Typical SHRIMP IIe flat-bottomed sample pit
Small size of standard SHRIMP Samples
Ion Beam Path for SHRIMP IIe
SHRIMP IIe Single Collector, with electron multiplier and Faraday cup
SHRIMP IIe Multicollector - completely reconfigurable under vacuum
Features
Primary Ion Beam
- Independent control of primary and extracted beam energies and polarities.
- 45 degree angle primary beam incident angle for efficient Sputtering of sample.
- Hollow cathode duoplasmatron ion source designed at Cambridge University (UK) especially for ion probe applications - dual polarity - exceptionally bright and stable.
- Option of Cesium gun for analysis of oxygen and electron gun for source neutralisation.
- Wien filter for mass filtering of primary ion beam - adjustable resolution - may be turned off to maximize sputtering rates.
- Kohler focussing provides radially ion flux on the primary beam.
- Beam diameter variable from 5µm to 30µm.
- Beam diameter and brightness adjusted independently.
- Sharply defined, flat-bottomed pits.
Sample Stage
- Standard 25mm diameter sample mounts - Thin section holder or large diameter mega-mount options.
- Fully automated sample transfer.
- Total computer control of sample stage movements - Multiple sample coordinates can be stored and revisited.
- Visual optics permit viewing of sample stage during analysis - Variable magnification - Colour CCD camera/video monitor.
- Up to three samples at one time can be stored in the vacuum lock In addition, two more samples can be placed in the specimen chamber, allowing for the easy comparison of a standard with an unknown.
Seconday Ion Beam
- 90 degree angle extraction of the secondary beam to minimise instrumental discrimination.
- Large apeture eliminates sample-to-sample memory Low field gradient extraction minimizes inter-element discrimination.
- Triple quadrupole lens matching of secondary beam for maximum transmission.
- Simultaneous collection of secondary and mass analysed beams for maximum precision of analysis.
- Large (1272 mm) radius electrostatic analyser.
- Rotatable source slit, width continuously variable from 5µm to 150µm.
- Isotopic mapping of samples accomplished by rastering sample beneath primary beam.
- Elegant, simple integrated ion lens system minimizes beam abberations and simplifies operation.
- High mass dispersion achieved with large (1000mm) radius sector electromagnet.
- Very stable, high speed laminated electromagnet controlled by multiple Hall Effect probes
- Resolution > 5000 (1% definition) with flat-tops for 80µm source slit and 100µm collector slit.
- Sensitivity better than 18cps/ppm/206Pb/nA 02- under above conditions
Single Collector
- Rotatable collector slit, width continuously variable from ~5µm to 300µm.
- Ion counting with robust, high gain, high speed electron multiplier, or
- Ion current measurement via Faraday cup and electrometer.
- Advanced, low-noise electrometers, with computer-configurable gain and settling time.
Multi-Collector (option)
- Five channels of Faraday cups or electron multipliers.
- Fully reconfigurable under vacuum; no lost time in re-pumping.
- Most variables adjustable under computer control (slit size, head spacing, focus).
Instrument Control
- PC platform standard.
- Entire vacuum system under microprocessor control.
- Highly intuitive, easy-to-use graphically orientated operation of entire machine.
- Remote operation via the web, allowing monitoring or real-time control.
- Optional Automated operation for unattended operation and sample pre-screening.