Electron Microbeam / X-Ray Diffraction Facility


The Electron Microbeam/X-ray Diffraction Facility is an integration of three laboratories comprising the following instruments: Cameca SX50 electron microprobe, Philips XL-30 scanning electron microscope/Bruker Quantax 200 energy-dispersion X-ray microanalysis system, and Bruker AXS D8 Focus and D8 Advance X-ray powder diffractometers. Two preparation laboratories with a carbon evaporator unit, micronising mill, spray drier, and other miscellaneous equipment, support these operations.

The electron microprobe, scanning electron microscope and preparation laboratory are housed in a specially-built low-vibration ground-floor laboratory complex with air conditioning and clean-air system; the X-ray powder diffractometers and preparation laboratory are housed elsewhere. Originally independent, these three laboratories have been merged into a modern analytical facility for the comprehensive characterization of minerals and materials. The Facility is managed by a university-paid Research Scientist/Honorary Professor (Mati Raudsepp); support personnel, comprising full-time Research Scientists (Elisabetta Pani, Jenny Lai, Edith Czech), are supported from laboratory revenues.

Clients of the facility include researchers from within the department, numerous other departments at The University of British Columbia, University of Victoria, Simon Fraser University, Western Washington University, Federal and Provincial governments, and a large and diverse private sector - both local and international. In these laboratories, all work is done by the researchers. Graduate and undergraduate students, postdoctoral fellows and faculty are trained not only to operate the instrument but also in all aspects of this method of analysis: analytical strategy, data acquisition, data reduction and interpretation of the results. In addition, the electron microprobe, the scanning electron microscope and powder diffractometers are routinely included as a significant part of a graduate course in the characterization of minerals and materials (EOSC 521) taught by Raudsepp.

Both as a service to the public and to supplement income, the Facility provides analytical services to the private sector. Although quantitative phase analysis using the Rietveld method for exploration/mining, mineral processing and problems of environmental remediation is the major focus, a diverse range of services is also provided for clients from other engineering and technical fields, and from various industries in the high-technology sector.


Electron microprobe

The laboratory is centered on a fully-automated Cameca SX50 Scanning Electron Microprobe with 4 vertical wavelength-dispersion X-ray spectrometers and a fully-integrated SAMx energy-dispersion X-ray spectrometer. One of the spectrometers has two layered dispersion elements (W/Si, Ni/C), which allow the quantitative analysis of the light elements (F, O, N, C, B). There are standards for virtually all of the elements and common alloys. The instrument can produce X-ray element maps from EDS or WDS spectrometers, backscattered electron images, and secondary electron images.

Scanning electron microscope

A Philips XL30 electron microscope (Bruker Quantax 200 energy-dispersion X-ray microanalysis system, XFlash 6010 SDD detector, Robinson cathodoluminescence detector) shares the clean lab with the microprobe, and allows quick examination and digital imaging of minerals and materials at both low and high magnifications using secondary electrons, backscattered electrons, characteristic X-rays, and cathodoluminescence signals.

X-ray powder diffractometer

Bruker D8 Focus (0-20, LynxEye detector) and D8 Advance (0-0, LynxEye XE detector) diffractometers allow quick collection of diffraction data for the characterization of single mineral powders or mixtures of minerals from whole-rock powders. Diffraction data may be processed by automated 'search-match' software which makes use of the International Centre for Diffraction Data PDF-4+ database. The diffraction data may be output as colour-coded diffraction profiles, reflection lists, or as raw data files, or in ASCII format for additional user manipulation. Quantitative phase analysis of mixtures using the Rietveld method may be done using Bruker Topas software.