High-resolution shadow-casting technique for the electron microscope using the simultaneous evaporation of platinum and carbon

Conventional shadowcasting techniques using heavy metals as shadowing materials suffer from a limited resolution imposed by the granulation of the metal. The paper describes a method for the simultaneous evaporation of platinum and carbon. This produces a deposit which does not granulate but at the same time has the high electron scattering power required for shadowing purposes. The properties of the deposit relating to its suitability as a shadowing material are fully discussed. The method is illustrated by means of various applications, one of which, the cleavage face of a sucrose crystal, exhibits monomolecular steps 11 Å high.