A post-fabrication selective magnetic annealing technique in standard MEMS processes

A selective electrothermalmagnetic annealing technique is introduced that provides programming capabilities for mechanical micro-resonators. In the proposed approach, the magneticproperties ofresonators can be locally tuned in a post-fabrication batch-compatible process step. A prototype is implemented in a standard microfabrication process, where resonatingferromagnetic elements are suspended on top of a polysilicon resistiveheater. Theferromagnetic elements consist of electroplated Nickel (Ni) with minor Iron (Fe) impurities. The electro-thermo-mechanical heating phenomenon is simulated for design purposes. Themagnetization of micro-resonators with and withoutmagnetic annealing ismeasured. The resulting magneticproperty enhancement is illustrated by hysteresis (M-H) loop variations.

Source: Applied Physics Letters - December 1, 2016 Category: Physics Authors: A. Mohammadi, N. C. Karmakar and M. R. Yuce Source Type: research