Session X36: Advances in Instrumentation and Measurements
8:00 AM–11:00 AM, Friday, March 14, 2008
Morial Convention Center Room: 228
Sponsoring Unit:
GIMS
Chair: Charles Agosta, Clark University
Abstract ID: BAPS.2008.MAR.X36.9
Abstract: X36.00009 : Intra-valance transitions for uncooled short wave infrared detection
9:36 AM–9:48 AM
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Abstract 
Authors:
A.G. Unil Perera
(Georgia State University)
S.G. Matsik
(Georgia State University)
P.V.V. Jayaweera
(Georgia State University)
H.C. Liu
(National Research Council Canada)
M. Buchanan
(National Research Council Canada)
An infrared detector based on p-GaAs/AlGaAs heterojunction exhibiting response in the 2-5 $\mu $m range at room temperature is demonstrated. The basic principle of the detector utilizes inter-valance (heavy hole, light hole, and split-off hole) absorption of a highly p-doped GaAs layer (emitter). The dark current is limited by the work function at the interface between the highly doped emitter and the undoped Al$_{x}$Ga$_{1-x}$As barrier. The barrier height can be tailored by varying the Al fraction to obtained the desired operating temperature. The split-off energy of the material determines the split-off threshold and the band offset determines the free carrier threshold for the photo excited carriers. Detector performance can be controlled by varying these two thresholds. A device consisting of 30 periods of 3$\times $10$^{18}$ cm$^{-3}$ p-doped GaAs emitter and Al$_{0.57}$Ga$_{0.43}$As barrier regions between two contact layers shows infrared detection up to 330 K with a peak responsivity of 1.4 A/W and D* of 2.6$\times $10$^{9}$ Jones at 2.5 $\mu $m . Different materials should give rise to different wavelength threshold infrared detectors operating at high temperatures.
To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2008.MAR.X36.9