Light-Weight, Low Cost, High-Efficiency Solar Cells Space Planar Arrays.
Abstract
The objective of this program was to produce an AlGaAs (or GaIriAsP) and Si mechanically stacked tandem solar cell that meets the program goals of PRDA 91-01 -PKRN POC. The band gap of the AlGaAs or GaInAsP top cell is 1.7 eV to current-match the Si bottom cell. These cells are joined by a process called eutectic metal bonding that places the two photovoltaic cells in series. Efficiencies of the Si bottom cells exceeded 16.5 percent under AMO illumination. However, these cells showed an unexpectedly large amount of radiation damage when the AMO spectrum was filtered to include only wavelengths longer than 0.73 pn, duplicating the environment of a Si cell in the tandem stack. Attempts to solve this problem with higher resistivity Si wafers and variation of junction depths were only partially successful. The radiation-degradation problem remains for the Si cell. The GaInAsP cells produced AMO efficiencies greater than 20 percent and showed low-temperature annealing of radiation- induced damage. This cell has significant potential for space applications.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1996
- Accession Number
- ADB209013
Entities
People
- Michael L. Timmons
Organizations
- RTI International