Purchased in December 2014, the JEOL JXA 8530F Hyperprobe was delivered in August 2015, was fully installed in December 2015 and it is managed by Dr. Gelu Costin (Gabi). The funding for the new equipment was entirely provided by Rice University.

The Jeol JXA 8530F Hyperprobe it is a fully-automated electron microprobe, customized for various EPMA applications. It has a digital imaging capability and can acquire digital backscattered images (in compositional and topographic modes), as well as secondary electron images. High resolution digital X-ray intensity (element distribution) maps can be acquired using stage (for large maps) or beam (for small maps) scanning mode.

The Jeol JXA 8530F is equipped with a field emission gun (Schottcky Field Emission Source), five wavelength dispersive spectrometers (WDS) and an integrated EDS detector. The spectrometer #1 has four analyzing crystals, while the spectrometers #2, #3, #4 and #5 have two analyzing crystals, each. Spectrometer #3 is an H-type, with 100 mm radius of the Rawland circle, giving ~ three times higher count rates compared with an XCE spectrometer. The spectrometer #5 is a L-type, with large analyzing crystals (PETL, LiFL), suitable for trace element analysis, giving high X-ray intensities (without sacrificing the peak/background ratio), and higher spectral resolution. The customized configuration of the five spectrometers and the element range for each analyzing crystal are shown below.

Spectrometer Type Counter Analyzing crystals
#1 FCS GPC TAPJ, LDE2, PETJ , LDEB
#2 XCE XPC LiF , PETJ
#3 H XM-86XPCH PETHS, LiFHS
#4 XCE GPC LDE1, TAPJ
#5 L XPC PETL, LiFL

 

Analyzing Crystal

Element Range

LDE1

Kα lines of C, N, O, and F

LDE2

Kα lines of B, C, and N

LDEB

Kα lines of Be and B

TAPJ

Kα lines O – Si
Lα lines Cr – Zr
Mα lines La – Pt

PETJ, PETH, PETL

Kα lines Si – Cr
Lα lines Kr-Eu
Mα lines Lu – Bi and Th – U

LIF, LIFH, LiFL

Kα lines of Ca – Rb
Lα lines of Sb – U

The EDS detector is a Silicon Drift X-ray Detector, with a 10mm² active area, 133eV resolution. Detection ranges from Boron through Uranium.

 

Spectrometers #1 and #4 use proportional gas flow counters. The gas used is P-10 (90% Argon – 10% Methane mixture) that is optimum for low energy X-ray detection. The spectrometers #2, #3 and #5 use sealed Xenon counters for detection of higher energy X-ray photons.

 

Note! The element analytical lists are set up in advance for most routine materials, and judgement based on experience is used to select a particular x-ray line and crystal for a given application. This is why the operator needs to know the application before judging the setup of the microprobe (beam current and size, standards to be used, X-ray lines, backgrounds etc).

Other features of the JXA 8530 F are:

 

  • Integrated visible- reflected light microscopy at 400 x magnification
  • Auto-focus system for optimal sample positioning
  • Secondary electron detector
  • Backscattered electron detector (annular solid state type for compositional and topographical imaging)
  • Magnification range 40X to 300,000X (144 steps)
  • Specimen exchange for up to 100mm diameter x 50mm samples
  • Computer automation operating through PC compatible JEOL software on a Windows Windows7 platform.

Our lab uses the Virtual WDS registered software (® Cambridge University) for simulation of X-ray peaks, backgrounds, interferences and strategy of X-ray counting.

A new JEE-420 vacuum evaporator is used for carbon coating of various types of samples.

After a basic training and a first supervised EPMA session, the users are encouraged to work independently (unsupervised).  Even during unsupervised sessions, the assistance is available, at any time during the workday. The users are encouraged to ask for assistance any time they might need. For urgent assistance during the overtime EPMA sessions (overnight, weekends, and public holiday) please contact the lab manager at the contact number which will be provided.

Capabilities

  • Full quantitative analysis. All detectable elements (from Be to U) are quantified on a spot of ca.100 nm to 1μm diameter or larger. Detection limits range 30-100 ppm, depending on the element and settings.
  • Rapid qualitative analysis, in EDS or WDS mode and phase identification
  • Line analyses (rapid compositional profiles)
  • High resolution chemical mapping (in WDS or integrated WDS-EDS mode) of specimens on scales from hundred nm to ca 8 cm
  • Imaging specimens at micro-scale using backscattered electron (BSE) and secondary electron signal
  • Topographic imaging for unpolished samples

Standards

Our current mineral standard collection includes natural minerals and synthetic glasses and metals, from various sources: SPI Supplies, Agar Scientific, Smithsonian, Rhodes University, University of Arizona and others (Rice_EPMA_standards). Our EPMA standards collection is constantly growing, as more standards become available and mounted.