Adachi K, Hojou K, Katoh M, Kanaya K
Ultramicroscopy. 1976 Dec;2(1):17-29. doi: 10.1016/s0304-3991(76)90212-6.
The sputtering process by an ion beam well collimated and highly accelerated provides a valuable means of high resolution shadowing, replication of a fine object by a combination of pre-shadowing and deposition as well as a preparation of supporting films. High resolution shadowing and films with grains smaller than 1 nm can be obtained by argon ion-sputtering targets of tungsten and tungsten/tantalum alloy. The resolution of carbon replicas pre-shadowed with tungsten/tantalum is determined from the radius of curvature of replicated magnesium oxide crystal corners.