Heterostructures and Quantum Wells for Imaging Applications
in the Wavelength Spectrum Longer than that of your Camcorder
H.C.Liu
NRC, Canada
We are all familiar with what CCDs can do by playing with our camcorders.
CCDs are excellent imaging devices for the visible light. For wavelengths
longer than what CCDs can cover (longer than about 1 micron), imaging devices
become very expensive. This is the prime reason for the very few
and specialized applications in the long wavelengths. Here we present an
approach to solve this problem using devices that convert long wavelengths
to short wavelengths which are then detected by CCDs. With the development
of epitaxial growth technologies and bandgap engineering concepts in the
last decade or so, heterostructures and quantum wells are expanding the
capabilities of semiconductor devices. We make use of these technologies
and concepts to implement the wavelength conversion device.