A simple method of chromium coating using a ferrotype plate for scanning electron microscopy.

A simple method of chromium coating was developed. A chromium ferrotype plate for drying photoprints was used as a target of a planar magnetron ion-sputter coater. As a result, a high quality chromium film was obtained on dried specimens at room temperature without cooling. The grain size, measuring 1-2 nm in diameter, was small enough for observations of ultrastructures such as F1 particles on the inner mitochondrial membrane. In routine studies under x 100,000, however, chromium coating was not recommended because of its low emission of secondary electrons.