[en] Three techniques were investigated for identifying microregions of the sample examined by an ion beam during analysis. First, the feasibility of obtaining topographic information by detecting bursts of secondary electrons as individual ions strike the sample was studied. The efficiency of detection was sensitive to sample/detector geometry and to detector operation parameters. Second, the author wanted to determine the location where each ion passed through the sample by detecting the ions with a phosphor coupled with a position sensitive detector. Initially, he used a photomultiplier tube (PMT) to detect light from the phosphor. The PMT was sufficiently sensitive both to detect the light emitted upon bombardment of the phosphor by a single ion and to provide a start signal for particle-induced desorption time-of-flight mass spectroscopy. Third, two track recording materials for locating where the ions passed through the sample were evaluated. The polycarbonate track detector recorded the integrated beam spot image, which was revealed with post-analysis etching and SEM observation. The fluorophlogopite track detector recorded tracks which could be observed by TEM without etching

[en] The objective of this project is to develop and evaluate ion induced desorption mass spectrometry for microscopic analysis. Briefly, the interaction of a microbeam (1-50μm diameter) of high energy heavy ions (84 MeV Kr⁺⁷) with the target surface desorbs and ionizes atoms and molecules. The desorbed ions are analyzed via time-of-flight mass spectrometry to determine the composition of the area addressed with the microbeam. An account of recent work is summarized