1. Internal electric-field-lines distribution in CdznTe detectors measured using X-ray mapping
- Author
-
Bolotnikov, A.E., Camarda, G.S., Cui, Y., Hossain, A., Yang, G., Yao, H.W., and James, R.B.
- Subjects
Radiation warning systems -- Properties ,Crystals -- Atomic properties ,Electric fields -- Distribution ,Company distribution practices ,Business ,Electronics ,Electronics and electrical industries - Abstract
The ideal operation of CdZnTe devices entails having a uniformly distributed internal electric field. Such uniformity especially is critical for thick long-drift-length detectors, such as large-volume CPG and 3-D multi-pixel devices. Using a high-spatial resolution X-ray mapping technique, we investigated the distribution of the electric field in real devices. Our measurements demonstrate that in thin detectors, < 5 mm, the electric field-lines tend to bend away from the side surfaces (i.e., a focusing effect). In thick detectors, > 1 cm, with a large aspect ratio (thickness-to-width ratio), we observed two effects: the electric field lines bending away from or towards the side surfaces, which we called, respectively, the focusing field-line distribution and the defocusing field-line distribution. In addition to these large-scale variations, the field-line distributions were locally perturbed by the presence of extended defects and residual strains existing inside the crystals. We present our data clearly demonstrating the non-uniformity of the internal electric field. Index Terms--CdZnTe, crystal defects, radiation detectors.
- Published
- 2009