Specimen preparation for scanning-probe microscopy of materials by ultramicrotomy

Abstract

Scanning Probe Microscopy (SPM) has been traditionally employed for the characterization of exposed and naturally occurring surfaces. An extension of the technique for studying the bulk properties of materials is limited by the ability to produce and expose a perfectly clean, defect-free, smooth, flat surface within the body of the sample. With the exception of monocrystals with a preferred cleavage plane, most materials for SPM bulk examination have been prepared using conventional lapping procedures. Generally, as a result of surface scratches or residual lapping debris, a surface prepared in such a way is not sufficiently smooth or clean for its intended application. In addition, such a sample is not representative of the bulk material due to the surface defects commonly caused by the use of abrasives. In the case of particulate materials these difficulties are compounded by the need to support and immobilize the particles and generate a sufficiently large surface for SPM.