X-ray Peltier cooled detectors for X-ray fluorescence analysis

The recent results on development of X-ray Si(Li), Si-planar and CdTe p-i-n detectors cooled by Peltier coolers for fabrication of laboratory and portable XRF analysers for different applications are discussed. Low detection limits of XRF analysers are provided by increasing of detectors sensitive surface; improvement of their spectrometrical characteristics; decreasing of front-end-electronics noise level; Peltier coolers and vacuum chambers cooling modes optimization. Solution of all mentioned tasks allowed to develop Peltier cooled detectors with the following performances: 1. Si(Li) detectors: S = 20 mm(2), thickness = 3.5 mm, 175 eV (5.9 keV), 430 eV (59.6 keV); S = 100 mm(2); thickness = 4.5 mm, 270 eV (5.9 keV), 485 eV (59.6 keV). 2. Si-planar detector: S = 10 mm(2), thickness = 0.4 mm, 230 eV (5.9 keV), 460 eV (59.6 keV). 3. CdTe p-i-n detectors: S = 16 mm(2), thickness = 0.5 turn, 350 eV (5.9 keV), 585 eV (59.6 keV). S = 16 mm(2), thickness = 1.2 turn, 3 10 eV (5.9 keV), 600 eV (59.6 keV). Advantages and disadvantages of all types of detectors for X-ray fluorescence analysis are compared. Spectra are presented. Application of different XRF analysers based on developed detectors in medicine, environmental science, industry, cryminalistics and history of art are demonstrated. ((C)) 2001 Elsevier Science Ltd. All rights reserved.