Probe-on-substrate

摘要

Probes are directly patterned on a test substrate, thereby eliminating a need for an interposer. Probe contact structures are formed as a two-level structure having a greater lateral dimension for a lower level portion than for an upper level portion. First cavities are formed in a masking layer applied to a test substrate, filling the cavities with a conductive material, and planarizing the top surfaces of the conductive material portions to form lower level portions. Another masking layer is applied over the lower level portions and patterned to define second cavities having a smaller lateral dimension that the lower level portions. The second cavities are filled with at least one conductive material to form upper level portions of the probe contact structures. The upper level portion of each probe contact structure can be employed to penetrate a surface oxide of solder balls.

主权项

1. A method of forming a probing apparatus, said method comprising:
applying a first masking layer over a substrate; patterning said first masking layer to form a plurality of first cavities extending to a top surface of said substrate; depositing a first conductive material in said plurality of first cavities; planarizing said patterned first masking layer and said deposited first conductive material to form a plurality of first columnar conductive structures embedded in said patterned first masking layer; applying a second masking layer over said patterned first masking layer; patterning said second masking layer to form a plurality of second cavities extending to top surfaces of said plurality of first columnar conductive structures; and depositing a second conductive material in said plurality of second cavities to form a plurality of second columnar conductive structures, wherein a probing apparatus comprising a plurality of conductive probes located on said substrate is formed, and said plurality of conductive probes comprises said plurality of first columnar conductive structures and said plurality of second columnar conductive structures.