Electroplating Ni micro-cantilevers for low contact-force IC probing

We present a new MEMS probe card made of electroplated nickel micro-cantilevers, which has compliant structures, and uses a kind of electric breakdown, or fritting, to make electric contacts to electrodes on ICs. The characteristics of fritting contact between nickel probe and Al electrodes were investigated, and nickel was found to have lower contact resistance than other materials. A micro-machining process for the probe cards, including deposition of layers having different internal stress to make a protruding cantilever shape, was developed. It was found that the fritting process using the micro-cantilevers could make the low-resistance contacts with the force of less than a few micronewtons.