High density integrated circuit apparatus, test probe and methods of use thereof

Abstract

The present invention is directed to a high density test probe which provides a means for testing a high density and high performance integrated circuits in wafer forms or as discrete chips. The test probe is formed from a dense array of elongated electrical conductors which are embedded in an compliant or high modulus elastomeric material. A standard packaging substrate, such as a ceramic integrated circuit chip packaging substrate is used to provide a space transformer. Wires are bonded to an array of contact pads on the surface of the space transformer. The space transformer formed from a multilayer integrated circuit chip packaging substrate. The wires are as dense as the contact location array. A mold is disposed surrounding the array of outwardly projecting wires. A liquid elastomer is disposed in the mold to fill the spaces between the wires. The elastomer is cured and the mold is removed, leaving an array of wires disposed in the elastomer and in electrical contact with the space transformer. The space transformer can have an array of pins which are on the opposite surface of the space transformer opposite to that on which the elongated conductors are bonded. The pins are inserted into a socket on a second space transformer, such as a printed circuit board to form a probe assembly. Alternatively, an interposer electrical connector can be disposed between the first and second space transformer.

Description

FIELD OF THE INVENTION [0001] This invention related to an apparatus and test probe for integrated circuit devices and methods of use thereof. BACKGROUND OF THE INVENTION [0002] In the microelectronics industry, before integrated circuit (IC) chips are packaged in an electronic component, such as a computer, they are tested. Testing is essential to determine whether the integrated circuit's electrical characteristics conform to the specifications to which they were designed to ensure that electronic component performs the function for which it was designed. [0003] Testing is an expensive part of the fabrication process of contemporary computing systems. The functionality of ever I / O for contemporary integrated circuit must be tested since a failure to achieve the design specification at a single I / O can render an integrated circuit unusable for a specific application. The testing is commonly done both at room temperature and at elevated temperatures to test functionality and at elev...

AI Technical Summary

Benefits of technology

The present invention provides an improved high density test probe, test apparatus, and method of use. The test probe has contacts designed for high performance functional testing and high temperature burn-in applications. The probes can be reworked several times by resurfacing some of the materials used to fabricate them. The test probe has a probe tip member containing a plurality of elongated conductors each ball bonded to electrical contact locations on a workpiece to be tested. The elongated conductors are embedded in a material and electrically connected to contact locations on a fan-out substrate or a socket on a second fan-out substrate. The test probe is part of a test apparatus and test tool. The method of fabricating the probe tip involves bonding a plurality of elongated conductors to contact locations on a substrate surface and projecting them away from the substrate. The elongated conductors can be embedded in an elastomeric material to form a probe tip for the structure. The technical effects of the present invention include improved testing accuracy and reliability, reduced testing time and cost, and improved probe design flexibility.

Problems solved by technology

Testing is an expensive part of the fabrication process of contemporary computing systems.

The functionality of ever I / O for contemporary integrated circuit must be tested since a failure to achieve the design specification at a single I / O can render an integrated circuit unusable for a specific application.

Contemporary probes for integrated circuits are expensive to fabricate and are easily damaged.

The wires are generally fragile and easily damage and are easily displaceable from the predetermined positions corresponding to the design positions of the contact locations on the integrated circuit being tested.

These probes last only a certain number of testing operations, after which they must be replaced by an expensive replacement or reworked to recondition the probes.

Structure 2 of FIG. 1 has the disadvantage of being expensive to fabricate and of having fragile inner ends 20 of electrical conductors 16.

Ends 20 are easily damaged through use in probing electronic devices.

Since the probe 2 is expensive to fabricate, replacement adds a substantial cost to the testing of integrated circuit devices.

Tungsten has an undesirably high resistivity.

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