a Atominstitut der Österreichischen Universitäten, Stadionallee 2, TU Wien, Wien 1020, Austria
b Wacker Siltronic AG, BurghausenD-84479, Germany
Abstract:
TXRF is routinely used and suited to inspect Si wafer surfaces for possible impurities of metallic elements at the level of pg and below. Lightweight, compact sized, high-resolution Silicon drift detectors (FWHM=148 eV at 5.9 keV) electically cooled and with high throughput are ideally as the new spectrometer and for clean room application. A KETEK 5 mm2 Si drift detector was compared with a NORAN 80 mm2 SiLi in a previously commercially available ATOMIKA 8010 wafer analyzer. Results are presented and show that almost the same detection limits for both detector types were achieved analyzing a droplet sample containing 1 ng Ni on a Si wafer. Also, the performance to detect low Z elements like Na, excited with monochromatic Cr K radiation in a vacuum chamber was tested and detection limits of 600 pg obtained.