U.S. patent application number 10/950583 was filed with the patent office on 2005-02-17 for apparatus and method for cleaning probe card contacts.
This patent application is currently assigned to SAMSUNG ELECTRONICS CO., LTD.. Invention is credited to Byun, Soo-Min, Hwang, In-Seok, Ji, Joon-Su, Kim, Byoung-Joo, Kim, Hyung-Koo, Lee, Ho-Yeol.
Application Number | 20050034743 10/950583 |
Document ID | / |
Family ID | 22586656 |
Filed Date | 2005-02-17 |
United States Patent
Application |
20050034743 |
Kind Code |
A1 |
Kim, Byoung-Joo ; et
al. |
February 17, 2005 |
Apparatus and method for cleaning probe card contacts
Abstract
An apparatus and method for cleaning debris and residue from a
multitude of electrical contacts of a test probe card of an
integrated circuit test probe apparatus preferably comprises a
silicon wafer having a grooved surface into which the test probe
card is moved into pressurized contact. The grooved surface
provides a grating structure that when combined with the
pressurized electrical contacts will crush any intervening or
attached residue particles, which will then break into smaller
particles and fall away from the probe card. Pressure and relative
movement of the probe card may be controlled by a variety of
measurement sensors.
Inventors: |
Kim, Byoung-Joo;
(Yongin-City, KR) ; Hwang, In-Seok; (Suwon-city,
KR) ; Lee, Ho-Yeol; (Seoul-City, KR) ; Byun,
Soo-Min; (Yongin-City, KR) ; Kim, Hyung-Koo;
(Kimpo-City, KR) ; Ji, Joon-Su; (Suwon-city,
KR) |
Correspondence
Address: |
LEE & STERBA, P.C.
SUITE 2000
1101 WILSON BOULEVARD
ARLINGTON
VA
22209
US
|
Assignee: |
SAMSUNG ELECTRONICS CO.,
LTD.
Suwon-city
KR
|
Family ID: |
22586656 |
Appl. No.: |
10/950583 |
Filed: |
September 28, 2004 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10950583 |
Sep 28, 2004 |
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10162675 |
Jun 6, 2002 |
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6813804 |
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Current U.S.
Class: |
134/6 |
Current CPC
Class: |
G01R 3/00 20130101; B24B
19/16 20130101; B08B 1/00 20130101 |
Class at
Publication: |
134/006 |
International
Class: |
B08B 007/00 |
Claims
1-12. (Cancelled)
13. A method for cleaning a test probe needle of an integrated
circuit (IC) test probe apparatus, comprising: a) placing a ridged
breaking apparatus in a wafer support cradle of the IC test probe
apparatus; b) applying a motive means to move the test probe needle
into contact with the ridged breaking apparatus; c) applying a
predetermined additional force to move the test probe needle past
the outermost surface of the ridged breaking apparatus, such that
any debris that is attached to the end of the test probe needle is
broken down into smaller residual portions due to the crushing
action of the needle movement against the ridged breaking
apparatus; and d) removing the ridged breaking apparatus from the
wafer support cradle of the IC test probe apparatus.
14. The method as claimed in claim 13, additionally including after
step c) a step of c1) removing the smaller residual portions from
the test probe needle.
15. The method as claimed in claim 13, wherein the motive means is
applied in an orthogonal direction relative to the top surface of
the breaker.
16. The method as claimed in claim 13, wherein the motive means is
applied in a direction that is between about 90 degrees and 135
degrees relative to the top surface of the breaker.
17. The method as claimed in claim 13, wherein the motive means is
applied in a direction that is about 103 degrees relative to the
top surface of the breaker.
18. The method as claimed in claim 13, wherein a plurality of test
probe needles of an integrated circuit (IC) test probe apparatus is
cleaned.
19. A method for cleaning a test probe needle of an integrated
circuit (IC) test probe apparatus, comprising the steps of: a)
placing a ridged breaking apparatus in a wafer support cradle of
the IC test probe apparatus; b) applying a motive means to move the
ridged breaking apparatus into contact with the test probe needle;
c) applying a predetermined additional force to move the ridged
breaking apparatus such that the outermost surface is past the tip
of the needle, such that any debris that is attached to the end of
the test probe needle is broken down into smaller residual portions
due to the crushing action of the ridged breaking apparatus against
the needle; and d) removing the ridged breaking apparatus from the
wafer support cradle of the IC test probe apparatus.
20. The method as claimed in claim 19, additionally including after
step c) a step of c1) removing the smaller residual portions from
the probe needles.
21. The method as claimed in claim 19, wherein the motive means is
applied in an orthogonal direction relative to the top surface of
the breaker.
22. The method as claimed in claim 19, wherein the motive means is
applied in a direction that is between about 90 degrees and about
135 degrees relative to the top surface of the breaker.
23. The method as claimed in claim 19, wherein the motive means is
applied in a direction that is about 103 degrees relative to the
top surface of the breaker.
24. The method as claimed in claim 19, wherein a plurality of test
probe needles of an integrated circuit (IC) test probe apparatus is
cleaned.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] The present invention relates to a cleaning apparatus for an
integrated circuit (IC) testing apparatus, and more particularly to
an apparatus for cleaning probe needles of an IC electrical test
apparatus and method of use thereof.
[0003] 2. Description of Related Art
[0004] In the manufacture of integrated circuits (ICs), a
conventional method for acceptance testing of a manufactured wafer
before dicing the chips typically uses a probe card, which is
mounted on a test probe apparatus. When the probe card is brought
into proximity with the wafer to be tested, each one of a multitude
of electrical "needles" protruding from the probe card provide a
tensioned electrical contact with a unique pad (electrode) formed
on the individual IC chips on the wafer.
[0005] Due to the needle pressure being applied to the probe to
provide satisfactory electrical contact with an aluminum portion of
each IC pad, debris and residue, such as aluminum oxide particles,
are scraped/created on the surface of the wafer. Such debris and
residue adhere to both the chip and the probe, and after multiple
successive tests, a probe can accumulate a significant amount of
such debris and residue. The accumulated debris and residue
typically exhibit low conductivity and inhibit good electrical
contact between the test needles and the IC pads to be tested.
Thus, to provide satisfactory testing, the probe needles require
periodic cleaning to remove such debris and residue from the
needles.
[0006] In a conventional apparatus, a resilient abrasive pad 40 is
used to clean the test probe needles. As shown in FIG. 1, the test
probe 20 is inserted into the pad 40, such that any debris and
residue 101 attached to the needle tips 22 are removed by abrasive
particles 42 in an elastic base material 41 located in the interior
of pad 40, and any remaining smaller particle (dust film) that have
static attachment to the tips of the needles 20 are collected by a
surface dust cover 43 as probe 20 is withdrawn from the pad 40. A
significant disadvantage of such a cleaning method is that the
cleaning pads 40 are expensive and must be changed frequently as
they become loaded/saturated with debris particles and residue
101.
SUMMARY OF THE INVENTION
[0007] According to a preferred embodiment of the present
invention, an inexpensive test probe cleaning apparatus preferably
comprises a grooved silicon wafer that serves as a breaker or
anvil. When the breaker is mounted in a test cradle of a test probe
apparatus in a manner similar to a manufactured wafer to be tested,
application of normal test probe movement and pressure by a
movement controlling means causes debris and residue that may be
attached to any one of the multitude of test probe needles to be
crushed and abraded between the needles and the breaker. The
smaller particles that result from the crushing operation fall away
from the test needles and into the grooves, preferably due to the
force of gravity. Although they do not create an impedance problem,
any debris or residue particles that may still remain on the test
probe needles may be optionally removed or blown away using a
directed quantity of pressurized gas.
[0008] Unprocessed silicon wafers are the preferred choice for the
breaker substrate since they are inexpensive, have a same dimension
as the wafers being tested, thereby not requiring special test
probe calibration for conducting a cleaning process. Further, use
of wafers allows for easy creation of the grooves or ridges in the
upper surface via a simple grinding operation. A preferred profile
of the grooves is a saw-toothed pattern, which would allow for
hard, angled surfaces that will crush any debris, but will deflect
the test probe needles slightly rather than expose them to damage
that may result from using an un-yielding surface.
[0009] A preferable distance from the uppermost point to the
lowermost cavity of the ridged surface is in a range of 0.5 microns
to 5 microns, with a distance between a first peak and a second and
adjacent peak of the ridged surface being in a range of 0.1 microns
to 1.0 microns. For the foregoing dimensions, a preferred
displacement of the test probe coming into contact with the
breaking surface is about 500 microns. The movement controlling
means may comprise a displacement means, such as a motors, gears,
belts, and/or levers and one or more members from the group
consisting of: an optical sensor, a pressure sensor, and a
displacement sensor.
[0010] A method for using such a cleaning tool may comprise: 1)
placing the ridged breaking apparatus in a wafer support cradle of
the IC test probe apparatus; 2) applying force to move the probe
needles into contact with the surface of the ridged breaking
apparatus; 3) applying a predetermined additional force to move the
needles past the outermost surface of the ridged breaking
apparatus, such that any debris that is attached to the end of the
plurality of probe needles is broken into smaller residual portions
by the crushing action of the needle movement against the ridged
breaking apparatus; 4) removing the smaller residual portions from
the probe needles; and 5) removing the ridged breaking apparatus
from the wafer support cradle of the IC test probe apparatus. The
movement of the probe tips into contact with the breaker may be in
an orthogonal direction or in a direction that is at an angle
between about 90 to 135 degrees, more preferably about 103 degrees,
relative to the top surface of the breaker, i.e. a
scraping/abrading angle.
[0011] In an alternate embodiment, a method may feature the
breaking apparatus being moved relative to a plurality of
stationary probe needles. Such movement may be in an orthogonal
direction or in a direction that is at an angle between about 90 to
about 135 degrees, more preferably about 103 degrees, relative to
the top surface of the breaker.
[0012] These and other features of the present invention will be
readily apparent to those of ordinary skill in the art upon review
of the detailed description that follows.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] FIG. 1 illustrates a conventional apparatus for cleaning
integrated circuit test probe needles.
[0014] FIG. 2 illustrates a sectional view of a probe-cleaning tool
according to the present invention.
[0015] FIG. 3 illustrates a sectional view of an abrasive surface
of the probe-cleaning tool shown in FIG. 2.
[0016] FIG. 4 illustrates a flow chart of the steps used by the
embodiments of to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0017] In a preferred embodiment according to the present
invention, a test probe-cleaning tool comprises a conventional
silicon wafer having saw-toothed grooves ground into an upper
surface. When a probe card of a test probe is brought into
pressurized contact with the grooved surface of the wafer, any
material residue that might be attached to a plurality of
electrical conductors of the test probe (i.e. test needles) are
crushed and/or abraded into smaller particles, which then fall away
from the test needles.
[0018] FIG. 2 illustrates a sectional view of an embodiment of a
probe-cleaning tool 48 according to the present invention. To
create probe-cleaning tool 48, a surface of a conventional wafer 50
may be imbedded with grooves 52 to preferably create a saw-tooth
configuration, as shown in FIG. 2. Selection of a conventional
wafer 50 produces an inexpensive cleaning tool 48 that has a same
thickness and diameter as the manufactured wafers being tested,
thus eliminating any need for special calibration of the applied
pressure or the test fixture. The grooves 52 can be created with a
simple grinding operation to create a saw-toothed "breaking"
surface, such as that shown in FIG. 2. An exemplary dimension of
such a saw-tooth groove 52 might comprise a lateral distance
between saw-tooth peaks in a range of 0.1 micron to 1.0 micron,
with a preferable dimension being 0.3 to 0.5 micron. An associated
depth of the saw-tooth groove might be within a range of 0.5 micron
to 5.0 microns, with a preferable dimension being 1.0 to 4.0
micron. Further, for a probe tip having an exemplary diameter in
the range of 10-30 microns, the displacement movement into contact
with grooves 52 would preferably be about 500 microns. Such a
displacement would apply for a probe having an angular orientation
of between about 90 degrees and about 135 degrees, more preferably
about 103 degrees, relative to the top surface of the saw-toothed
wafer.
[0019] To minimize wear on the probe tip 56, an applied breaking
force would preferably be less than a force of abrasion on the
probe tip 56. Further, to insure that any wafer material attached
to a test probe tip 56 is crushed and/or abraded and removed, the
probe tip (needle) is preferably composed of a hard material, such
as a tungsten alloy, and wafer 50 may be "hardened" to a degree
that any residual debris or residue (i.e., conventional silicon
wafer material) would be significantly more likely to be crushed,
rather than the protruding saw-tooth tips of wafer 50.
[0020] As shown in FIG. 2, in the operation of the probe-cleaning
tool 48, a probe tip 56 is brought into pressurized contact with
the saw-toothed silicon wafer 50. Any debris particle and residue
54 that may be attached or secured to probe tip 56 would be
subjected to a crushing and/or abrading pressure between the probe
tip 56 of the probe card 58 of the test probe apparatus 60 and the
grooved saw-toothed breaking surface of the cleaning wafer 50.
[0021] The saw-toothed silicon wafer 50 would be preferably placed
in a test cradle of the test probe apparatus in a like manner as
manufactured integrated circuit undergoing testing. The test probe
apparatus 60 would preferably move probe card 58 having mounted
thereon probe tip 56 having debris and residue to be cleaned to the
crushing surface of the saw-toothed silicon wafer 50. The amount of
pressure applied to crush and/or abrade the debris and residue
particulate may be controlled by a variety of sensing devices,
including pressure sensors, optical sensing devices, and lateral
movement sensors. Movement of probe card 58 may be effected by a
number of conventional mechanical and electrical movement means,
such as appropriate combinations of motors, gears, belts, and
levers, as are known in the art. In an alternate embodiment, the
breaking apparatus may be moved into contact with stationary probe
tips. In still another embodiment, the probe tip may be repeatedly
(for example, 10 times) brought into contact with the breaking
surface, depending on the properties of the wafer material being
used and residue particles being generated.
[0022] Additionally, the probe tips may be roughened to improve
electrical contact, although such step does not degrade the
breaking and cleaning operation. Although the drawing figures and
description feature a vertically moving probe card, various other
conventional probe types, such as cantilever probes and needle
probes, may also be satisfactorily used in accordance with the
present invention.
[0023] The advantage of the present invention is that through the
use of a conventional wafer having simple grooves, all the
operations of a conventional test probe apparatus may be used
without modification. This provides an inexpensive means for
cleaning any accumulated debris. Further, as the cleaning tool 48
wears out, it can be easily and inexpensively replaced with a new
one.
[0024] FIG. 3 illustrates a sectional view of an abrasive surface
of the probe-cleaning tool shown in FIG. 2. Using conventional
grinding techniques, the angled saw-tooth pattern may be realized.
An advantage of a mechanical grinding operation is that the points
of the saw-teeth will tend to be sharper than if the saw-teeth were
created using a chemical process, such as etching. Although etching
may be used as the groove-creation process, sharp edges desired for
a breaking surface are difficult to attain.
[0025] FIG. 4 illustrates a flow chart showing the use of the
cleaning tool 48 of the present invention. After a multitude of
tests on manufactured IC wafers, a cleaning process 60 may be
periodically inserted into the normal manufacturing test process.
After a manufactured wafer is loaded, tested, and unloaded in steps
62, 64, and 66, respectively, the probe cleaning tool 48,
consisting of saw-toothed silicon wafer 50 as shown in FIG. 2 is
loaded into the test probe apparatus in step 68. Pressurized
contact is applied in step 70 to crush and remove debris and
residue, after which cleaning tool 48 is unloaded from the test
probe apparatus in step 72. Wafer testing is resumed with the
loading and testing of a next wafer in steps 74 and 76,
respectively.
[0026] A preferred embodiment of the present invention has been
disclosed herein and, although specific terms are employed, they
are used and are to be interpreted in a generic and descriptive
sense only and not for purpose of limitation. Accordingly, it will
be understood by those of ordinary skill in the art that various
changes in form and details may be made without departing from the
spirit and scope of the invention as set forth in the following
claims.
* * * * *