Project Title:

Strained Type II Superlattice Infrared Detectors

08.09-1929
900728
Strained Type II Superlattice Infrared Detectors

Abstract:

1. Concept Description:  To address problems associated with detectors and detector
arrays in the infrared wavelength range, we propose to investigate the optical properties
of a recently invented class of type II strained-layer superlattices made of (Ga,As)
related compounds. The new concept has advantages compared with previous efforts
in that small bandgaps may be achieved with sufficiently thin repeating layers in
the superlattices so that they have good optical absorption properties and favorable
electrical transport properties original calculations have indicated Ga1-xInxSb/InAs
to be the best choice for such application. Very recently it has been show to have
the highest absorption coefficient at 10um wavelength compared to all other superlattice
materials. To explore the potential of this material system, we will fabricate these
structures. 2. Project Objectives:  To fabricate optimized detector structures according
to theoretical model and evaluate their infrared optical properties. 3. Project Description
and Anticipated Results:  We propose to fabricate them by molecular beam epitaxy
(MBE) according to structural parameters determined from theoretical modelling. The
sample will be characterized optically and evaluated for infrared detection applications
in the 2-17um region.
The very favorable optical properties of the strained-layer type II superlattices
suggest that they could be very useful for infrared detectors and detector arrays
used in space astronomy, physics and atmospheric studies, as well as medical and
industrial thermal imaging applications.
infrared, detector, strained-layer type II superlattices, MBE