Giant Magneto-Resistive Effect based Sensor on Laser Direct Structured MID Substrates

This paper covers the successful manufacturing of Giant Magneto-Resistive (GMR) spin valve sensors consisting of a highly precise thin film stack of partially only three nanometer thin metal layers on the high-performant polymer polyether-ether-ketone (PEEK). By means of injection molding, disk-shaped wafer-like substrates were made including meandering cavities for subsequent sputter deposition. After a polishing step, a backside contact was established using the technique of laser direct structuring. The entire production process replaces and simplifies the classical lithography and masking processes almost rendering a clean room redundant. Sensors manufactured this way on PEEK substrate show a magneto-resistive effect of 3.7 % in comparison to 7.2 % for sensors gained with the same deposition parameters on silicon dioxide.