Solid-state energy-dispersion spectrometer for electron-microprobe x-ray analysis.

Improved lithium-drifted silicon solid-state detectors allow detection and energy dispersion of x-rays of about 3 to 30 kiloelectron volts in the electron-microprobe x-ray analyzer. Energy resolution is sufficient to separate peaks of characteristic x-rays of elements adjacent in the periodic system at atomic number 20 and higher. The detected x-ray spectrum emitted from an unknown sample can be recorded with a multichannel analyzer in approximately 60 seconds.

Image-formation technique for scanning electron microscopy and electron probe microanalysis.

A technique is described for topographic images on the scanning electron microscope and the scanning electron probe microanalyzer. In this technique, the brightness of the oscilloscope is modulated by a signal obtained by mixing the signal (from secondary electrons or targets current) with its first derivative. This enhances minor topographic features which are poorly reproduced in the technique.

The accuracy of quantitation in X-ray microanalysis, particularly of biological specimens.

The accuracy of results of microanalytical analyses depends on errors in the measurement, separation of the signal from interferences such as background, the quality of the theoretical assumptions underlying the evaluation process, the accuracy of constants and parameters used in the evaluation, the propagation of errors through the evaluation, the quality of the reference standards, the preparation of the specimen before analysis, and the damage inflicted upon it during analysis. The meaning of the results in turn is closely related to the manner in which they expressed, and to the localization which can be achieved in microprobe analysis. The latter aspect includes the capability of the operator to orient the exciting beam towards the topographic features of interest on the specimen.