U.S. patent application number 09/350510 was filed with the patent office on 2001-12-13 for apparatus and method for testing a substrate having a plurality of terminals.
Invention is credited to KELLER, TIMOTHY J.
Application Number | 20010050553 09/350510 |
Document ID | / |
Family ID | 23377041 |
Filed Date | 2001-12-13 |
United States Patent
Application |
20010050553 |
Kind Code |
A1 |
KELLER, TIMOTHY J |
December 13, 2001 |
APPARATUS AND METHOD FOR TESTING A SUBSTRATE HAVING A PLURALITY OF
TERMINALS
Abstract
The invention provides apparatus for testing a substrate having
a plurality of terminals. The apparatus includes a frame, a first
arrangement secured to the frame, a mounting arrangement secured to
the frame, and a second arrangement secured to the mounting
arrangement. One of the first and second arrangements is a holder
capable of holding the substrate so that the terminals are located
in the first plane. The other one of the first and second
arrangements is a probe card including a probe card backing member
and a plurality of probes extending from the probe card backing
member, the probes having contact regions located in a second
plane. The mounting apparatus includes at least a first member
which is adjustable relative to the frame so as to pivot the second
arrangement relative to the first arrangement between an
orientation wherein there is an angle between the first and second
planes and an orientation wherein the first and second planes are
substantially parallel to one another. The first and second
arrangements are movable relative to one another between a position
wherein the contact regions are spaced from the terminals and a
position wherein each contact region contacts a respective one of
the terminals.
Inventors: |
KELLER, TIMOTHY J; (SAN
JOSE, CA) |
Correspondence
Address: |
STEPHEN M DE KLERK
BLAKELY SOKOLOFF TAYLOR AND ZAFMAN LLP
12400 WILSHIRE BOULEVARD 7TH FLOOR
LOS ANGELES
CA
90025
|
Family ID: |
23377041 |
Appl. No.: |
09/350510 |
Filed: |
July 9, 1999 |
Current U.S.
Class: |
324/756.05 |
Current CPC
Class: |
G01R 31/2887 20130101;
G01R 1/04 20130101 |
Class at
Publication: |
324/158.1 |
International
Class: |
G01R 001/00 |
Claims
What is claimed:
1. An apparatus for testing a substrate having a plurality of
terminals, comprising: a frame; a first arrangement secured to the
frame; a mounting arrangement secured to the frame; a second
arrangement secured to the mounting arrangement, one of the first
and second arrangements being a holder capable of holding the
substrate so that the terminals are located in a first plane, and
the other one of the first and second arrangements being a probe
card including a probe card backing member and a plurality of
probes extending from the probe card backing member, the probes
having contact regions located in a second plane, wherein: (i) the
mounting apparatus includes at least a first member which is
adjustable relative to the frame so as to pivot the second
arrangement relative to the first arrangement between an
orientation wherein there is an angle between the first and second
planes and an orientation wherein the first and second planes are
substantially parallel to one another; and (ii) the second
arrangement being movable relative to the frame between a position
wherein the contact regions are spaced from the terminals and a
position wherein each contact region contacts a respective one of
the terminals.
2. An apparatus according to claim 1 further comprising: a
controller which receives a signal indicating an orientation of the
first plane while the second arrangement is moved towards the
position wherein each contact region contacts a respective one of
the terminals, and controls the first member so as to maintain the
orientation of the first plane parallel to the orientation of the
second plane while the second arrangement is moved towards the
position wherein each contact region contacts a respective one of
the terminals.
3. An apparatus according to claim 1 wherein the second arrangement
pivots about a first axis and the mounting apparatus includes at
least a second member which is adjustable relative to the frame so
as to pivot the second arrangement relative to the first
arrangement, about a second axis which is at an angle relative to
the first axis, between an orientation wherein there is an angle
between the first and second planes and an orientation wherein the
first and second planes are substantially parallel to one
another.
4. An apparatus according to claim 1 further comprising: a member
which is adjustable so as to rotate the second arrangement relative
to the first arrangement without changing the angle between the
first and second planes.
5. An apparatus according to claim 1 wherein the mounting apparatus
moves the second arrangement towards the first arrangement so as to
bring the contact regions into contact with the terminals.
6. An apparatus according to claim 1 further comprising: an
electrical tester within communication with the probes so as to be
capable of testing the substrate by providing electrical signals
through the probes and the terminals to the substrate.
7. An apparatus according to claim 1 further comprising: at least
one detector capable of detecting the location of the first plane,
and capable of detecting the location of the second plane, a
controller which receives information from the detector of the
locations of the first and second planes, the controller being
capable of adjusting the first member relative to the frame so as
to adjust the first and second planes relative to one another
between the orientation wherein there is an angle between the first
and second planes and the orientation wherein the first and second
planes are substantially parallel.
8. An apparatus according to claim 1 wherein the first arrangement
is the probe card and the second arrangement is the holder.
9. An apparatus for testing a substrate having a plurality of
terminals, comprising: a frame; a probe card secured to the frame,
the probe card having a probe card backing member and a plurality
of probes extending from the probe card backing member, the probes
having contact regions located in a first plane; a mounting
arrangement secured to the frame; a holder secured to the mounting
arrangement, the holder being capable of holding the substrate so
that the terminals are located in a second plane, wherein: (i) the
mounting arrangement includes at least a first member which is
adjustable relative to the frame so as to pivot the holder relative
to the frame between a first orientation wherein there is an angle
between the first and second planes and an orientation wherein the
first and second planes are substantially parallel to one another;
and (ii) the probe card and the holder are movable relative to one
another between a position wherein the contact regions are spaced
from the terminals and a position wherein each contact region
contacts a respective one of the terminals.
10. The apparatus of claim 9 wherein the holder is movable relative
to the frame between the position wherein the contact regions are
spaced from the terminals and the position wherein each contact
region contacts a respective one of the terminals.
11. An apparatus for testing a substrate having a plurality of
terminals, comprising: a frame; a first arrangement secured to the
frame; a plurality of members secured to the frame each member
being adjustable relative to the frame; and a second arrangement
secured to the members, one of the first and second arrangements
being a holder capable of holding the substrate so that the
terminals are located in a first plane, and the other one of the
first and second arrangements being a probe card including a probe
card backing member and a plurality of probes extending from the
probe card backing member, the probes having contact regions
located in a second plane, wherein the members are selectively
adjustable so as to be capable of: (i) pivoting the second
arrangement about a first axis between an orientation wherein there
is an angle between the first and second planes and an orientation
wherein the first and second planes are substantially parallel to
one another; (ii) pivoting the second arrangement about a second
axis, which is at an angle relative to the first axis, between an
orientation wherein there is an angle between the first and second
planes and an orientation wherein the first and second planes are
substantially parallel to one another; (iii) rotating the second
member without changing an angle between the planes; (iv) moving
the second arrangement so that the first and second planes move
past one another in a first direction; (v) moving the second
arrangement so that the first and second planes move past one
another in a second direction which is transverse to the first
direction; and (vi) moving the second arrangement towards and away
from the first arrangement without changing an angle between the
planes.
12. An apparatus according to claim 11 wherein each member is an
extensible arm.
13. An apparatus according to claim 12 comprising at least six of
the extensible arms.
14. An apparatus according to claim 13 wherein extension of all the
arms causes movement of the second arrangement towards the first
arrangement.
15. An apparatus according to claim 11 wherein the first
arrangement is the probe card and the second arrangement is the
holder.
16. An apparatus according to claim 11 further comprising: an
electrical tester within communication with the probes so as to be
capable of testing the substrate by providing electrical signals
through the probes and the terminals to the substrate.
17. An apparatus according to claim 11 further comprising: at least
one detector capable of deleting the location of the first plane
and detecting the location of the second plane, a controller which
receives information from the detector of the locations of the
first and second planes, the controller being capable of adjusting
the first member relative to the frame so as to adjust the first
and second planes relative to one another between the orientation
wherein there is an angle between the first and second planes and
the orientation wherein the first and second planes are
substantially parallel.
18. An apparatus for testing a substrate having a plurality of
terminals, comprising: a frame; a first arrangement secured to the
frame; six extensible arms, each arm having a first end secured to
the frame for pivotal movement in more than one direction; a second
arrangement secured to second ends, opposing the first ends of each
of the six extensible arms, for pivotal movement in more than one
direction relative to each respective arm, one of the first
arrangement and the second arrangement being a holder capable of
holding the substrate and the other one of the first arrangement
and the second arrangement being a probe card including a probe
card backing member and a plurality of probes extending from the
backing member wherein the members are selectively adjustable so as
to be capable of moving the second arrangement relative to the
first arrangement, the first and second arrangement being movable
relative to one another between a position wherein contact regions
of the probes are spaced from the terminals, and a position wherein
each one of the contact regions contacts a respective one of the
terminals.
19. An apparatus for testing a substrate having a plurality of
terminals, comprising: a frame; a first arrangement secured to the
frame; six extensible arms, each arm having a first end secured to
the frame for pivotal movement in more than one direction; a second
arrangement secured to second ends, opposing the first ends, of
each of the six extensible arms, for pivotal movement in more than
one direction relative to each respective arm, one of the first
arrangement and the second arrangement being a holder capable of
holding the substrate so that the terminals are located in a first
plane, and the other one of the first and second arrangements being
a probe card including a probe card backing member and a plurality
of probes extending from the backing member, the probes having
contact regions located in a second plane, wherein the members are
selectively adjustable so as to be capable of: (i) pivoting the
second arrangement about a first axis between an orientation
wherein there is an angle between the first and second planes and
an orientation wherein the first and second planes are
substantially parallel to one another; (ii) pivoting the second
arrangement about a second axis, which is at an angle relative to
the first axis, between an orientation wherein there is an angle
between the first and second planes and an orientation wherein the
first and second planes are substantially parallel to one another;
(iii) rotating the second member without changing an angle between
the planes; (iv) moving the second arrangement so that the first
and second planes move past one another in a first direction; (v)
moving the second arrangement so that the first and second planes
move past one another in a second direction which is transverse to
the first direction; and (vi) moving the second arrangement towards
and away from the first arrangement without changing an angle
between the planes; at least one detector capable of detecting the
location of the first plane and the location second plane; a
controller receiving data from the detector of the location of the
first and second planes, the controller being capable of
controlling the six extensible arms so that the extensible arms:
(i) pivot the second arrangement so as to position the first and
second planes parallel to one another; (ii) rotate the first and
second planes relative to one another; (iii) move the first and
second planes past one another so as to position a selected group
of the terminals over the probes, the rotation ensuring alignment
between selected ones of the probes and selected ones of the
terminals, and the pivoting ensuring that the probes are
substantially equidistantly spaced from the terminals; and (iv)
move the first and second planes toward one another so that a
respective one of the contact regions contacts a respective one of
the terminals.
20. A method of testing a substrate having a plurality of
terminals, comprising: moving a member thereby pivoting a probe
card and the substrate relative to one another between an
orientation wherein there is an angle between a first plane in
which contact regions of probes of a probe card are located and a
second plane in which the terminal are located, and an orientation
wherein the first and second planes are substantially parallel to
one another; and again moving the member thereby moving the probe
card and the substrate towards one another until each contact
region contacts a respective one of the terminals.
21. A method according to claim 20 further comprising: rotating the
probe card and the substrate relative to one another.
22. A method according to claim 21 wherein the probe card and the
substrate are rotated relative to one another without changing an
angle between the planes.
23. A method according to claim 20 further comprising: moving the
probe card and the substrate past one another in a first
direction.
24. A method according to claim 23 further comprising: moving the
probe card and the substrate past one another in a second direction
which is transverse to the first direction.
Description
BACKGROUND OF THE INVENTION
[0001] 1. Field of the Invention
[0002] This invention relates to an apparatus for testing a
substrate having a plurality of terminals, and to a method of
testing a substrate having a plurality of terminals.
[0003] 2. Discussion of Related Art
[0004] Electronic circuits are often made by manufacturing a
plurality of electronic devices such as transistors, capacitors,
diodes, etc. in and on a semiconductor wafer. The devices are
interconnected with one another in an integrated circuit by metal
lines that are deposited on the wafer. A plurality of terminals are
formed on a surface of the wafer and are connected to the metal
lines. Electric signals can be provided to or received from the
integrated circuit through the terminals.
[0005] A number of the integrated circuits are usually formed in
and on a single wafer. The integrated circuits are located in the
form of dice in rows and columns on the wafer. The wafer is
subsequently sawed so that the dice are singulated from one
another.
[0006] Before the wafer is sawed, the integrated circuit of each
die is tested for defects. A probe card having a plurality of
probes is used for making an electrical connection to the
terminals. Each probe has a contact region which contacts a
respective one of the terminals. The probes are connected to an
electrical tester. The electrical tester provides signals through
the probes and the terminals to the integrated circuit, and
receives signals from the integrated circuit through the terminals
and the probes.
[0007] Due to many factors, some of which are discussed
hereinbelow, proper contact between the probes and the terminals is
often difficult to obtain. Contact regions of the probes may, for
example, be located in one plane and the terminals may be located
in another plane which is not parallel to the plane of the contact
regions. When the terminals and the contact regions are moved into
engagement with the terminals, some probes may create more force on
some terminals than others. In more extreme situations proper
contact between a probe and a terminal is not provided. Other
problems such as rotational or positional misalignment may also
occur.
SUMMARY OF THE INVENTION
[0008] The invention provides an apparatus for testing a substrate
having a plurality of terminals. The apparatus includes a frame, a
first arrangement secured to the frame, a mounting arrangement
secured to the frame, and a second arrangement secured to the
mounting arrangement. One of the first and second arrangements is a
holder capable of holding the substrate so that the terminals are
located in the first plane. The other one of the first and second
arrangements is a probe card including a probe card backing member
and a plurality of probes extending from the probe card backing
member, the probes having contact regions located in a second
plane. The mounting apparatus includes at least a first member
which is adjustable relative to the frame so as to pivot the second
arrangement relative to the first arrangement between an
orientation wherein there is an angle between the first and second
planes and an orientation wherein the first and second planes are
substantially parallel to one another. The second arrangement is
movable relative to the frame between a position wherein the
contact regions are spaced from the terminals and a position
wherein each contact region contacts a respective one of the
terminals.
[0009] The apparatus preferably includes a controller which
receives a signal indicating an orientation of the first plane
while the second arrangement is moved towards the position wherein
each contact region contacts a respective one of the terminals. The
controller controls the first member so as to maintain the
orientation of the first plane parallel to the orientation of the
second plane while the second arrangement is moved towards the
position wherein each contact region contacts a respective one of
the terminals.
[0010] The second arrangement preferably pivots about a first axis
and the mounting arrangement preferably further includes at least a
second member which is adjustable relative to the frame so as to
pivot the second arrangement, relative to the first arrangement,
about a second axis which is at an angle relative to the first
axis, between an orientation wherein there is an angle between the
first and second planes and an orientation wherein the first and
second planes are substantially parallel to one another.
[0011] The apparatus may further include a member which is
adjustable so as to rotate the second arrangement relative to the
first arrangement without necessarily changing an angle between the
first and second planes.
[0012] The mounting arrangement may move the second arrangement
towards the first arrangement so as to bring the contact regions
into contact with the terminals.
[0013] The apparatus may further include an electrical tester
within communication with the probes so as to be capable of testing
the substrate by providing electrical signals through the probes
and the terminals to the substrate.
[0014] The apparatus may further include at least one detector
capable of detecting the location of the first plane, and detecting
the location of the second plane. A controller may form part of the
apparatus and may receive information from the detector of the
locations of the first and second planes. The controller may be
capable of adjusting the first member relative to the frame so as
to adjust the first and second planes relative to one another
between the orientation wherein there is an angle between the first
and second planes and the orientation wherein the first and second
planes are substantially parallel.
[0015] The first arrangement is preferably the probe card and the
second arrangement is preferably the holder.
[0016] The invention also provides an apparatus for testing a
substrate having a plurality of terminals, the apparatus including
a frame, a probe card, a mounting arrangement, and a holder. The
probe card is secured to the frame and has a probe card backing
member and a plurality of probes extending from the probe card
backing member. The probes have contact regions located in a first
plane. The mounting arrangement includes at least a first member
which is adjustable relative to the frame so as to pivot the holder
relative to the frame between a first orientation wherein there is
an angle between the first and second planes and an orientation
wherein the first and second planes are substantially parallel to
one another. The probe card and the holder are movable relative to
one another between a position wherein the contact regions re
spaced from the terminals and a position wherein each contact
regions contacts a respective one of the terminals.
[0017] The holder may be movable relative to the frame between the
position wherein the contact regions are spaced from the terminals
and the position wherein each contact region contacts a respective
one of the terminals.
[0018] The invention also provides an apparatus for testing a
substrate having a plurality of terminals. The apparatus includes a
frame, a first arrangement secured to the frame, a plurality of
members secured to the frame, each member being adjustable relative
to the frame, and a second arrangement secured to the members. One
of the first and second arrangements is a holder capable of holding
the substrate so that the terminals are located in a first plane.
The other one of the first and second arrangements is a probe card
including a probe card backing member and a plurality of terminals
extending from the probe card backing member, the probes having
contact regions located in a second plane. The members are
selectively adjustable so as to be capable of pivoting the second
arrangement about a first axis between an orientation wherein there
is an angle between the first and second planes and an orientation
wherein the first and second planes are substantially parallel to
one another, pivoting the second arrangement about a second axis,
which is at an angle relative to the first axis, between an
orientation wherein there is an angle between the first and second
planes and an orientation wherein the first and second planes are
substantially parallel to one another, rotating the second
arrangement without necessarily changing an angle between the
planes, moving the second arrangement so that the first and second
planes move past one another in a first direction, moving the
second arrangement so that the first and second planes move past
one another in a second direction which is transverse to the first
direction, and moving the second arrangement towards and away from
the first arrangement without necessarily changing an angle between
the planes.
[0019] Each member is preferably an extensible arm.
[0020] At least six extensible arms may be provided.
[0021] Extension of all the arms may cause movement of the second
arrangement towards the first arrangement.
[0022] Preferably, the first arrangement is the probe card and the
second arrangement is the holder.
[0023] The apparatus may further include an electrical tester which
is in communication with the probes so as to be capable of testing
the substrate by providing electrical signals through the probes
and the terminals to the substrate.
[0024] The apparatus may further include at least one detector
capable of detecting the location of the first plane and capable of
detecting the location of the second plane. A controller may form
part of the apparatus and is capable of receiving information from
the detector of the locations of the first and second planes. The
controller is capable of adjusting the first member relative to the
frame so as to adjust the first and second planes relative to one
another between the orientation wherein there is an angle between
the first and second planes and the orientation wherein the first
and second planes are substantially parallel.
[0025] The invention also provides an apparatus for testing a
substrate having a plurality of terminals, including a frame, a
first arrangement, six extensible arms, and a second arrangement.
The first arrangement is secured to the frame. Each one of the six
extensible arms has a first end secured to the frame for pivotal
movement in more than one direction. The second arrangement is
secured to second ends, opposing the first ends, of each of the six
extensible arms, for pivotal movement in more than one direction
relative to each respective arm. One of the first arrangement and
the second arrangement is a holder capable of holding the
substrate. The other one of the first arrangement and the second
arrangement is a probe card including a probe card backing member
and a plurality of probes extending from the backing member. The
members are selectively adjustable so as to be capable of moving
the second arrangement relative to the first arrangement. The first
and second arrangements are movable relative to one another between
a position wherein contact regions of the probes are spaced from
the terminals, and a position wherein each one of the contact
regions contacts a respective one of the terminals.
[0026] The invention also provides an apparatus for testing a
substrate having a plurality of terminals, including a frame, a
first arrangement secured to the frame, six extensible arms, each
arm having a first end secured to the frame for pivotal movement in
more than one direction, a second arrangement secured to second
ends, opposing the first ends, of each of the six extensible arms
for pivotal movement in more than one direction relative to each
respective arm, at least one detector, and a controller. One of the
first and second arrangements is a holder capable of holding the
substrate so that the terminals are located in a first plane, and
the other one of the first and second arrangements is a probe card
including a probe card backing member and a plurality of probes
extending from the probe card backing member. The probes have
contact regions located in a second plane. The members are
selectibly adjustable relative to one another so as to be capable
of pivoting the second arrangement about a first axis between an
orientation wherein there is an angle between the first and second
planes and an orientation wherein the first and second planes are
substantially parallel to one another, pivoting the second
arrangement about a second axis, which is at an angle relative to
the first axis, between an orientation wherein there is an angle
between the first and second planes and an orientation wherein the
first and second planes are substantially parallel to one another,
rotating the second member without necessarily changing an angle
between the planes, moving the second arrangement so that the first
and second planes move past one another in a first direction,
moving the second arrangement so that the first and second planes
move past one another in a second direction which is transverse to
the first direction, and moving the second arrangement towards and
away from the first arrangement without necessarily changing an
angle between the planes. The detector is capable of detecting the
location of the first plane and the location of the second plane.
The controller receives data from the detector of the location of
the first and second planes. The controller is capable of
controlling the six extensible arms so that the extensible arms
pivot the second arrangement so as to position the first and second
planes parallel to one another, rotate the first and second planes
relative to one another, move the first and second planes past one
another so as to position a selected group of the terminals over
the probes, the rotation ensuring alignment between selected ones
of the probes and selected ones of the terminals, and the pivoting
ensuring that the probes are substantially equidistantly spaced
from the terminals, and moving the first and second planes toward
one another so that a respective one of the contact regions
contacts a respective one of the terminals.
[0027] The invention also provides a method of testing a substrate
having a plurality of terminals. The method includes moving a
member, thereby pivoting a probe card and the substrate relative to
one another between an orientation wherein there is an angle
between a first plane in which contact regions of the probe cards
are located and a second plane in which the terminals are located,
and an orientation wherein the first and second planes are
substantially parallel to one another, and again moving the member
thereby moving the probe card and the substrate towards one another
until each contact region contacts a respective one of the
terminals.
[0028] The method may further include rotating the probe card and
the substrate relative to one another. The probe card and the
substrate may be rotated relative to one another without changing
an angle between the planes.
[0029] The method may further include moving the probe card and the
substrate past one another in a first direction.
[0030] The method may further include moving the probe card and the
substrate past one another in a second direction which is
transversed to the first direction.
BRIEF DESCRIPTION OF THE DRAWINGS
[0031] The invention is further described by way of example with
reference to the accompanying drawings wherein:
[0032] FIG. 1 is a side view illustrating an apparatus, according
to an embodiment of the invention, which is used for testing a
substrate having a plurality of terminals;
[0033] FIG. 2 is a perspective view of a base plate, a hexapodal
mounting arrangement, a support plate, and a holder forming part of
the apparatus of FIG. 1;
[0034] FIG. 3 is a plan view of the components shown in FIG. 2;
[0035] FIG. 4 is a perspective view illustrating how the holder can
be pivoted about a horizontal axis;
[0036] FIG. 5 is a perspective view illustrating how the holder can
be rotated about a vertical axis; FIG. 6 is a perspective view
illustrating how the holder can be moved in a horizontal
direction;
[0037] FIG. 7 is a perspective view illustrating how the holder can
be elevated;
[0038] FIG. 8 is a side view illustrating one extensible arm
forming part of the mounting arrangement;
[0039] FIG. 9 is a sectioned side view of the extensible arm;
[0040] FIG. 10 is a block diagram illustrating control features of
the apparatus;
[0041] FIG. 11 is a side view of probes forming part of the
apparatus and a wafer having a plurality of terminals;
[0042] FIG. 12 is a view similar to FIG. 11 after the wafer is
pivoted about at least one horizontal axis;
[0043] FIG. 13 is a view similar to FIG. 12 after the wafer is
moved in a plane of the wafer;
[0044] FIG. 14 is a view similar to FIG. 13 after the wafer is
moved towards the probes;
[0045] FIG. 15 is a view similar to FIG. 14 after the wafer is
moved away from the probes;
[0046] FIG. 16 is a view similar to FIG. 14 after the wafer is
moved so that another one of a number of dice of the wafer is
aligned with the probe; and
[0047] FIG. 17 is a view similar to FIG. 16 after the wafer is
moved towards the probes.
DETAILED DESCRIPTION OF THE INVENTION
[0048] FIG. 1 of the accompanying drawings illustrates an apparatus
20, according to an embodiment of the invention, which is used for
testing a substrate having a plurality of terminals. The apparatus
20 includes a frame 22, a probe card 24, a hexapodal mounting
arrangement 26, a support plate 28, a holder 30, an electrical
tester 32, a probe card camera 34, and a substrate camera 36.
[0049] The frame 22 includes a base plate 35, pillars 38, and a
shelf 40. The base plate 35 is located in a stationary position on
a floor. Each pillar 38 has a lower end secured to the base plate
35 and extends upwardly therefrom. The shelf 40 is secured to upper
ends of the pillars 38. An opening 42 is formed in a central region
of the shelf 40.
[0050] The probe card 24 includes a probe card backing member 44
and probes 46 which are secured to the probe card backing member
44. Each probe 46 has a contact region 48 at a tip thereof which is
slightly lower than a lower surface of a probe card backing member
44. Each probe 46 can bend under spring action so that the contact
region 48 thereof can be depressed against spring action.
[0051] The probe card backing member 44 is secured to a lower
surface of a mounting plate 50. The electrical tester 32 is secured
on top of the mounting plate 50. An electrical wire 52
interconnects a respective one of the probes 46 with the electrical
tester 32. Although only two electrical wires 52 are shown, it
should be understood that there may be hundreds of probes 46 and a
large number of wires may be provided so as to interconnect the
probes 46 with the electrical tester 32. The electrical wires 52
may for example be in a bundle which is about 15 centimeters in
diameter. Because of the large number of electrical wires 52, the
probe card 24 is preferably maintained stationary.
[0052] The mounting plate 50 is located on top of the shelf 40 with
the probe card 24 located within the opening 42. The mounting plate
50 is then secured to the shelf 40.
[0053] The contact regions 48 of the probes 46 are usually located
within the same plane. However, the plane of the contact regions 48
is not necessarily horizontal and is largely dependent on the way
the probes 46 are formed, the way in which the probe card backing
member 44 is secured to the mounting plate 50, and the way in which
the mounting plate 50 is secured to the shelf 40. Other factors may
also influence the positioning and orientation of the plane in
which the contact regions 48 are located. Suffice to say that the
plane in which the contact regions 48 are located is largely
indeterminate after the mounting plate 50 is secured to the shelf
40.
[0054] FIG. 2 and FIG. 3 illustrate the base plate 35, the mounting
arrangement 26, the support plate 28, and the holder 30 in more
detail. The mounting arrangement 26 includes a first extensible arm
to a sixth extensible arm, 60a to 60f respectively. Each extensible
arm 60 includes a tubular member 62 and an elongate member 64 which
is located within the tubular member 62. The elongate member can be
extended from and retracted into the tubular member 62.
[0055] A lower end of the tubular member 62 is mounted to the base
plate 35 by means of a universal joint 66. The universal joint 66
allows for pivoting of the tubular member 62 relative to the base
plate 35 in all directions. Each tubular member 62 of each
extensible arm 60 is mounted to the base plate 35 in a similar
manner.
[0056] An upper end of each elongate member 64 is mounted to the
support plate 28 by means of a universal joint 68. The support
plate 28 can thus pivot to relative to the elongate member 64 in
all directions.
[0057] The holder 30 is secured on top of the support plate 28. The
holder 30 includes a number of suction passages 70. Lower ends of
the suction passages 70 can be connected to a vacuum pump (not
shown). A substrate such as a wafer can be located on top of the
holder 30. The vacuum pump can then be switched on so that air
flows through the suction passages 70 and a vacuum is created on a
lower surface of the wafer. The vacuum ensures nonslip engagement
between the wafer and the holder 30.
[0058] Lower ends of the first and second extensible arms 60a and
60b are located next to one another. Lower ends of the third and
fourth extensible arms 60c and 60d are located next to one another.
Lower ends of the fifth and sixth extensible arms 60e and 60f are
located next to one another. Upper ends of the second and third
extensible arms 60b and 60c are located next to one another. Upper
ends of the fourth and fifth extensible arms 60d and 60e are
located next to one another. Upper ends of the sixth and first
extensible arms 60f and 60a are located next to one another. The
upper ends of the extensible arms 60a to 60f are on average located
closer to one another than lower ends of the extensible arms 60a to
60f.
[0059] A wafer located on the holder 30 can be moved by extending
or retracting the elongate members 64 of the extensible arms 60a to
60f. By selectively extending or retracting selected ones of the
elongate members 64, the wafer can be moved in any desired plane or
about any desired axis. FIG. 4 to FIG. 7 illustrate examples of how
the wafer can be moved by selectively extending or retracting
selected ones of the elongate members 64.
[0060] FIG. 4 illustrates one example of how the wafer can be
pivoted about a horizontal axis. The elongate members of the third
and fourth extensible arms 60c and 60d are retracted while the
elongate members of the first, second, fifth and sixth extensible
arms 60a, 60b, 60e, and 60f remain stationary. The wafer pivots
about a horizontal axis 72. The horizontal axis 72 extends from the
upper ends of the first and second extensible arms 60a and 60b to
upper ends of the fifth and sixth extensible arms 60e and 60f.
[0061] In a similar manner, for example, the elongate members of
the first and second extensible arms 60a and 60b can be retracted
while the elongate members of the third, fourth, fifth, and sixth
extensible arms 60c, 60d, 60e, and 60f remain stationary. The wafer
will then pivot about a horizontal axis extending from near upper
ends of the third and fourth extensible arms 60c and 60d to near
upper ends of the fifth and sixth extensible arms 60e and 60f. By
selectively extending or retracting selected ones of the elongate
members of the extensible arms 60a to 60f, the wafer can therefore
be pivoted about any horizontal axis, located transversely relative
to one another, so that a plane of the wafer can be moved to any
desired orientation relative to a horizontal plane.
[0062] FIG. 5 illustrates how the wafer can be rotated. The wafer
is rotated by retracting the elongate members of the first, third,
and fifth extensible arms 60a, 60c, and 60e, while extending the
elongate members of the second, fourth, and sixth extensible arms
60b, 60d, and 60f. The wafer rotates about a vertical axis 74
without necessarily pivoting about any horizontal axis or movement
in any other direction.
[0063] FIG. 6 illustrates how the wafer can be moved in a
horizontal direction. The elongate members of the first, second,
fifth, and sixth extensible arms 60a, 60b, 60e, and 60f are
extended while the elongate members of the third and fourth
extensible arms 60c and 60d are retracted. The wafer moves in a
horizontal direction 76. The direction is from between the first
and sixth extensible arms 60a and 60f to between the third and
fourth extensible arms 60c and 60d.
[0064] The wafer can be moved in any other direction as required.
For example, the elongate members of the first and second
extensible arms 60a and 60b can be retracted while the elongate
members of the third, fourth, fifth, and sixth extensible arms 60c,
60d, 60e, and 60f are retracted. The wafer will then move in a
horizontal direction from between the first and second extensible
arms 60a and 60b to between the fourth and fifth extensible arms
60d and 60e. The wafer can thus be moved in any desired direction,
located transversely relative to one another, in a plane of the
wafer without necessarily rotating the wafer about a vertical axis
or pivoting the wafer about a horizontal axis.
[0065] FIG. 7 illustrates how the wafer can be elevated or lowered.
The elongate members of all the extensible arms 60a to 60f are
extended to cause movement of the wafer in an upward direction 78.
By retracting the elongate members of all the extensible arms 60a
to 60f, the wafer can be lowered.
[0066] FIG. 4, FIG. 5, FIG. 6, and FIG. 7 illustrate only some
examples of how the wafer can be moved. In addition, it should be
understood that any combination of the movements discussed with
reference to FIG. 4, FIG. 5, FIG. 6, and FIG. 7 is also
possible.
[0067] FIG. 8 and FIG. 9 illustrate one of the extensible arms 60
in more detail. In addition to the tubular member 62 and the
elongate member 64, the extensible arm 60 also includes a motor
housing 80, an electric motor 82 located within the motor housing,
a threaded spindle 84, a bearing nut 86, an apparatus 88 for
detecting rotation of the threaded spindle 84.
[0068] An end of the tubular member 62 is secured to the motor
housing which, in turn, is secured to the universal joint 66. The
electric motor 82 includes a stator 92 and a rotor 94 located
within the stator 92. The rotor 94 can be rotated by supplying
electric power to the stator 92.
[0069] The threaded spindle 84 has one end that is secured to the
rotor 94 and rotates together with the rotor 94. The nut 86 is
mounted to the tubular member 62 for sliding movement along the
tubular member 62 without rotation. The threaded spindle 84 and the
nut 86 are in a ballscrew arrangement. The threaded spindle 84 has
thread on an outer surface thereof and the nut 86 has ball bearings
(not shown) on a inner surface thereof. When the threaded spindle
84 rotates, the thread on the outer surface thereof rolls on the
ball bearings on the inner surface of the nut 86 and causes
movement of the nut 86 along the tubular member 62. An end of the
elongate member 64 is secured to the nut 86 so that the elongate
member 64 extends from or retracts into the tubular member 62 when
the nut 86 moves along the tubular member 62. When one voltage is
supplied to the stator 92, the elongate member 64 extends from the
tubular member 62 and when the voltage is reversed, the elongate
member 64 retracts into the tubular member 62.
[0070] Because of a screw engagement between the threaded spindle
84 and the nut 86, rotation of the rotor 94 translates into very
exact translation of the elongate member 64 relative to the tubular
member 62 (as opposed to, for example, the use of pneumatics or
hydraulics).
[0071] The apparatus 88 includes a disk 100 and a detector 102
which is located adjacent to the disk 100. The disk 100 is secured
to and revolves together with the threaded spindle 84. The detector
102 is located next to an edge of the disk 100. Markings (not
shown) are formed around an edge of the disk 100 which can be
detected by the detector 102. Each time a marking is detected by
the detector 102 a signal is sent to a controller 110. The signal
sent by the detector 102 to the controller 110 is indicative of
rotation of the disk 100 and the threaded spindle 84, and therefore
also indicative of extension or retraction of the elongate member
64 out of or into the tubular member 62.
[0072] The controller 110 controls a power supply 112 which
supplies power to the stator 92. By controlling power supplied to
the stator 92, the controller can make the elongate member 64
extend out of or retract into the tubular member 62. Because of
feedback from the detector 102, the controller can switch the power
supply 112 off when the elongate member 64 has extended or
retracted by a certain predetermined distance.
[0073] FIG. 10 illustrates the arrangement of the controller 110
together with a power supply 112a to 112f and a respective
extensible arm 60a to 60f.
[0074] The controller 110 is typically a computer. A software
program provided on a computer readable medium such as a disk is
loaded into memory into the computer. The program is executable
from memory by a processor of the computer.
[0075] The controller is connected to the power supplies 112a to
112f by a serial port, universal serial bus, firewire or any other
communication channel. The controller 110 can control a respective
one of the power supplies 112a to 112f independently from another.
A respective one of the power supplies 112a to 112f provides power
to a respective one of the extensible arms 60a to 60f. Each
extensible arm has a respective detector (102 in FIG. 9) which
provides feedback to the controller 110.
[0076] The controller 110 also receives input from the probe card
camera 34 and the substrate camera 36. The controller 110 is
connected to cameras by a serial port, universal serial bus,
firewire or any other communication channel. Referring again to
FIG. 1, the probe card camera 34 is secured to the support plate
28. The mounting arrangement 26 can be operated so that the probe
card camera 34 moves to respective ones of the probes 46. The probe
card camera 34 can then detect the positioning of a respective
contact region 48 of respective ones of the probes 46. Utilizing
autofocus and other techniques, the probe card camera 34 can also
measure the distance from the probe card camera 34 to a respective
one of the contact regions 48. The exact coordinates of each
contact region 48 can therefore be determined in three dimensional
space. The coordinates of each contact region 48 is provided to the
controller 110. If the location in three dimensional space of each
contact region 48 can be determined, the controller can calculate a
plane in which the contact regions 48 of the probes 46 are located.
The locations of the contact regions 48 and the plane of the
contact regions 48 is determined relative to the positioning of the
probe card camera 34. Details of the probe card camera 34 and how a
plane is determined can be found in the specification of U.S.
patent application Ser. No. 08/980,595 filed Dec. 1, 1997 and
assigned to the assignee of the present application and
incorporated herein by reference.
[0077] The substrate camera 36 is mounted to a boom 116. The boom
116 is mounted to the frame 22 for pivotal movement in a horizontal
plane. Once a wafer (or other substrate) is located on the holder
30, the substrate camera 36 is swept over the wafer by pivoting the
boom 116 relative to the frame 22. The wafer typically has a
plurality to the terminals on a surface thereof. The substrate
camera 36 operates the same as the probe card camera 34 in that the
substrate camera 36 determines the positioning of each one of a
number of the terminals in three dimensional space, and provides
the coordinates of the terminals to the controller 110. The
controller 110 can then determine the plane, or at least an
approximate plane, in which the terminals are located. The
locations in three dimensional space of the terminals and the plane
of the terminals are determined relative to the location of the
substrate camera 36.
[0078] A detector 118 detects the pivotal positioning of the boom
116 and provides feedback to the controller 110 of the exact
positioning of the boom 116. Because the boom 116 is mounted to the
frame 22 and the detector 118 detects the pivotal position of the
boom 116, the positioning of the substrate camera 36 can thus be
determined with respect to the frame 22.
[0079] The probe card camera 34 is initially aligned with the
substrate camera 36 for calibration purposes. When the probe card
camera 34 is detected by the substrate camera 36, the positioning
of the probe card camera 34 and the substrate camera 36 can be
determined relative to one another. Because the absolute
positioning of the substrate camera 36 relative to the frame 22 is
known, the absolute positioning of the probe card camera 34
relative to the frame 22 is also known. The absolute positioning of
the contact regions 48 and the plane of the contact regions 48 (as
detected by the probe card camera 34), and the absolute positioning
of the terminals of the wafer and the plane of the terminals (as
detected by the substrate camera 36) relative to the frame 22 to
are therefore also known by the controller 110. The controller 110
can then calculate the position of the terminals and the contact
regions 48 relative to one another and control the mounting
arrangement 26 by moving the wafer so that the terminals are in
required locations relative to the contact regions 48.
[0080] FIG. 11 to FIG. 17 illustrate how a wafer can be moved.
[0081] FIG. 11 illustrates the probes 46 and a wafer 120. The
contact regions 48 of the probes 46 are located in a first plane
122. The wafer 120 has a plurality of dice 124. The dice 124 are
arranged in rows and columns. Each die 124 has a plurality of
contact terminals 126 on a surface thereof. The contact terminals
126 of the dice 124 are located in a second plane 128.
[0082] The wafer 120 is then moved so that respective one of the
contact regions 48 are located over the respective ones of the
terminals 126 of one of the dice 124. The wafer is then rotated,
pivoted as shown in FIG. 12, and moved in a plane of the wafer 120
as shown in FIG. 13.
[0083] Rotation of the wafer is described hereinbefore with
reference to FIG. 5. Rotation of the wafer 120 ensures that the
contact regions 48 are not rotationally misaligned with the
terminals 126.
[0084] Referring now to FIG. 12, the wafer 120 is then pivoted in a
direction 130 so that the first and second planes 122 and 128 are
parallel to one another. Pivoting of the wafer 120 should be
evident from the description hereinbefore with reference to FIG. 4.
It should therefore be understood that the first and second planes
122 and 128 are parallel to one another in all directions.
[0085] As shown in FIG. 13, the wafer 120 is then moved in a
direction 132 which is in a plane of the wafer 120. As discussed
with reference to FIG. 6, the wafer 120 can be moved in any
direction in a plane of the wafer 120. The contact regions 48 can
therefore be aligned with terminals 126 on a selected one of the
dice 124 which are located in row and columns on the wafer 120. The
contact regions 48 are equidistantly spaced from the terminals
126.
[0086] As shown in FIG. 14, the wafer 120 is then moved in a
direction 134 so that a respective one of the terminals 126
contacts a respective one of the contact regions. The controller
110 controls extension of the extensible arms 60a to 60f so that
the planes 122 and 128 remain parallel to one another while the
wafer 120 moves towards the probes 46. The terminals 126 therefore
contact all of the contact regions 48 at substantially the same
moment in time. The wafer 120 is then further moved in the
direction 134 to cause deflection of the contact regions 48 against
spring action of the probes 46. While so being moved, the plane 128
of the terminals 126 is maintained in its original orientation by
the controller 110. Because the plane of the terminals 126 is
originally parallel to the plane of the contact regions 48, and
maintained in such an orientation, an equal amount of pressure is
applied by each contact region 48 to a respective terminal 126.
Proper contact between the terminals 126 and the contact regions 48
is ensured.
[0087] The electrical tester 32 can then provide electrical signals
through the electrical wires 52 and the probes 46 to the terminals
126. The terminals 126 are connected to an integrated circuit of
semiconductor electronic devices in the wafer 120. Signals can also
be provided by the integrated circuit through the terminals 126 and
the probes 46 to the electrical tester 32. The electrical tester 32
can thus test the integrated circuit in the die 124.
[0088] As shown in FIG. 15, the wafer can then be moved in a
direction 136 so that the terminals 126 are again spaced from the
contact regions 48.
[0089] The wafer 120 is then moved in a direction 138 so that the
contact regions 48 are aligned with terminals 126 on another one of
the dice 124 in the same row as the die which was tested in FIG.
14.
[0090] As shown in FIG. 17, the wafer 120 can again be moved so
that the terminals 126 of the die 124 is brought into contact with
the contact regions 48 for purposes of testing the die 124.
[0091] The process as shown in FIG. 14 to FIG. 17 can be repeated
until each die in a row is tested. The wafer 120 can then be moved
so that the contact regions 48 are aligned with a die in another
column. All the dice in the new column can then be tested in a
similar manner, whereafter dice in a further column can be tested,
and so on.
[0092] It can be seen from the aforegoing description that the
apparatus 20 provides probing of a substrate wherein a plane of
contact regions of probes is automatically adjusted to be
substantially parallel to a plane of terminals on a substrate, or
"planarized" relative to one another. Proper, uniform contact is
ensured between the probes and the terminals. Such a feature is
very useful for an efficient, fast setup, especially when types of
probe cards and substrates are continually being interchanged, and
for continually re-adjusting planarity as needed. Further, the
co-planarity of the two planes (e.g. how close to being parallel
the two planes are) or the height of each extensible arm may be
monitored during a probing operation (e.g. while a force from a
probe card is pressing against the wafer) and each extensible arm
may be adjusted automatically during the probing operation in order
to keep both planes substantially parallel to each other. That is,
the planes may be kept substantially parallel while the one plane
is caused to be pressed toward the other plane (e.g. the plane of
probes is pressed onto the wafer's surface).
[0093] While certain exemplary embodiments have been described and
shown in the accompanying drawings, it s to be understood that such
embodiments are merely illustrative and not restrictive of the
current invention, and that this invention is not restricted to the
specific constructions and arrangements shown and described since
modifications may occur to those ordinarily skilled in the art. For
example, it may be possible for upper ends of extensible arms of a
hexapodal mounting arrangement to extend upwardly past a holder for
a substrate and connect to a probe card. The probe card can then be
moved by the extensible arms instead of the holder. Retraction of
the extensible arms will cause engagement between probes of the
probe card and terminals on the substrate. In another embodiment it
may also be possible to hang a probe card from a hexapodal mounting
arrangement. Extension of the arms of the mounting arrangement will
cause engagement between probes of the probe card and terminals on
a substrate. It may also be possible for a holder to be at the top
and a probe card to be at the bottom. One skilled in the art would
appreciate from the teachings of the aforegoing description that
other arrangements are also possible. One skilled in the art would
however also appreciate the benefits of the present invention, in
particular in that the probe card is stationary because of
connection to the electrical tester, and that the holder is at the
bottom for more convenient handling of a substrate.
* * * * *