Sputter shadowing.

A device has been constructed which allows specimens to be shadowed in a conventional sputter water. This process of sputter shadowing lends to specimens a contrast suitable for imaging in the transmission electron microscope (TEM). The process has the practical advantages over metal evaporation shadowing of lower instrumentation costs, less user training, and less time expenditure per shadowing operation. It provides on a single grid a spectrum of shadowing contrasts from which optimal imaging for a particular specimen can be chosen. The process minimizes radiant and metal deposition heating of the specimen and, thereby, may better preserve its structure during the contrasting procedure. The grain resulting from sputter shadowing differs significantly from that obtained by metal evaporation shadowing and the possibility for using this difference to improve resolution in shadowed preparations is discussed.