ENERGY FILTERED DETECTOR FOR MICRO-DIFFRACTION IN THE SEM

MICRO-DIFFRACTION-BASED CRYSTALLOGRAPHY IS ESSENTIAL TO MATERIALS DESIGN AND PROCESS UNDERSTANDING IN KEY INDUSTRIAL APPLICATIONS SUCH AS MICROELECTRONICS, SUPERCONDUCTIVITY, SOLAR ENERGY, STRUCTURAL COMPOSITES, AND METAL FORMING. THE SCANNING ELECTRON MICROSCOPE (SEM) CAN PROVIDE HIGH SPATIAL RESOLUTION CRYSTALLOGRAPHIC INFORMATION, BUT ITS APPLICABILITY IS LIMITED BY THE LOW SENSITIVITY OF EXISTING TECHNIQUES. THE CURRENT METHODOLOGY CANNOT BE EASILY USED FOR DOSE-SENSITIVE MATERIALS, ELECTRICAL NONCONDUCTORS, AND SAMPLES WITH EVEN SMALL AMOUNTS OF SURFACE DAMAGE. THE DIFFICULTY OF OBTAINING MICRODIFFRACTION DATA IS A DRAWBACK IN THE SEM, WHICH OTHERWISE IS USEFUL IN OBTAINING HIGH RESOLUTION TOPOGRAPHICAL AND COMPOSITIONAL INFORMATION, AND USUALLY REQUIRES MINIMAL SPECIMEN PREPARATION. THE PROJECT IS DETERMINING THE FEASIBILITY OF EMPLOYING AN ENERGY FILTERING DETECTOR WITH HIGH GAIN TO INCREASE THE SENSITIVITY OF MICRO-DIFFRACTION IN THE SEM. THE FILTER IS BEING APPLIED TO BACKSCATTERED ELECTRON PATTERNS THAT PROVIDE CRYSTALLOGRAPHIC INFORMATION AT VERY HIGH SPATIAL RESOLUTION. THE STUDY REQUIES AN AMPLIFYING ELEMENT THAT IS SENSITIVE TO LOW ENERGY ELECTRONS, SUCH AS A MICROCHANNEL PLATE. THE RESEARCH IS TESTING THE OVERALL FEASIBILITY OF HIS APPROACH AS WELL AS THE SPECIFIC ISSUES OF DYNAMIC RANGE AND NOISE LEVEL. EXPLOITATION OF THE RESEARCH WOULD IMPROVE THE COMPETITIVE POSITION OF DOMESTIC INDUSTRIES BY ENHANCING THEIR CAPABILITY TO IDENTIFY COMPONENTS AND DEFINE AGGREGATE PROPERTIES RELATED TO ADVANCED MATERIALS AND PROCESSES. IN ADDITION, IT WOULD EXTEND THE FUNCTIONALITY OF A LARGE EXISTING BASE OF SCANNING MICROSCOPES USED IN ACADEMIC AND INDUSTRIAL RESEARCH.