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Development of Uniform CdTe Pixel Detectors Based on Caltech ASIC

K. Oonuki·H. Inoue·K. Nakazawa·T. Mitani·T. Tanaka·T. Takahashi·C. M. H. Chen·W. R. Cook·F. A. Harrison
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Abstract

We have developed a large CdTe pixel detector with dimensions of 23.7 x 13.0 mm and a pixel size of 448 x 448 um^2. The detector is based on recent technologies of an uniform CdTe single crystal, a two-dimensional ASIC, and stud bump-bonding to connect pixel electrodes on the CdTe surface to the ASIC. Good spectra are obtained from 1051 pixels out of total 1056 pixels. When we operate the detector at -50 C, the energy resolution is 0.67 keV and 0.99 keV at 14 keV and 60 keV, respectively. Week-long stability of the detector is confirmed at operating temperatures of both -50 C and -20 C. The detector also shows high uniformity: the peak positions for all pixels agree to within 0.82%, and the average of the energy resolution is 1.04 keV at a temperature of -50 C. When we normalized the peak area by the total counts detected by each pixel, a variation of 2.1 % is obtained.

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K. Oonuki, H. Inoue, K. Nakazawa, T. Mitani, T. Tanaka, T. Takahashi, C. M. H. Chen, W. R. Cook, F. A. Harrison. 2004-10-02. Development of Uniform CdTe Pixel Detectors Based on Caltech ASIC. https://doi.org/10.1117/12.552598

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