Microtomy for SPM

Some SPM techniques require a very flat specimen, which is best produced by microtomy. The quality of information from an ultramicro-tomed surface provides a specimen with no smearing and minimum surface roughness. Microtome manufacturers, such as Leica, have produced special AFM sample holders to aid preparation of specimen faces free from artifacts. These holders allow clamping of the spec- 

Striations or lines in the section Nicks in knife edge hard particles or contaminants Change knife or knife edge used for cutting 

Section thickness is not uniform Knife angle too low block hard temperature not correct for specimen Adjust knife angle choose correct temperature retrim to improve shape 

Sections compressed or wrinkled Knife not sharp or clean knife angle not correct sectioning speed too fast Exchange knife or change cutting zone cool block thin sections require slow cutting speed 

Sections do not form ribbons Specimen block may be too cold inclination angle too large too thick or knife blunt Increase temperature of block, expose it to light adjust knife angle select thinner sections exchange knife or cutting zone 

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