History & Facilities
The Electron Microprobe Laboratory (EMPL) was established in 1988 through a grant from the U.S. Department of Energy (#DE-FG22-87FE1146). It was initially built around a CAMECA SX50 electron probe microanalyzer that was the second such instrument in the world, and first in North America, to have a maximum configuration with five wavelength-dispersive spectrometers. In August-September of 1995 upgrades to computer automation, backscattered electron detection system, and imaging systems were accomplished via a National Science Foundation grant (#EAR-9404658), with matching funds supplied by the University of Oklahoma Vice President for Research and from user fees accrued by the laboratory. Further upgrades to the computing systems, Energy-Dispersive X-ray Analyzer automation, digital image capture system, display monitors, and printers were made in the first half of 1999, again via funds from OU VPR and accrued user fees. The GATAN cathodoluminescence detector was added in June, 2000, made possible from by funds from the OU VPR. The sample stage was replaced in 2004 with funds from a National Science Foundation grant (#EAR-0124179). Further upgrades to the computer automation, image and EDXA acquisition systems, and other hardware components within the microprobe were enabled by a 2007-2008 National Science Foundation grant (#EAR-0649001), with additional funds furnished by the University of Oklahoma Vice President for Research.
The SX50 was retired from service in March of 2015 in favor of a newer CAMECA SX100 that was obtained by donation from Sandia National Laboratory through the Department of Energy’s Laboratory Equipment Donation Program. Installation and automation of this instrument, including updating the Energy-Dispersive X-Ray Analyzer to a system based on a new silicon drift detector, was supported by funds from a National Science Foundation grant (#EAR-1401940) and, again, by generous support of the University of Oklahoma’s Vice President for Research. The new instrument is also a five-WDS machine with configuration that provides even greater flexibility for light element analysis and greater sensitivity for many trace elements than the previous system. The cathodoluminescence detector, developed as a prototype for the SX50, was transferred to the SX100.
The EMPL occupies three rooms on the lower level of Sarkeys Energy Center, comprising a total area of near 1000 ft2. The microprobe itself is situated in a spacious room (#E106) of nearly 600 ft2. Controlled atmosphere and dedicated uninterruptable power supply provide a superbly stable operating environment year-round. Complete sample preparation facilities, including grinding and polishing equipment, binocular microscope, and research grade petrographic microscope are available in the adjoining laboratory. Support equipment (rotary mechanical vacuum pumps and the dedicated water chiller for the microprobe) are located in the adjoining sample preparation laboratory and in a nearby equipment room, to minimize noise, vibration, and excess heat around the microprobe itself. Throughout its existence, operation of the facility has graciously been supported by the Office of Research Administration at the University of Oklahoma.