Large-Area Superconducting Tape Processing Using Novel Inverted Cylindrical Magnetron PVD/Etch/e-CVD Technique

This SBIR project addresses the need for scalable manufacturing techniques for high-quality coatings on Gen2.5 rare-earth barium copper oxide (REBCO) high-temperature superconducting (HTS) tapes needed for high-beta magnetic containment nuclear fusion concepts. Volumetric fusion power density is proportional to B4, so a doubling in current leads to a factor of 16× reduction in size/economics or increase in energy output. With demonstrable peak currents approaching >1kA/mm2 and strength to sustain high B-field force, the demand for HTS tape has exploded; however, costs remain high.The SBIR technical approach is targeting two pain points related to PVD deposition of the Ag stabilizer/contact layer (costly $$$, low target utilization, high thickness) and replacing Cu electroplating around the tape assembly with an all PVD quasi-conformal approach. These pain points are coupled because due to the reactive nature of the Cu electroplating bath, the Ag stabilizer layer must be sufficiently thick enough to resist penetration, corrosion and oxygen-depletion of the underlying REBCO active layer. Consequently, several microns of Ag are typically used whereas only 100nm would suffice leading to additional cost ($/kA-m) and overall tape thickness (magnet peak B-field achievable).The opportunity presents to leverage a technology developed for precision coatings for accident tolerant nuclear fuel claddings as a solution for these pain points that is scalable for high-volume manufacturing. This SBIR seeks to validate the technical approach with university involvement.A successful SBIR/STTR will target critical pain points and barriers to help lower the cost and increase manufacturing capacity for Gen2.5-HTS tape for high-strength superconducting magnets. The anticipated public benefit is greater access to electricity and distribution, plus modest improvements in medical diagnostic imaging (MRI) from the availability of intense superconducting magnetic technology. Lastly, we can bury the adage that “fusion is always 30 years away” and increase domestic manufacturing.