NASA SBIR 2005 Solicitation


SUBTOPIC TITLE:Deep Space Power Systems
PROPOSAL TITLE:High Operating Temperature, Radiation-Hard MIM Thermophotovoltaic Converters

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Spire Corporation
One Patriots Park
Bedford, MA 01730-2396
(781) 275-6000

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Steven J Wojtczuk
25 Sagamore Park Road
Hudson, NH  01730-2396
(603) 689-1204

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
Spire Corporation is developing a key component for thermophotovoltaic (TPV) power technology for deep space missions. We are developing InGaAs monolithically interconnected modules (MIMs) that convert thermal photons from the ~1100C General Purpose Heat Source (GPHS) into electrical power. The innovation is that these MIMs are designed to operate at higher cell temperatures (150C) and be more radiation-hard than current MIMs to better match the cell environment on missions. In Phase 1, we developed a model that predicts an optimum InGaAs bandgap (adjustable during epigrowth) for the operating temperature and 1100C blackbody GPHS spectrum of ~0.7eV, made sample devices, and tested temperature coefficients to confirm the model and measured data agree (e.g. model predicts ?1.7mV/C for Voc vs. ?1.8mV/C for data). In Phase 2, we will perform five iterations of a model, design, epitaxially grow, process, and test cycle. Data from each cycle will be used to improve the next design. Testing will include both radiation, temperature stability and accelerated life testing. Before program completion, we will survey NASA and commercial space power contractors for needs and make samples of the best design to distribute among space power contractors as a step toward generating interest and commercial sales.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
Deep space missions to the outer planets may use radioisotope heat sources to supply power to the probe. Thermoelectrics have been used in the past, and thermophotovoltaic technology has been proposed as a higher (~3X) efficiency replacement for these thermoelectric converters.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
Uses for a radiation-hard high-operating-temperature cell technology are somewhat limited, but "quiet" power on nuclear-powered naval vessels are another area where this technology may see application.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Nuclear Conversion
Optical & Photonic Materials
Photovoltaic Conversion
Power Management and Distribution
Radiation-Hard/Resistant Electronics
Semi-Conductors/Solid State Device Materials
Thermoelectric Conversion

Form Printed on 07-25-06 17:04