Detector passivated implanted planar silicon

A modem version of the charged particle detector is called PIPS, an acronym for Passivated Implanted Planar Silicon. This detector employs implanted rather than surface barrier contacts and is therefore more mgged and reliable than the Silicon Surface Barrier (SSB) detector it replaces. 

Later, using a similar approach, Gaggeler and co-workers [24-28] at PSI, Villi-gen built the first dedicated setup for isothermal chromatography experiments with short-lived, a- or s.f.-active isotopes of transactinoids. The essential parts of the equipment are shown in Fig. 1.7. A major concern was high efficiency at every step of processing. Several modifications of this OLGA setup have been built and employed. They differed in the parameters of the column and in the complexity, as well as quality, of the detection system. For example, the older detectors were replaced by the passivated implanted planar silicon (PIPS) detectors, which are much more resistant to elevated temperature and to chemicals. 

The prepared alpha sources were counted using passivated implanted planar silicon (PIPS) detectors (Canberra, Belgium, model A450). Counting time was variable depending on sample activity and errors for individual measurements were estimated from counting statistics. 

For this reason, silicon surface barrier (SSB) or passivated implanted planar silicon (PIPS) detectors remain by far the most popular detector option for charged particle measurements. Although the best depth resolution normally attainable with these detectors is of the order of 5 nm, it is srtflicient to quantify the areal density (mg m ) of a polymer bmsh layer adsorbed at a sample surface. Polymer bmshes or polymer molecules have a typical spatial extent of the order of 2-lOrrm. In order to learn more about the bmsh, one really requires the depth resolution to be significantly better than the polymer chain dimensions. In other words, improvements of the depth resolution will need to rival that which is available by NR (-0.3 nm) before they are likely to have any significant impact on polymer science research. 

Egorov, O. B., Addleman, R. S., O Hara, M. J., Marks, T., and Grate, J. W., Direct measurement of alpha emitters in liquids using passivated ion implanted planar silicon (PIPS) diode detectors, Nucl. Instrum. Methods Phys. Res., Sect. A, 537, 600-609, 2005. 

A He(KCl)-jet transportation system was used for the transfer of the activities. The KC1 aerosol with the reaction products was collected by impaction on a Pt or Teflon slip for 60 or 90 s, was picked up with lOpL of the aqueous phase and was transferred to a 1 mL centrifuge cone containing 20 iL of the organic phase. The phases were mixed ultrasonically for 5 s and were centrifuged for 10 s for phase separation. The organic phase was transferred to a glass cover slip, was evaporated to dryness on a hot plate, and was placed over a passivated ion-implanted planar silicon detector (PIPS). This procedure took about 1 min. 

To measure the decay of the separated species, they are - after leaving the chromatographic column and entering a water-cooled recluster chamber - attached to new aerosols and transported through a capillary to a detection system, a rotating wheel or a moving tape system (Tiirler 1996) that positions the deposited activity in front of successive PIPS detectors (Passivated Ion-implanted Planar Silicon), which register a particles and SF events. The... 

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