Thermal Management of Low-Temperature Semiconductor Detector Devices

The next generation of physics experiments using highly sensitive skipper-CCD detectors, including low mass dark energy, will require large arrays of these detectors operating at cryogenic temperatures. The currently planned cooling system involves submerging these sensors in pressurized liquid nitrogen. This presents significant engineering challenges, especially considering the strict requirements for ultra-low background radiation and the associated shielding required. We are developing an alternative cryogenic cooling technology for the thermal management of semiconductor detector arrays, such as the Skipper-CCDs, used in high energy physics experiments such as low mass dark energy searches. The proposed thermal management system involves the use of a novel cryogenic loop heat pipe to extract, transfer, and reject waste heat from the sensor array. the Phase I program, the feasibility of the proposed cryogenic loop heat pipe cooling system was demonstrated through sub-scale prototype design, analysis, fabrication, and testing. The sub-scale prototype testing demonstrated the capability to uniformly cool a large-area heat source such as a detector array. A detailed trade study of the cryogenic loop heat pipe materials and working fluids for low-background radiation was performed, and a material selection was made for further development in Phase II. Finally, a preliminary full-scale system design for a dark mass search experiment was developed. In the Phase II program, the cryogenic loop heat pipe technology for cooling of large-area detector arrays will be further developed and matured. The feasibility of the low-background material selection will be demonstrated through sub-scale prototype testing. Finally, a full-scale prototype design of a thermal management system for the target dark matter experiment will be developed and tested. If successful, the technology developed Phase II program will provide the physics community with an alternative low radiation background cryogenic cooling solution for semiconductor detectors proposed for use in many upcoming experiments. The proposed system is also easily adaptable to cooling of large array detector arrays on space-based experiments. The proposed loop heat pipe based cryogenic cooling technology provides a versatile and adaptable solution for thermal management of physics experiments, both on the ground and in space, helping to increase the pace of scientific discovery. Other applications include additional spacecraft thermal management applications and the cooling of zero boil-off cryogen storage tanks.