Preparation of submicron cobalt films using cobalt oxalate as a precursor

The possibility of obtaining porous two-dimensional cobalt structures (films) with submicron thickness using cobalt oxalate as a precursor during heat treatment in a hydrogen flow has been established. It is shown that the formation of two-dimensional structures on liquid low-melting metals (In, Ga) allows avoiding the formation of cracks and increases the integrity of Co films. It is shown that the thickness of Co films on Si reaches 100 nm, but the linear size of such cobalt sheets does not exceed 20 microns. The use of low-melting indium as a substrate makes it possible to increase the average size of Co films compared to Co films on silicon without an intermediate indium layer. The material is a thin two-dimensional layered structure of porous cobalt formed by interlacing metal chains. The film thickness is ~ 500 nm, and the linear size reaches 200 microns. The possibility of obtaining a durable metal film of Co-10% Ga on a massive drop of gallium measuring 20x15 mm has been established.