Micromachining Techniques to Enhance X-ray Microcalorimeter Array Fabrication

ProcessTek describes an innovative large format cryogenic x-ray detector consisting of an array of magnetic microcalorimeters with SQUID readouts. Pixels consist of a thick-film x-ray absorber deposited on a paramagnetic alloy that is coupled to a dc SQUID. A research collaboration headed by Prof. Seidel at Brown University, including participants from the University of Heidelberg, Smithsonian Astrophysical Observatory, Star Cryoelectronics and Hypres, have conducted a research program investigating the relevant properties of appropriate magnetic systems. They have achieved impressive results with individual pixel,microcalorimeter designs. Next, they will develop new microprocessing techniques and multiplexed SQUID electronics systems. Their Focal Plane Array design has significant fabrication problems to overcome to process a high performance and manufacturable array. The purpose of this proposed SBIR research plan is complementary to this effort. We propose to develop some specific practical processing details based on MEMS and micromachining techniques that will enable us to transform this high potential microcalorimeter concept, to a marketable product that could be sold to a potentially large market. We will work closely with Professor Seidel's collaboration, sharing ideas and investigation results, and members of this collaboration will test all new devices developed by ProcessTek at the appropriate cryogenic temperatures.