material Requirements for Buffer Layers Used to Obtain Solar Cells with High Open Circuit Voltages
- National Renewable Energy Laboratory
- Carl von Ossietzky Universitaet: Oldenburg, Germany
This paper discusses material requirements for junction layers needed to obtain solar cells with highest possible open-circuit voltages (VOC). In a typical a-Si:H-based ''p/i/n'' solar cell, this includes the transparent conductive oxide (TCO) contact layer, the p-layer, a ''buffer layer'' inserted at the p/i interface, and the surface portion of the intrinsic layer. In HIT-cells, the i-layer between (n-type) c-Si and (p-type) a-Si:H may be regarded as the buffer. Our suggestion to obtain high values of VOC relies on using materials with high lifetimes and low carrier mobilities that are capable of reducing surface or junction recombination by reducing the flow of carriers into this loss-pathway. We provide a general calculation that supports these approaches and can explain why these schemes are beneficial for all solar cells.
- Research Organization:
- National Renewable Energy Lab. (NREL), Golden, CO (United States)
- Sponsoring Organization:
- US Department of Energy (US)
- DOE Contract Number:
- AC36-99GO10337
- OSTI ID:
- 6939
- Report Number(s):
- NREL/CP-520-26363; ON: DE00006939; ON: DE00006939; TRN: US200310%%89
- Resource Relation:
- Journal Volume: 557; Conference: Presented at the Material Research Society's Spring Meeting, San Francisco, CA (US), 04/06/1999--04/10/1999; Other Information: Supercedes report DE00006939; PBD: 2 Apr 1999; PBD: 2 Apr 1999
- Country of Publication:
- United States
- Language:
- English
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