Probe card assembly and kit
AssigneeFormFactor, Inc.
InventorsIgor Y. Khandros, A. Nicholas Sporck, Benjamin N. Eldridge
Life of this patent
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AssigneeFormFactor, Inc.
InventorsIgor Y. Khandros, A. Nicholas Sporck, Benjamin N. Eldridge
Estimating the term…
In a probe card assembly, a series of probe elements can be arrayed on a silicon space transformer. The silicon space transformer can be fabricated with an array of primary contacts in a very tight pitch, comparable to the pitch of a semiconductor device. One preferred primary contact is a resilient spring contact. Conductive elements in the space transformer are routed to second contacts at a more relaxed pitch. In one preferred embodiment, the second contacts are suitable for directly attaching a ribbon cable, which in turn can be connected to provide selective connection to each primary contact. The silicon space transformer is mounted in a fixture that provides for resilient connection to a wafer or device to be tested. This fixture can be adjusted to planarize the primary contacts with the plane of a support probe card board.
A method of making a probe card assembly for probing a semiconductor wafer, the method comprising:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Surface contacts, e.g. bumps: using auxiliary conductive elements, e.g. pieces of metal foil, metallic spheres
Specially adapted for particular articles or work: soldering of electronic components
Specially adapted for particular articles or work: wire welding
With individual probe elements, e.g. needles, cantilever beams or bump contacts, fixed in relation to each other, e.g. bed of nails fixture or…:…
Term ended 16 Nov 2013 (estimated)
The invention relates to an apparatus and associated techniques for making pressure connections between electronic components with resilient (spring) contact elements, such as for performing test and burn-in procedures on semiconductor devices prior to their packaging, preferably prior to the individual semiconductor devices being singulated from a semiconductor wafer.
The aforementioned commonly-owned, copending U.S. patent application Ser. No. 08/554,902 filed 9 Nov. 1995 and its corresponding PCT Patent Application No. PCT/US95/14844 filed 13 Nov. 1995 (WO96/15458, published 23 May 1996), both by ELDRIDGE, GRUBE, KHANDROS and MATHIEU, disclose a probe card assembly. As illustrated, for example, in FIG. 5 therein, the probe card assembly (500) includes a probe card (502), a space transformer (506) having resilient contact structures (probe elements 524) mounted directly to and extending from terminals (522) on a surface thereof, and an interposer (504) disposed between the space transformer (506) and the probe card (502). The space transformer (506) and interposer (504) are “stacked up” so that the orientation of the space transformer (506), hence the orientation of the tips of the probe elements (524), can be adjusted without changing the orientation of the probe card. Suitable mechanisms (532, 536, 538, 546) for adjusting the orientation of the space transformer (506), and for determining what adjustments to make, are disclosed therein. Multiple die sites on a semiconductor wafer (508) are readily probed using the disclosed techniques, and the probe elements (524) can be arranged to optimize probing of an entire wafer (508). As shown, for example, in FIG. 2A therein, the resilient contact structures or probe elements (524) are suitably (but not limited to) composite interconnections elements (200) having a relatively soft core (206) overcoated by a relatively hard shell (218,220).
Generally, the present invention obviates the need for using a space transformer (e.g., 506) and an interposer (504) in a probe card assembly that may be adjusted in a manner similar to that described in the above-referenced patent applications.
Reference will be made in detail to preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. The drawings are intended to be illustrative, not limiting. Although the invention will be described in the context of these preferred embodiments, it should be understood that it is not intended to limit the spirit and scope of the invention to these particular embodiments.
Certain elements in selected ones of the drawings are illustrated not-to-scale, for illustrative clarity. Often, similar elements throughout the drawings are referred to by similar reference numerals For example, the element 199 may be similar in many respects to the element 299 in another figure. Also, often, similar elements are referred to with similar numbers in a single drawing. For example, a plurality of elements 199 may be referred to as 199a, 199b, 199c, etc.
FIG. 1 is an exploded view, partially in cross-section, of a probe card assembly such as is disclosed in the aforementioned U.S. patent application Ser. No. 08/554,902 and its counterpart PCT/US95/14844, and illustrates certain techniques which are relevant to the present invention.
This patent application is directed to probe card assemblies, components thereof, and methods of using same. As will be evident from the description that follows, the use of resilient (spring) contact structures to effect pressure connections to terminals of an electronic component is essential. The resilient contact structures are suitably (but not necessarily) implemented as “composite interconnection elements”, such as have been described in the disclosure of the aforementioned U.S. patent application Ser. No. 08/452,255 (“PARENT CASE”), incorporated by reference herein.
According to an aspect of the invention, the probe elements (resilient contact structures extending from the top surface of the space transformer component) are preferably formed as “composite interconnection elements” which are fabricated directly upon the terminals of the space transformer component of the probe card assembly. The “composite” (multilayer) interconnection element is fabricated by mounting an elongate element (“core”) to an electronic component, shaping the core to have a spring shape, and overcoating the core to enhance the physical (e.g., spring) characteristics of the resulting composite interconnection element and/or to securely anchor the resulting composite interconnection element to the electronic component. The resilient contact structures of the interposer component may also be formed as composite interconnection elements.
The use of the term “composite”, throughout the description set forth herein, is consistent with a ‘generic’ meaning of the term (e.g., formed of two or more elements), and is not to be confused with any usage of the term “composite” in other fields of endeavor, for example, as it may be applied to materials such as glass, carbon or other fibers supported in a matrix of resin or the like.