Cryogenic thermal storage system for discontinuous industrial vacuum processes

Phase Change Materials are proposed for refrigerating systems in discontinuous industrial vacuum processes where temperatures as low as 140 ÷ 100°C are necessary within time-frames representing 10÷20% of total operating time. An application is proposed for cooling systems used in a Physical Vapour Deposition (PVD) apparatus. A prototype has been manufactured which couples a cryopump with a reservoir filled with MethylCycloPentane (MCP-C6H12) and a distribution line where nitrogen in the gaseous state is flowing. Preliminary tests show that temperatures of about 120°C are actually achieved within time windows compatible with PVD applications.