Low profile probe having improved mechanical scrub and reduced contact inductance
View Patent ↗A vertically folded probe is provided that can provide improved scrub performance in cases where the probe height is limited. More specifically, such a probe includes a base and a tip, and an arm extending from the base to the tip as a single continuous member. The probe arm is vertically folded, such that it includes three or more vertical arm portions. The vertical arm portions have substantial vertical overlap, and are laterally displaced from each other. When such a probe is vertically brought down onto a device under test, the probe deforms. During probe deformation, at least two of the vertical arm portions come into contact with each other. Such contact between the arm portions can advantageously increase the lateral scrub motion at the probe tip, and can also advantageously reduce the probe inductance.
1. A probe array for testing a device under test comprising:
a plurality of probes, wherein each of said plurality of probes comprises:
a base;
a tip;
an arm extending from said base to said tip, said arm comprising a plurality of vertical portions and a lateral termination; and
at least one of said vertical portions having a substantial vertical overlap with another said vertical portion of an adjacent probe.
2. The probe array of claim 1 wherein said vertical portions are substantially parallel to a scrub direction.
3. The probe array of claim 2 wherein said scrub direction comprises a lateral scrub direction.
4. The probe array of claim 1 wherein said vertical portions are laterally displaced from each other.
5. The probe array of claim 1 wherein said tip is disposed on said lateral termination.
6. The probe array of claim 1 wherein said tip comprises a reduced-width protrusion for making electrical contact.
7. The probe array of claim 1 wherein at least one of said probes comprises three of said vertical portions.
8. The probe array of claim 1 wherein said arm comprises a single continuous member.
9. The probe array of claim 1 wherein said vertical portions provide a current path having a reduced inductance from said base to said tip.
10. The probe array of claim 1 further comprising a clamping plate for mounting said plurality of probes.
11. The probe array of claim 1 further comprising a fixture for mounting said plurality of probes.
12. The probe array of claim 1 wherein at least one of said probes is disposed on a metalized pad.
13. The probe array of claim 12 wherein said metalized pad is disposed on a carrier.
14. The probe array of claim 13 further comprising a via that passes through said carrier and connects a first contact pad to a second contact pad.
15. The probe array of claim 14 further comprising a space transformer disposed on said carrier.
16. The probe array of claim 15 wherein said space transformer comprises solder bumps for connecting to said carrier.
17. The probe array of claim 1 wherein said probes are arranged orthogonally.
18. The probe array of claim 1 wherein said probes are arranged diagonally.
19. The probe array of claim 1 wherein said vertical portions are not disposed in a common plane.
20. The probe array of claim 1 wherein said vertical portions are disposed in a common plane.
21. The probe array of claim 1 wherein at least two of said vertical portions contact each other as contact is made between at least one of said probes and the device under test.