AN EFFICIENT X-RAY WAVELENGTH SPECTROMETER FOR IMPROVED ELEMENTAL ANALYSIS ON THE ANALYTICAL ELECTRON MICROSCOPE

A NEW TYPE OF WAVELENGTH DISPERSIVE (WD) X-RAY SPECTROMETER IS PROPOSED. ITS ANTICIPATED ATTRIBUTES OF HIGH EFFICIENCY AND SMALL PHYSICAL SIZE MAKE IT SUITABLE FOR USE ON ANALYTICAL ELECTRON MICROSCOPES (AEMS), WHERE CURRENT WD SPECTROMETERS ARE GENERALLY INAPPROPRIATE. PRELIMINARY CALCULATIONS INDICATE THAT THE EFFICIENCY OF THE NEW DEVICE SHOULD BE, AT LOW ANGLES, ABOUT EQUAL TO A 200MM ROWLAND CIRCLE BRAGG SPECTROMETER FOR THE SAME CRYSTAL; AT HIGH ANGLES, THE NEW DEVICE MAY BE UP TO 1000 TIMES MORE EFFICIENT. COMPARED TO ENERGY DISPERSIVE (ED) SPECTROMETERSCOMMONLY USED ON AEMS, THE PROPOSED WD SPECTROMETER SHOULD PROVIDE MORE SENSITIVE ANALYSIS, PARTICULARLY FOR THE LIGHT ELEMENTS (WITH ATOMIC NUMBERS LESS THAN 10).