Electrical and Mechanical Assembly of High-Density Three-Dimensional Micro-Fabricated Arrays

In exemplary implementations of this invention, electrical connections are fabricated between two orthogonal surfaces by electroplating. The two surfaces are separated (except for the electrical connections) by a gap of not more than 100 micrometers. Multiple electrical connections may be fabricated across the gap. In preparatory steps, conductive pads on the two surfaces may be separately electroplated to build up “bumps” that make it easier to bridge the remainder of the gap in a final plating step. Alternately, electroless deposition may be used instead of electroplating. In exemplary implementations, a 3D probe array may be assembled by inserting array structures into an orthogonal base plate. The array structures may be aligned and held in place, relative to the base plate, by mechanical means, including side hooks, stabilizers, bottom hooks, alignment parts and a back plate.