Probe cards employing probes having retaining portions for potting in a retention arrangement
View Patent ↗Method and apparatus using a retention arrangement with a potting enclosure for holding a plurality of probes by their retention portions, the probes being of the type having contacting tips for establishing electrical contact with pads or bumps of a device under test (DUT) to perform an electrical test. The retention arrangement has a top plate with top openings for the probes, a bottom plate with bottom openings for the probes, the plates being preferably made of ceramic with laser-machined openings, and a potting enclosure between the plates for admitting a potting agent that upon curing pots the retaining portions of the probes. In some embodiments a spacer is positioned between the top and bottom plates for defining the potting enclosure. Alternatively, the retention arrangement has intermediate plates located in the potting enclosure and having probe guiding openings to guide the probes.
1. An apparatus for electrical testing, comprising:
a) a plurality of probes, each of said probes having:
I. a connect end for applying a test signal;
II. a retaining portion;
III. at least one arm portion; and
IV. a contacting tip for making an electrical contact with a device under test;
b) a retention arrangement for holding each of said probes by said retaining portion, said retention arrangement having:
I. a top plate having top openings for said probes;
II. a bottom plate having bottom openings for said probes; and
III. a potting enclosure between said top plate and said bottom plate for potting said retaining portion in a potting agent.
2. The apparatus of claim 1 , wherein said retention arrangement further comprises intermediate plates located in said potting enclosure and having probe guiding openings for said probes, said intermediate plates having sufficient inter-plate spacing to admit said potting agent therebetween.
3. The apparatus of claim 1 , further comprising a spacer positioned between said top plate and said bottom plate for delimiting said potting enclosure.
4. The apparatus of claim 1 , wherein said top openings and said bottom openings are laser-machined openings.
5. The apparatus of claim 1 , wherein said retention arrangement further comprises an admission opening for receiving said potting agent.
6. The apparatus of claim 5 , wherein said potting agent comprises an epoxy.
7. The apparatus of claim 1 , further comprising a space transformer having contacts for contacting said probes at said connect end.
8. The apparatus of claim 1 , wherein said probes each comprise at least two arm portions.
9. The apparatus of claim 8 , wherein said at least two arm portions comprise a base arm portion extending away from a center axis of said probe, a reverse arm portion extending toward said center axis, and said probe further comprises a knee joining said base arm portion with said reverse arm portion.
10. The apparatus of claim 9 , wherein said contacting tip is located on said reverse arm portion distal said knee and said contacting tip has a non-zero offset relative to said center axis.
11. The apparatus of claim 10 , wherein said contacting tip further comprises a scrubbing protrusion.
12. The apparatus of claim 1 , wherein said at least one arm portion comprises a non-linear arm portion.
13. The apparatus of claim 12 , wherein said non-linear arm portion extends away from a center axis of said probe such that said contacting tip has a non-zero offset relative to said center axis.
14. The apparatus of claim 1 , wherein said contacting tip has a protrusion for making said electrical contact.
15. The apparatus of claim 1 , employed in a probe card.