International Business Machines Corporation

Jurgen Wittlinger

Johann Greschner

Thomas Bayer

Johann W Bartha

Olaf Wolter

Roland R Stohr

Michael Elsasser

Heinrich Schmid

According to a preferred embodiment, arbitrarily shaped holes are fabricated in 0.1 to 2 mm thick plates of polyoxymethylene homo- or copolymers. For that purpose, the polymeric substrate is photoresist-coated on either side; the desired pattern is simultaneously applied to both the front and the back side of the photoresist layers by imagewise exposure at optimum mask alignment; the photoresist layers are developed and blanket-exposed; the resultant photoresist structures are treated with a cyclic organosilicon compound and postbaked; the through holes are produced by sequential reactive ion etching of the polyoxymethylene from the front and the back side, each time down to a depth of about 2/3 of the substrate thickness; and the silylated photoresist masks are stripped from the front and the back side of the substrate.

Process for fabricating arbitrarily shaped through holes in a component

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.

Contact probe arrangement for electrically connecting a test system to

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Boblingen, Germany

Jurgen Wittlinger