The National Institute of Standards and Technology (NIST) is seeking responses to a Sources Sought Notice for the fabrication of custom magneto-resistive sensors. These sensors are intended for use in a scanning magnetic microscope being developed for the CHIPS Metrology Project, specifically for acquiring 3D thermal images in semiconductor packages. The procurement requires sensors that meet specific technical specifications, including a frequency range from DC to 100 kHz, field sensitivity parameters, and operational conditions, with a minimum delivery of 100 sensors. Interested parties should respond to the primary contact, Cielo Ibarra, at cielo.ibarra@nist.gov, with their capabilities and relevant experience by the deadline of December 12, 2025, for any questions regarding the notice.