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Initial testing of a Si:As blocked-impurity-band (BIB) trap detector



Solomon I. Woods, Simon G. Kaplan, Timothy M. Jung, Adriaan C. Carter, James E. Proctor


We discuss the design, construction, and initial test results of a Si:As blocked-impurity-band (BIB) trap detector. The trap consists of two rectangular BIB devices configured in a v-shaped geometry. This trapping geometry is designed to ideally yield a minimum of 7 bounces before exit for incident light within an f/4 cone with 3 mm clear aperture. The individual BIB devices consist of 70 µm thick active layers with As doping near 1.7x10^18 cm^-3, and have dark currents of approximately 100 nA at an operating temperature of 9 K. A simple ray-tracing model of the trap, along with data on the quantum yield of typical BIB detector elements, indicates that it is possible to achieve an external quantum efficiency of > 0.99 over the 4 µm to 28 µm spectral range and significant suppression of the etalon fringes present in the spectral responsivity of a single element. We have made initial responsivity measurements of the trap compared to a calibrated 5 mm diameter pyroelectric detector over the 3 µm to 17 µm spectral range using the fiber-coupled output of a Fourier-transform spectrometer. We also discuss the results of comparison measurements between the trap detector and an absolute cryogenic radiometer viewing the output of a calibrated blackbody source at discrete filter bands from 5 µm to 11 µm. In initial testing the performance of the trap is limited by the poor performance of the individual BIB detectors, but the advantages of boosted quantum efficiency and suppressed etalon are realized by the trap.
Proceedings Title
Proceedings of SPIE
Conference Dates
April 23-27, 2012
Conference Location
Baltimore, MD
Conference Title
SPIE Defense, Security & Sensing


BIB detector, blocked-impurity-band detector, trap detector, infrared detector, long wavelength IR detector, far infrared detector, detector calibration


Woods, S. , Kaplan, S. , Jung, T. , Carter, A. and Proctor, J. (2012), Initial testing of a Si:As blocked-impurity-band (BIB) trap detector, Proceedings of SPIE, Baltimore, MD, [online], (Accessed May 29, 2024)


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Created October 31, 2012, Updated February 19, 2017