Description:
The given invention features a novel device for bolometric sensing of
incident mid and far IR radiation. The technology employs a freestanding
entangled 2-dimensional network of single walled carbon nanotubes (SWCNT). Such
suspended SWCNT networks have a large bolometric response over a wide
temperature range, including room temperature. They have a high absorption
coefficient, high temperature coefficient of resistance, and extremely low
thermal mass. As a result of these properties, the networks have a dramatically
fast temporal response, which gives this technology excellent potential as a low
cost, uncooled IR detector element. Current sensor technologies involve the use
of an individual nanotube, however discrepancies from one nanotube to the next
make scaled-up production of such devices impossible. The given technology
provides this ability to mass produce while retaining a statistically equivalent
response level. Furthermore, by utilizing selective removal of a sacrificial
oxide layer to form a resonator cavity under the nanotube network, complicated
and expensive multistep lithography is avoided.
Frame rates in excess of 10 kHz are conservatively expected with SWCNT
microbolometers. This substantial improvement expands the application domain of
the proposed microbolometers to image fast changing scenes, with in turn
improves situational awareness.
ADVANTAGES
- Frame rates in excess of 10 kHz
- Faster response and shorter residual image hold than is achieved with
current methods due to extremely low thermal mass and thermal conductivity
- Sensitivity comparable or superior to that of conventional Si or VOx
bolometers due to high absorption coefficient and high temperature coefficient
of resistance(TCR)
- Reduction in cost from current systems by using a single-step removal of a
sacrificial oxide layer as opposed to multi-step lithography used in
conventional microbolometer fabrication
- Mass production potential
APPLICATIONS
The technology has potential applications in infrared cameras, imaging
equipment, and detectors.These applications may be highly useful in the defense
industry, e.g. missile detection, as well as the aerospace and medical
industries.
STATUS OF INTELLECTUAL PROPERTY
US utility patent and Canadian national phase PCT applications have been
filed for this technology.
Himanshu Jain's Lehigh Page