ISSN:
1089-7623
Source:
AIP Digital Archive
Topics:
Physics
,
Electrical Engineering, Measurement and Control Technology
Notes:
A facility is described to record the blocking pattern of a single crystal produced by 400 keV protons. By this we aim at a reliable, fast, and careful procedure to align single crystals to the incoming ion beam. The two-dimensional position sensitive detector (2D-PSD) system from Roentdek GmbH Frankfurt/M, Germany, is based on three microchannel plates arranged in a Z stack. The essential shortcoming of this detector is its low sensitivity to high energy (〉200 keV) projectiles. To reproduce the pattern formed by 400 keV protons on the 2D-PSD we had to decrease their energy to a few tens of kiloelectron-volts by a stopping foil of 3.5 μm Mylar®. This foil has the additional advantage of absorbing slow projectiles and sputtered atoms emerging from the target. On their way to the detector, these slow particles, in case they are charged, would be strongly influenced by electric fields and would thus obscure the true pattern. At present, our facility allows us to routinely align crystals for channeling measurements accurately, fast and, for most applications, with an acceptable amount of radiation damage. © 2000 American Institute of Physics.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.1150676
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