Tantalum can be used for high resolution FE-SEM coating and like most refractory and high melting materials it will give a fine sputtered grain size. Tantalum is similar to chromium in that it oxidises quite rapidly. It has low sputtering rates, but due to its high atomic number SE yield tends to be higher. Because of oxidation issues specimens must be imaged immediately after coating or stored under high vacuum.
Tantalum is an oxidising metal and – as with chromium - requires a high vacuum sputter coater fitted with an automatic source shutter. The Safematic CCU-010 HV high vacuum sputter coater is recommended.