Nuclear Instruments and Methods in Physics Research A 509 (2003) 47–51 A comparison of the X-ray performance of TlBr crystals grown by the Bridgeman–Stockbarger and travelling molten zone methods V. Gostilo a, *, A. Owens b , M. Bavdaz b , I. Lisjutin a , A. Peacock b , H. Sipila c , S. Zatoloka a a Baltic Scientific Instruments, Ganibu dambis 26, P.O.Box 33, LV-1005 Riga, Latvia b Science Payload Technology Division, ESA/ESTEC, Postbus 299, 2200AG Noordwijk, The Netherlands c Metorex Int. Oy, P.O.Box 85, FIN-02631 Espoo, Finland Abstract We have investigated at optimal temperature the X-ray detection characteristics of two TlBr crystals by the Traveling Molten Zone (TMZ) technique. The resistivities were typically 1.5  10 10 O cm at room temperature, increasing to (1.1–1.7)  10 12 O cm at 15  C. In the temperature range 0  C to 50  C, both crystals exhibited mobility-lifetime products of B8  10 5 cm 2 V 1 and B1.5  10 5 cm 2 V 1 , for electrons and holes respectively. From these crystals, two detectors were packaged and X-ray metrology carried out. For the best detector, the measured energy resolutions at an operating temperature of 15  C and 500 V bias were 1.0 keV at 5.9 keV; 1.1 at 13.9 keV; 2.5 at 59.54 keV; 3.3 keV at 88 keV; 4 keV at 122 keV and 27.7 keV at 662 keV.A comparative analysis of the characteristics of detectors grown by TMZ to those grown by the Bridgeman–Stockbarger method is given. r 2003 Elsevier Science B.V. All rights reserved. PACS: 07.85Nc; 29.40Wk; 81.05Dz Keywords: Compound semiconductors; TlBr; X-rays Introduction TlBr has attracted considerable attention as an exceptional radiation detector medium [1–3]. Its high effective atomic number (B58), ensures excellent stopping power for hard X- and gam- ma-radiation and due to its high band gap (2.7 eV) its operation requires no or only modest cooling. At room temperature, energy resolutions of 3.3 keV at 60 keV have been achieved [3]. At the present time, it is apparent that detector perfor- mances are largely influenced by crystal growth techniques, which determine the stoichiometric and crystallographic qualities of the initial crystals [2], coupled with detector design and fabrication techniques. Technological improvements in these two key areas are essential for the future develop- ment of TlBr radiation detectors. In a previous paper [3], we presented spectro- scopic results for monolithic and pixel X- and ARTICLE IN PRESS *Corresponding author. Tel.: +371-738-3947; fax: +371- 738-2620. E-mail address: bsi@bsi.lv (V. Gostilo). 0168-9002/03/$-see front matter r 2003 Elsevier Science B.V. All rights reserved. doi:10.1016/S0168-9002(03)01547-X