Modular assembly/packaging of multi-substrate microsystems (WIMS Cube) using thermo-magnetically actuated cables

The authors report a packaging/assembly approach for wireless integrated microsystems (WIMS) using flexible thermo-magnetically actuated cables. In this assembly approach, substrates of a microsystem are stacked on top of one another inside a cube (WIMS cube). Electrical/fluidic signals are transferred between system dice using rows of integrated flexible parylene cables attached to cube walls, and actuated, row-by-row during assembly, to make pressure contacts to each die. Actuation of these cables is achieved using thermo-magnetic actuation; resistively generated heat softens up the parylene cable, and magnetic actuation plastically deforms the soft cable. Cubes with integrated parylene cables have been fabricated. Thermo-magnetically actuated 1mm × 1.3mm cables have been shown to deflect ∼800μm with two stable positions in a 0.1T magnetic field at a ∼90°C temperature achieved by resistive heating.