AlGaAs solar cells grown by MBE for high-efficiency tandem cells

✍ Scribed by Y. Yazawa; T. Kitatani; J. Minemura; K. Tamura; K. Mochizuki; T. Warabisako

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 276 KB
• Volume: 35
• Category: Article
• ISSN: 0927-0248
• DOI: 10.1016/0927-0248(94)90120-1

✦ Synopsis

A1GaAs solar cells for A1GaAs/GaAs tandem cell applications have been investigated. The performance of the AIGaAs cell grown by a molecular beam epitaxy (MBE) technique is believed to have strong dependence on growth temperature. The conversion efficiency, electrical properties, and the crystal quality of A1GaAs cells MBE grown at different temperatures have been characterized and correlations between each characteristic are discussed. The conversion efficiency is maximized at a growth temperature of 660°C. This agrees well with the results that the bulk recombination current is the lowest at this temperature. The structure of an AIGaAs cell in the AIGaAs/GaAs tandem configuration is optimized through numerical simulation using the parameters obtained from the A1GaAs and GaAs single junction cells. The efficiency for tandem cells is shown to be the highest when the thickness of the A1GaAs cell was chosen so that the incident light near the absorption edge might be shared with the bottom GaAs cell.