Electricity: measuring and testing – Fault detecting in electric circuits and of electric components – Of individual circuit component or element
Reexamination Certificate
1998-10-05
2001-08-28
Karlsen, Ernest (Department: 2858)
Electricity: measuring and testing
Fault detecting in electric circuits and of electric components
Of individual circuit component or element
Reexamination Certificate
active
06281692
ABSTRACT:
BACKGROUND OF THE INVENTION
The present invention relates to an interposer for electrically testing a ceramic substrate, and more particularly, relates to an interposer used to maintain temporary contact between a ceramic substrate and a test bed comprising so-called pogo pin contactors.
A ceramic substrate is used in the electronics industry for carrying at least one semiconductor device. Usually there are mounted a plurality of semiconductor devices on the ceramic substrate. A ceramic substrate usually consists of a plurality of insulative layers containing wiring patterns and vias which connect between the layers. In totality, the wiring patterns and vias form wiring nets and, in use, provide electrical contact between the various semiconductor devices and between the various semiconductor devices and the next level of packaging.
Before mounting the semiconductor devices, it is necessary to ensure that all the wiring nets are insulated from each other and have the proper electrical continuity.
Accordingly, it is necessary to have a temporary method of connecting the ceramic substrate with a test bed, which for the purposes of the present invention contains a plurality of pogo pin contactors. The ceramic substrate contains input/output devices which connect to the next level of packaging but are also used for testing the wiring nets of the ceramic substrate. The input/output devices may be, for example, pads, pins or solder balls. In the test bed, the pogo pin contactors have a single spring loaded tip which eventually must make electrical contact with the input/output devices of the ceramic substrate. Pogo pins may have single or double spring loaded tips.
Pogo pins and pogo pin contactors are generic for the class of telescoping, spring-loaded connecting pins. Pogo pins and pogo pin contactors are commercially available from companies such as Interconnect Devices, Inc., Kansas City, Kans. Whenever pogo pins and pogo pin contactors are used throughout this application, it should be understood that telescoping, spring-loaded connecting pins are intended.
Too, the input/output devices of the ceramic substrate may have a different grid than the test bed pogo pin contactors so it is necessary to have a grid transformer to accommodate the various differences in grids.
Various devices have been proposed for making nonpermanent connections between electronic devices.
Kato et al. U.S. Pat. No. 5,727,954, the disclosure of which is incorporated by reference herein, discloses an interposer for making connection between an integrated circuit device and a substrate. The interposer includes spring-loaded contact pins for making the connection.
Sayre et al. U.S. Pat. No. 5,773,988, the disclosure of which is incorporated by reference herein, discloses a hybrid test fixture in which various spring loaded probes, guide plates and wires are utilized to make connection between a test board and a printed circuit board.
Antonello et al. U.S. Pat. No. 5,767,692, the disclosure of which is incorporated by reference herein, discloses a test fixture consisting of plates and long needles for converting between the test grid and the grid of the printed circuit board under test.
Kimura et al. U.S. Pat. No. 5,574,382, the disclosure of which is incorporated by reference herein, discloses an interposer consisting of spring loaded needles for testing a printed circuit board. Also disclosed is a pitch-converting board for converting between the pitch of the printed circuit board contacts under test and the contacts of the test board.
In view of the above, it is a purpose of the present invention to have an interposer for temporarily connecting a ceramic substrate to a test bed for electrical testing.
It is another purpose of the present invention to have an interposer for temporarily connecting a ceramic substrate to a test bed for electrical testing and which will also accommodate a different grid between the ceramic substrate and the test bed.
BRIEF SUMMARY OF THE INVENTION
A first aspect of the invention relates to an interposer for maintaining temporary contact between a substrate and a pogo pin contactor comprising:
a nonconductive body having first and second surfaces and having at least one cavity within the nonconductive body, the at least one cavity comprising a central portion and first and second passageways connecting between the central portion and the first and second surfaces, respectively, of the nonconductive body, wherein one of the first and second passageways is adapted to receive a pogo pin contactor and the other of the first and second passageways is adapted to facilitate contact with a substrate; and
a rigid, electrically conductive element freely moveable within the central portion of the nonconductive body for making contact with and between the pogo pin and a contact element of the substrate through the first and second passageways.
A second aspect of the invention relates to a test structure for testing at least one electrical property of a substrate comprising:
a test bed having at least one pogo pin contactor; and
an interposer for maintaining temporary contact between a substrate and the pogo pin contactor, the interposer comprising:
a nonconductive body having first and second surfaces and having at least one cavity within the nonconductive body, the at least one cavity comprising a central portion and first and second passageways connecting between the central portion and the first and second surfaces, respectively, of the nonconductive body, wherein one of the first and second passageways is adapted to receive the pogo pin contactor and the other of the first and second passageways is adapted to facilitate contact with a substrate; and
a rigid, electrically conductive element freely moveable within the central portion of the nonconductive body for making contact with and between the pogo pin and a contact element of the substrate.
A third aspect of the invention relates to an interposer and grid transformer for maintaining temporary contact between a substrate and a plurality of pogo pin contactors comprising:
a nonconductive body having first and second adjoining layers;
the first layer containing a plurality of pogo pins set in a first grid for contacting a substrate;
a second layer having a plurality of pads on a surface of the second layer set in a second grid for contacting the pogo pin contactors, the plurality of pads in electrical contact with the pogo pins in the first layer; and
wherein the first grid is on a smaller pitch than the second grid.
A fourth aspect of the invention relates to a test structure for testing at least one electrical property of a substrate comprising:
a test bed having a plurality of pogo pin contactors; and
an interposer for maintaining temporary contact between a substrate and the pogo pin contactors, the interposer comprising:
a nonconductive body having first and second adjoining layers;
the first layer containing a plurality of pogo pins set in a first grid for contacting a substrate;
a second layer having a plurality of pads on a surface of the second layer set in a second grid for contacting the pogo pin contactors, the plurality of pads in electrical contact with the pogo pins in the first layer; and
wherein the first grid is on a smaller pitch than the second grid.
REFERENCES:
patent: 5015946 (1991-05-01), Janko
patent: 5187431 (1993-02-01), Libretti
patent: 5418469 (1995-05-01), Turner et al.
patent: 5574382 (1996-11-01), Kimura
patent: 5727954 (1998-03-01), Kato et al.
patent: 5767692 (1998-06-01), Antonella et al.
patent: 5773988 (1998-06-01), Sayre et al.
Bodenweber Paul F.
Comulada Ralph R.
Farooq Mukta S.
Hendricks Charles J.
Hodge Philo B.
Blecker Ira D.
International Business Machines - Corporation
Karlsen Ernest
Kobert Russell M
LandOfFree
Interposer for maintaining temporary contact between a... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Interposer for maintaining temporary contact between a..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Interposer for maintaining temporary contact between a... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2480604