Nineteen-element high-purity Ge solid-state detector array for fluorescence X-ray absorption fine structure studies

We describe a 19-element high-purity Ge solid-state detector array developed for high-throughput fluorescence X-ray absorption fine structure (XAFS) experiments in ultra-high vacuum (UHV). The packing ratio is 57%, a significant improvement over that of standard 13-element arrays (37%). The average energy resolution in the 19 channels is similar to 170 eV at 5.9 keV with an amplifier shaping time of 6 mu s. The detector array can be used up to a count rate of 200 kcps per channel using a shaping time of 0.5 mu s and a dead-time correction. A total count rate of 3.8 x 10(6) cps is obtained with an energy resolution of 240 eV. Capability of the new detector for fluorescence-detected XAFS applications is demonstrated for 1000 Angstrom thick YBa2Cu3O7 on SrTiO3 substrate and similar to 0.1 monolayer of As atoms on an InP(001). (C) 1998 Elsevier Science B.V. All rights reserved.