NASA SBIR 2003 Solicitation


PROPOSAL NUMBER:03-S2.01-8708 (For NASA Use Only - Chron: 034297)
SUBTOPIC TITLE:Sensors and Detectors for Astrophysics
PROPOSAL TITLE:Novel IR Detectors with Response up to 300 microns

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
236 St Martins Drive
Mableton ,GA 30126 - 1965
(404) 651 - 2709

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
Dr. Steven G. Matsik
236 St Martins Drive
Mableton ,GA  30126 -1965
(404) 463 - 9622
U.S. Citizen or Legal Resident: Yes

The proposed innovation is the development of a novel Heterojunction Interfacial Workfunction Internal Photoemission (HEIWIP) detector responding up to a cutoff wavelength ~300 microns using the well developed GaAs/AlGaAs system. The detection is by free carrier absorption in doped emitter layers followed by internal photoemission of the carrier over the interfacial workfunction and collection of the photoemitted carriers. The workfunction, and hence cutoff, can be adjusted by varying the composition of the emitter and barrier layers. The key properties of the proposed detectors are broadband response and the ability to tailor cutoff and a NEP of 10^{-20} W Hz^{-1/2}. In Phase II, the HEIWIP detector will be combined with an LED to form an up-conversion device whose output can be read with a conventional NIR CCD. The HEIWIP-LED detector system would have the ability to cover the range from 40-300 microns or longer in an array format without the use of a multiplexer with spatial resolution determined by the NIR CCDs. Because the HEIWIP would not be divided into pixels, the HEIWIP-LED would not have the difraction problems affecting focal plane arrays responding to 300 microns.

The ability to use a single power source for the detector and LED will reduce the mass and power requirements, fulfilling low cost, mass, and power requirements for NASA missions. The Filled Aperture InfraRed instrument will require detectors in this range. For planetary missions the HEIWIP could provide useful new capabilities for studying solar system objects. HEIWIPs could enhance the current remote sensing capabilities for mineral components, and the composition and structure of atmospheres. HEIWIPs will be useful in studying composition of gas clouds identifying features such as the 158 micron C+ line, HD in planetary atmospheres and nonequilibrium molecules.

Aside from astronomy applications, the IR detector market covers a wide range, with a market capitalization of tens of billion dollars. Some of these applications include: 1) defense, 2) non-invasive medical diagnostics, 3) environmental monitoring, 4) industrial process monitoring, and 5) research sector in universities and laboratories. Recently, Fourier Transform Infrared (FTIR) difference spectroscopic techniques have been developed to directly study specific molecular modes in biophysics research. The availability of fast detectors will aid the biophysics community, opening a window where bonds between metals and organic ligands can be investigated, avoiding the difficulties associated with Raman spectroscopy due to fluorescence.