The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 27, 1989
Filed:
Mar. 14, 1988
Thomas Bayer, Sindelfingen, DE;
Michael Elsasser, Herrenberg, DE;
Johann Greschner, Pliezhausen, DE;
Heinrich Schmid, Tiefenbronn, DE;
Roland Stohr, Nufringen, DE;
Olaf Wolter, Schonaich, DE;
Jurgen Wittlinger, Boblingen, DE;
International Business Machines Corporation, Armonk, NY (US);
Abstract
The contact probe arrangement includes a stack of perforated plates (1, 1a) through which extend a plurality contact probes. The stack of perforated plates consists of two kinds of plates. The first kind forms the lowermost plates (1a). They have circular or square holes permitting a vertical placing of the contact probes onto the contact pads (4) of the device (5) to be tested. The plates (1) of the second kind have oblong, rectangular, square, circular, elliptical or trapezoidal holes (3). With respect to the stacked plates of the second kind, alternate ones are offset against the two other adjacent plates which are aligned relative to each other, in such a manner that each contact probe is surrounded by part of the lower edge of the upper of two adjacent perforated plates, and part of the upper edge of the lower of two adjacent perforated plates. If axial stress is applied, the contact probe can thus not buckle any farther than to a part of the perforation wall limiting its maximum buckling. This ensures a sufficiently low contact resistance between the contact probe and the contact pad of the device to be tested. By using a corresponding number of perforated plates of the second kind the contact probes can adapt to height differences of the contact pads caused by irregularities in the surface of the device to be tested.