Electron Channeling Analysis and Z-C0ntrast Imaging of Dopants in Semiconductors

Abstract

The determination of dopant distribution and lattice location are key elements in the characterization of ion-implanted, thermally processed semiconductors. We present here two analytical techniques for this purpose. The first is a channeling technique for the determination of substitutional fractions of dopants or impurities in any crystal structure, and the second is a means for imaging and elemental mapping of heavy elements in light materials, even if they are in solution.Atom Location by Electron Channeling AnalysisIt has only recently been realized that the orientation dependence of characteristic x-ray emission close to a Bragg reflection, long regarded as a hindrance to accurate microanalysis, can form the basis of a powerful lattice location technique. The first studies of this kind located trace elements in layer structure minerals, where it was known that the only possible sites for the impurity lay within the layer planes A and/or B. These restraints exclude many materials and here a generalization to any crystal structure is described.