Cryogenic Bolometer Array Technology development on 150 mm wafers

The number of polarization sensitive detectors need for field deployed Cosmic Microwave Background (CMB) experiments has been growing steadily from 1000 of stage-II to 10,000 stage-III and projected detectors of over 100,000 for CMB-S4 experiments. P5 recommendation: "The Particle Physics Project Prioritization Panel (P5) outlined a strategic plan for US particle physics research over the coming decade in 2014. The panel recommended, "support CMB experiments as part of the core particle physics program. The multidisciplinary nature of the science warrants continued multiagency support." In response to the recommendation, CMB community started planning CMB Stage IV (CMB-S4), which aims to make definitive measurement of the early universe with ~100,000 detectors." Such a task will involve the fabrication of over 1000 successful wafers within a relatively short period. HYPRES in collaboration with LBNL will develop Cosmic Microwave Background (CMB) superconducting detector array fabrication process on HYPRES’s 150-mm (6-inch) superconducting electronics fabrication facility. HYPRES is the only commercial superconductor electronics company in the us equipped with 150 mm wafer processing equipment. This process will be scalable for a higher volume, lower cost, high yield production to meet the requirements of the stage-IV. It has increasingly been clear that the next phase of development of detectors for CMB experiments will require well maintained with controlled environments micro-fabrication facilities. HYPRES’ fabrication facility fits this requirement very well; added to that, the decades of experience with low temperature superconducting electronics fabrication processes gives HYPRES an edge to deliver wafers needed for the CMB experiments. The primary goal of this program is the development of cryogenic bolometer array technology for future Cosmic Microwave Background experiments. In doing so the project will focus on merging the niobium processes and MEMS processes on a 150 mm wafers. The experience and know how gained during the development effort will accelerate the fabrication development effort of many other applications within the Hypres product line that require these two fabrication processes. A streamlined and optimized MEMS processes will lead to a significant improvement in the performance and cost of fabrication processes. Some of the current and future application that would benefit from this include: transition edge sensor bolometers, RF-MEMS, tunable amplifiers, capacitive sensors, sensitive thermopile, through-vias for 3D chip integration of quantum computing circuits (QUBITS) to classical control circuits (HYPRES’ ERSFQ logic).