Plated probe structure
View Patent ↗A plated test probe structure for testing electrical connections to integrated circuits (IC) devices with solder bumped interconnection pads that are an integral part of the fan-out wiring on the test substrate, or other printed wiring device.
1. A plated test probe for making electrical contact with a plurality of solder ball connections on an integrated circuit device comprising:
a first fan-out substrate having a first surface;
wherein said ran out substrate comprises:
multilayer ceramic substrates with thick film wiring;
multilayer ceramic substrates with thin film wiring;
metallized ceramic substrates with thin film wiring;
epoxy glass laminate substrates with copper wiring; or
silicon substrates with thin film wiring:
said first surface having a plurality of contact locations;
a plurality of plated bumps attached to said plurality of contact locations;
said plated probe comprising a multilayer structure having:
a first adhesion layer formed from a material selected from the group consisting of Cr, Ti, Ta, Hf, Mo, W, Nb, V, Zr, and alloys thereof;
a second layer comprising the predominate constituent of a metal bump formed from a material selected from the group consisting of Cu, Pd, Au, Ni, Co, Fe and alloys thereof,
a third contact metallurgy layer formed from a material selected from the group consisting of Re, Rh, Ru, Pd, Pt, Au, and alloys thereof.
2. The plated test probe according to claim 1 , which further includes a raised cross feature located on the top surface of said plated probe.
3. The probe structure according to claim 1 , which further includes a raised pointed contact feature on top of the flat metal bump surface.
4. The plated probe structure according to claim 1 wherein a diffusion barrier layer is inserted underneath said contact metallurgy layer.
5. The plated probe structure according to claim 4 wherein said the diffusion barrier layer is formed from a material selected from the group consisting of Cr, Ti, Ta, Zr, Ni, Fc, and alloys thereof.
6. The plated test probe according to claim 1 wherein said plated metal bump possesses a top surface having a concave geometry feature on said top surface of said plated bump.
7. The plated lest probe according to claim 6 , wherein said concave geometry feature on the top surface of said plated bumps further includes a raised pointed contact feature located in the center of said plated bump.