Formfactor, Inc.

Mukesh K Selvaraj

January Kister

Li Fan

Darcy K Kelly-Greene

Gensaku Nagai

Jim Zhang

Edward J Milovic

A probe-on-carrier architecture is provided, where several vertical probes are disposed on each probe carrier and the probe carriers are affixed to the space transformer. Each vertical probe has two flexible members. The first flexible member makes electrical contact to the space transformer. The second flexible member makes temporary electrical contact to the device under test. A mechanical stiffener can be used to deal with the possible lack of flatness and thermal expansion of the space transformer. The mechanical stiffener can be affixed to the space transformer to bring the flatness and thermal expansion of the space transformer to within specifications. Alternatively, the mechanical stiffener can be affixed to the space transformer without trying to bring the flatness and thermal expansion of the space transformer to within specifications.

Probe on carrier architecture for vertical probe arrays

Probes are connected to the space transformer via multiple carrier plates. Electrical contacts from the probes to the space transformer are by way of spring tail features on the probes that connect to the space transformer and not to the carrier plates. In other words, the carrier plates are purely mechanical in function. This configuration can significantly reduce probe array fabrication time relative to sequential placement of individual probes on the space transformer. Multiple probe carrier plates can be populated with probes in parallel, and the final sequential assembly of carrier plates onto the space transformer has a greatly reduced operation count. Deviations of the space transformer from flatness can be compensated for.

MEMS probe card assembly having decoupled electrical and mechanical probe connections

A probe card assembly can comprise a guide plate comprising probe guides for holding probes in predetermined positions. The probe card assembly can also comprise a wiring structure attached to the guide plate so that connection tips of the probes are positioned against and attached to contacts on the wiring structure. The attachment of the guide plate to the wiring structure can allow the wiring structure to expand or contract at a greater rate than the guide plate. The probes can include compliant elements that fail upon high electrical current and thermal stresses located away from the contact tips.

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Livermore, CA, United States of America

Mukesh K Selvaraj