The Kore rotating stage is unique in that it allows any part of the sample surface to be analysed whilst maintaining the precise alignment of the rotational and ion optical axes. This is done by ensuring that the linear motions, provided to allow the choice of analysis position , are built as part of the rotating assembly. The drive for the rotating linear xy stage from the fixed flange is via shafts concentric with the axis of rotation, such that the stage can rotate freely without causing movement in the xy motions.
The Kore rotating xy sample stage is designed to retrofit onto all Cameca “f” type Ion Microscopes. The stage completely replaces the standard Cameca sample manipulator, fitting onto the standard manipulator flange, with no alterations to the Cameca hardware.
Rotating the sample improves the depth resolution in high performance dynamic SIMS measurements by minimising the evolution of surface topography. This otherwise develops in one of two ways. On single crystal samples, usually semiconductors, bombardment with an energetic non-normal primary beam causes ripples to develop in the surface. Normal incidence avoids this effect but is not possible in the Cameca IMS.
Very low primary beam energies also help but create problems in spot size and erosion rate. Sample rotation is a more practical method for eliminating this problem. The second mechanism occurs on polycrystalline materials, for example metallisations on semiconductors, where severe surface topography is caused at all incident angles and energies of the primary beam by the different erosion rates of the randomly orientated crystallites. In this case the roughening can be greatly reduced only by the combination of sample rotation and non-normal incidence.
Kore Technology is a centre of excellence in time-of-flight mass spectrometer technology and has a very strong R&D capability in terms of its personnel, all of whom have been heavily involved in a variety of analytical instrumentation development programmes.