Radiation-Hard, High Efficiency InP/InN Tandem Cells

Award Information
Agency: Department of Defense
Branch: Missile Defense Agency
Contract: HQ0006-04-C-7104
Agency Tracking Number: B045-017-0097
Amount: $99,931.00
Phase: Phase I
Program: STTR
Awards Year: 2004
Solitcitation Year: 2004
Solitcitation Topic Code: MDA04-T017
Solitcitation Number: N/A
Small Business Information
One Patriots Park, Bedford, MA, 01730
Duns: 065137978
Hubzone Owned: N
Woman Owned: N
Socially and Economically Disadvantaged: N
Principal Investigator
 Steven Wojtczuk
 Senior Scientist
 (603) 595-8900
Business Contact
 Mark Little
Title: CEO, Spire Biomedical, Inc.
Phone: (781) 275-6000
Email: mlittle@spirecorp.com
Research Institution
 Lawrence Berkeley Laboratory
 Joel Ager
 One Cyclotron Road
Berkeley, CA, 94720
 (510) 486-6715
 Nonprofit college or university
Spire proposes to investigate InP/InN tandem solar cells for applications where extreme radiation-hardness is needed. Indium phosphide (InP) has proven itself as a radiation-hard cell material, and indium nitride (InN) has shown superior radiation resistance to 2MeV protons. InP (1.34 eV) and InN (0.7eV) bandgaps allow current-matching (38 mA/cm2) under the AM0 spectrum, enabling two-terminal operation. We will investigate use of a pseudomorphic InGaP window to boost InP top cell efficiency from its current 19% one-sun AM0 level to 22%. We describe a process that allows the InP top cell to be undisturbed by dislocations from the InN growth. The 0.7eV InN bottom cell has an upper efficiency limit of ~9% AM0; however, the growth of InN would introduce substantial dislocations, and its efficiency would likely be about 4%. However, the dislocations should not compromise the InN radiation hardness, and we believe that the proposed research should lead to tandem space cells with efficiencies of ~26% (1 sun AM0, 25C) which would be flat in power output to fluences beyond 1e16 1MeV electrons/cm2.

* information listed above is at the time of submission.

Agency Micro-sites

US Flag An Official Website of the United States Government