Analysis of Crosstalk in HgCdTe based Vertical Photoconductive LWIR Detector Arrays

• Main Authors: Prachi Mohan KULSHRESTHA, Raghvendra Sahai SAXENA, Risal SINGH
• Format: Article
• Language: English
• Published: IFSA Publishing, S.L. 2013-07-01
• Series: Sensors & Transducers
• Subjects: Crosstalk analysis; HgCdTe; Infrared; LWIR detectors; Photoconductive detector.
• Online Access: http://www.sensorsportal.com/HTML/DIGEST/july_2013/P_1261.pdf

HgCdTe is a well known material for Infrared detection applications because of its special properties like high absorption coefficient, adjustable bandgap and moderate dielectric constant etc. Vertical PC detectors of HgCdTe are very easy to fabricate as compared to the other detectors with the desired uniformity and therefore, these detectors may be proved better choice if the cost and the yield are considered. The proposed vertical PC detector design improves the fill factor of the detector array and allows the access of individual elements without the need of integrated circuit for their readout. The structure virtually does not have any optical crosstalk due to diffusion current, but suffers from the electrical crosstalk because of the networking of its element. This paper presents an analysis of the crosstalk for the focal plane array (FPA) of vertical PC detectors. We demonstrate that the networking reduces the detectivity by a factor strongly dependent on the number of rows and columns in the FPA.