U.S. patent application number 11/460290 was filed with the patent office on 2006-11-16 for capacitor having separate terminals on three or more sides and methods of fabrication.
This patent application is currently assigned to Intel Corporation. Invention is credited to Chee-Yee Chung, David G. Figueroa, Yuan-Liang Li.
Application Number | 20060256502 11/460290 |
Document ID | / |
Family ID | 21719714 |
Filed Date | 2006-11-16 |
United States Patent
Application |
20060256502 |
Kind Code |
A1 |
Li; Yuan-Liang ; et
al. |
November 16, 2006 |
CAPACITOR HAVING SEPARATE TERMINALS ON THREE OR MORE SIDES AND
METHODS OF FABRICATION
Abstract
A multilayer capacitor comprises separate terminals on at least
three sides, and on as many as six sides. The capacitor can be
fabricated in a large number of different configurations, types,
and sizes, depending upon the target application. The separate
terminals that are disposed on different sides of the capacitor can
be readily coupled to a variety of different adjacent conductors,
such as die terminals (including bumpless terminals or bars), IC
package terminals (including pads or bars), and the terminals of
adjacent discrete components. Methods of fabrication, as well as
application of the capacitor to an electronic assembly, are also
described.
Inventors: |
Li; Yuan-Liang; (Chandler,
AZ) ; Figueroa; David G.; (Mesa, AZ) ; Chung;
Chee-Yee; (Chandler, AZ) |
Correspondence
Address: |
SCHWEGMAN, LUNDBERG, WOESSNER & KLUTH, P.A.
P.O. BOX 2938
MINNEAPOLIS
MN
55402
US
|
Assignee: |
Intel Corporation
|
Family ID: |
21719714 |
Appl. No.: |
11/460290 |
Filed: |
July 27, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10006188 |
Dec 3, 2001 |
|
|
|
11460290 |
Jul 27, 2006 |
|
|
|
Current U.S.
Class: |
361/306.1 |
Current CPC
Class: |
H01G 4/232 20130101 |
Class at
Publication: |
361/306.1 |
International
Class: |
H01G 4/228 20060101
H01G004/228 |
Claims
1. An electronic assembly comprising: a capacitor including a body
having first and second charge-storing elements in its interior,
and having a plurality of planar exterior sides; and P separate
terminals on at least three exterior sides, M of the separate
terminals being coupled to the first charge-storing element, and N
of the separate terminals being coupled to the second
charge-storing element, wherein M, N, and P are positive integers,
and wherein P=M+N; and at least one electrical element having a
plurality of terminals coupled to the P separate terminals of the
capacitor, wherein the at least one electrical element comprises a
planar exterior surface opposing one of the exterior sides of the
capacitor, wherein the at least one electrical element comprises a
conductive bar protruding outwardly from the exterior surface and
coupled to a second exterior side of the capacitor, and wherein the
capacitor is disposed on the exterior surface of the at least one
electrical element.
2. The electronic assembly recited in claim 1, wherein the
capacitor has a thickness, and wherein the conductive bar has a
height approximately equal to the capacitor thickness.
3. The electronic assembly recited in claim 1, wherein the
electrical element is from the group comprising an electrical
component and a substrate.
4. The electronic assembly recited in claim 3, wherein the
electrical component comprises a capacitor.
5. The electronic assembly recited in claim 3, wherein the
electrical component comprises an integrated circuit.
6. The electronic assembly recited in claim 1, wherein the P
separate terminals comprise four separate terminals on four
different ones of the plurality of exterior sides.
7. The electronic assembly recited in claim 1, wherein the P
separate terminals comprise five separate terminals on five
different ones of the plurality of exterior sides.
8. The electronic assembly recited in claim 1, wherein the P
separate terminals comprise six separate terminals on six different
ones of the plurality of exterior sides.
9. The electronic assembly recited in claim 1, wherein the
capacitor body has a geometrical shape of a rectangular solid.
10. A method of fabricating a capacitor having a body with an
interior and a plurality of exterior sides comprising: forming
first and second charge-storing elements that are separated by a
dielectric material; forming first and second terminals coupled to
the first and second charge-storing elements, respectively, and
disposed on first and second ones of the plurality of exterior
sides; forming at least one conductor within the interior; forming
at least one additional conductor within the interior; forming a
third terminal coupled to the first charge-storing element and
disposed on a third one of the plurality of exterior sides, wherein
the third terminal is electrically coupled to the first terminal
only via the first charge-storing element and the at least one
conductor; forming a fourth terminal coupled to the second
charge-storing element and disposed on a fourth one of the
plurality of exterior sides, wherein the fourth terminal is
electrically coupled to the second terminal only via the second
charge-storing element; and forming a fifth terminal coupled to the
second charge-storing element and disposed on a fifth one of the
plurality of exterior sides, wherein the fifth terminal is
electrically coupled to the second terminal only via the second
charge-storing element and the at least one additional
conductor.
11. The method recited in claim 10 and further comprising: forming
a sixth terminal coupled to the first charge-storing element and
disposed on a sixth one of the plurality of exterior sides, wherein
the sixth terminal is electrically coupled to the first terminal
only via the first charge-storing element.
12. The method recited in claim 10, wherein, in forming, the
plurality of exterior sides are of a rectangular solid.
13. A method comprising: positioning a capacitor having separate
terminals on at least three sides on a flat exterior surface of a
substrate; electrically coupling a separate terminal of a first
side to a first terminal on the substrate; electrically coupling a
separate terminal of a second side to a second terminal on the
substrate; and electrically coupling a separate terminal of a third
side to a third terminal on the substrate, wherein, in coupling,
either or both of the second and third terminals comprise a
conductive bar protruding outwardly from the substrate surface.
14. The method recited in claim 13, wherein, in coupling, an
additional separate terminal of the first side is electrically
coupled to an additional terminal on the substrate.
15. The method recited in claim 13, wherein, in coupling, the
separate terminal of the first side is electrically coupled to an
additional terminal on the substrate.
16. A method comprising: positioning a capacitor having P separate
terminals on at least three sides adjacent to a substrate having M
terminals; positioning an electrical element having N terminals
adjacent to the capacitor; and electrically coupling the P separate
terminals to the M terminals and N terminals, wherein M, N, and P
are positive integers, and wherein P=M+N; and wherein, in
positioning, at least one terminal of either or both the substrate
and the electrical element comprises a conductive bar that
protrudes outwardly from a surface of the respective substrate
and/or electrical element.
17. The method recited in claim 16, wherein, in positioning the
capacitor, the capacitor has P separate terminals on at least four
sides.
18. The method recited in claim 16, wherein, in positioning the
capacitor, the capacitor has P separate terminals on at least five
sides.
19. The method recited in claim 16, wherein, in positioning the
capacitor, the capacitor has P separate terminals on at least six
sides.
20. The method recited in claim 16, wherein, in positioning the
capacitor, the M terminals of the substrate comprise at least one
conductive bar.
21. The method recited in claim 16, wherein, in positioning the
capacitor, the M terminals of the substrate comprise two conductive
bars, and the capacitor is positioned between the two conductive
bars.
22. The method recited in claim 16, wherein, in positioning the
electrical element, the N terminals of the electrical element
comprise at least one conductive bar.
23. The method recited in claim 16, wherein, in positioning the
electrical element, the N terminals of the electrical element
comprise two conductive bars, and the two conductive bars are
positioned on either side of the capacitor.
Description
DIVISIONAL APPLICATION
[0001] The present application is a divisional of U.S. patent
application Ser. No. 10/006,188, filed on Dec. 3, 2001, which is
incorporated herein by reference.
RELATED APPLICATIONS
[0002] The present application is related to the following
applications which are assigned to the same assignee as the present
application:
[0003] Ser. No. 10/006,292, entitled "Integrated Circuit Packages
With Sandwiched Capacitors", now U.S. Pat. No. 6,900,991; and
[0004] Ser. No. 11/080,126, entitled "Integrated Circuit Packages
With Sandwiched Capacitors".
TECHNICAL FIELD
[0005] The inventive subject matter relates generally to electronic
components. More particularly, the inventive subject matter relates
to a multi-terminal capacitor, to an electronic assembly that
includes a multi-terminal capacitor, and to fabrication methods
related thereto.
BACKGROUND INFORMATION
[0006] Integrated circuits (ICs) are typically assembled into
packages by physically and electrically coupling them to a
substrate made of organic or ceramic material. One or more ICs or
IC packages can be physically and electrically coupled to a
substrate such as a printed circuit board (PCB) or card to form an
"electronic assembly". The "electronic assembly" can be part of an
"electronic system". An "electronic system" is broadly defined
herein as any product comprising an "electronic assembly".
[0007] Examples of electronic systems include computers (e.g.,
desktops, laptops, hand-helds, servers, Web appliances, routers,
etc.), wireless communications devices (e.g., cellular phones,
cordless phones, pagers, personal digital assistants, etc.),
computer-related peripherals (e.g., printers, scanners, monitors,
etc.), entertainment devices (e.g., televisions, radios, stereos,
tape and compact disc players, video cassette recorders,
camcorders, digital cameras, MP3 (Motion Picture Experts Group,
Audio Layer 3) players, video games, watches, etc.), and the
like.
[0008] In the field of electronic systems there is an incessant
competitive pressure among manufacturers to increase the
performance of their equipment. This is particularly true regarding
the packaging of ICs on substrates, where each new generation of
packaging must provide increased performance, particularly in terms
of an increased number of components and higher clock frequencies,
while generally being smaller or more compact in size.
[0009] An IC substrate may comprise a number of insulated metal
layers selectively patterned to provide metal interconnect lines
(referred to herein as "traces"), and one or more electronic
components mounted on one or more surfaces of the substrate. The
electronic component or components are functionally connected to
other elements of an electronic system through a hierarchy of
electrically conductive paths that include the substrate traces.
The substrate traces typically carry signals that are transmitted
between the electronic components, such as ICs, of the system.
[0010] As the internal circuitry of high performance ICs, such as
processors, operates at higher and higher clock frequencies, noise
in the power and ground lines increasingly reaches an unacceptable
level. This noise can arise due to inductive and capacitive
parasitics, for example, as is well known. To reduce such noise,
capacitors known as decoupling or by-pass capacitors are often used
to provide a stable signal or stable supply of power to the
circuitry.
[0011] As electronic devices continue to advance, there is an
increasing need for higher levels of capacitance at reduced
inductance levels for decoupling, power dampening, and supplying
charge. In addition, there is a need for capacitance solutions that
do not interfere with package connectors of various types, and
which do not limit the industry to certain device sizes and packing
densities. Accordingly, there is a need in the art for alternative
capacitance solutions in the fabrication and operation of
electronic devices and their packages.
[0012] Many types of capacitors are known in the electronic arts.
One known type of capacitor used in electronic assemblies is
referred to a "chip capacitor". Chip capacitors are known, for
example, in dual-terminal configurations. FIG. 1 is a prior art
dual-terminal chip capacitor 1. These are currently available in a
number of different sizes, such as "0402", i.e.
0.040''.times.0.020'' (approx. 1.0 mm.times.0.50 mm). 0402
capacitors typically have a wrap-around terminal on each end, i.e.
a terminal 2 or 3 covers each end and a portion of each side. One
terminal 2 is of a first polarity, and the other terminal 3 is of a
second polarity.
[0013] In addition to dual-terminal chip capacitors, another type
of chip capacitor is referred to as an "interdigitated capacitor".
FIG. 2 is a prior art interdigitated capacitor 4 having several
terminals 5-8 on each of two sides. Terminals 5 and 7 are of a
first polarity type, and terminals 6 and 8 are of a second polarity
type. Terminals of the same polarity type are alternated along two
opposing sides of capacitor 4. Interdigitated, multilayer, ceramic
capacitors are commercially available from AVX, Myrtle Beach, S.C.,
whose URL is currently www-avxcorp-com; TDK Corporation, Mount
Prospect, Ill., whose URL is currently www-tdk-com; and Murata
Electronics, Smyrna, Ga., whose URL is currently www-murata-com.
(To avoid inadvertent hyperlinks, the periods in the preceding URLs
have been replaced by hyphens.)
[0014] Dual-terminal chip capacitors and interdigitated caps, while
adequate for many packaging and other electronic applications, are
not versatile enough to accommodate the design and performance
requirements of many current electronic applications, including the
packaging of high performance ICs.
[0015] For the reasons stated above, and for other reasons stated
below which will become apparent to those skilled in the art upon
reading and understanding the present specification, there is a
significant need in the art for improved multi-terminal capacitors,
for improved electronic assemblies incorporating such
multi-terminal capacitors, and for improved methods of fabricating
such multi-terminal capacitors and electronic assemblies.
BRIEF DESCRIPTION OF THE DRAWINGS
[0016] FIG. 1 is a prior art dual-terminal chip capacitor;
[0017] FIG. 2 is a prior art interdigitated capacitor having
several terminals on each of two sides;
[0018] FIG. 3 is a top view of a multi-terminal capacitor having
separate terminals on three sides, in accordance with an embodiment
of the inventive subject matter;
[0019] FIG. 4 is a bottom view of the multi-terminal capacitor
shown in FIG. 3;
[0020] FIG. 5 is an exploded perspective view of the multi-terminal
capacitor shown in FIG. 3;
[0021] FIG. 6 is a top view of a multi-terminal capacitor having
separate terminals on four sides, in accordance with an embodiment
of the inventive subject matter;
[0022] FIG. 7 is a bottom view of the multi-terminal capacitor
shown in FIG. 6;
[0023] FIG. 8 is an exploded perspective view of the multi-terminal
capacitor shown in FIG. 6;
[0024] FIG. 9 is a top view of a multi-terminal capacitor having
separate terminals on six sides, in accordance with an embodiment
of the inventive subject matter;
[0025] FIG. 10 is a bottom view of the multi-terminal capacitor
shown in FIG. 9;
[0026] FIG. 11 is an exploded perspective view of the
multi-terminal capacitor shown in FIG. 9;
[0027] FIG. 12 is a top view of a multi-terminal capacitor having
separate terminals on at least three sides, in accordance with an
embodiment of the inventive subject matter;
[0028] FIG. 13 illustrates a cross-sectional representation of an
electronic assembly, including an electrical element, a
multi-terminal capacitor having separate terminals on at least
three sides, and a substrate, in accordance with an embodiment of
the inventive subject matter;
[0029] FIGS. 14A and 14B together illustrate a flow diagram of a
method of fabricating a multi-terminal capacitor having separate
terminals on three or more sides, in accordance with an embodiment
of the inventive subject matter;
[0030] FIGS. 15A and 15B together illustrate a flow diagram of a
method of fabricating an electronic assembly comprising a substrate
and a multi-terminal capacitor having separate terminals on three
or more sides, in accordance with an embodiment of the inventive
subject matter; and
[0031] FIGS. 16A, 16B, and 16C together illustrate a flow diagram
of a method of fabricating an electronic assembly comprising a
substrate, an electrical element, and a multi-terminal capacitor
having separate terminals on three or more sides, in accordance
with an embodiment of the inventive subject matter.
DETAILED DESCRIPTION
[0032] In the following detailed description of embodiments of the
inventive subject matter, reference is made to the accompanying
drawings which form a part hereof, and in which is shown by way of
illustration specific preferred embodiments in which the inventive
subject matter may be practiced. These embodiments are described in
sufficient detail to enable those skilled in the art to practice
them, and it is to be understood that other embodiments may be
utilized and that structural, mechanical, compositional, and
electrical changes may be made without departing from the spirit
and scope of the inventive subject matter. The following detailed
description is, therefore, not to be taken in a limiting sense, and
the scope of the inventive subject matter is defined only by the
appended claims.
[0033] The inventive subject matter provides a multilayer capacitor
that has separate terminals on at least three sides, and on as many
as six sides. The capacitors can be fabricated in a large number of
different configurations, types, and sizes, depending upon the
target application.
[0034] The term "separate", as used herein, means that a terminal
is not electrically coupled to another terminal via any element
that is on the exterior of the capacitor. For example, a terminal
that is wrapped around an edge of the capacitor does not thereby
form two "separate" terminals. As another example, terminals that
are only electrically coupled via an element that is on the
interior of the capacitor are "separate" terminals. The term
"separate" can apply to terminals that are on the same side, or on
different sides, of the capacitor.
[0035] For an application, used in a high performance electronic
assembly as described in the Related Applications, the capacitors
are positioned within the mounting region between a die and an IC
package substrate, particularly in a core region containing power
conductors. Through this arrangement, capacitors can be placed
close to the IC to minimize loop inductance for power delivery,
while also minimizing resistance losses. In addition, the use of
ceramic capacitors between the IC and the IC package substrate in
certain embodiments can provide an improved CTE (coefficient of
thermal expansion) match and improved operational reliability.
[0036] The capacitor has terminals on at least three sides, and up
to six sides. These terminals can be coupled to corresponding
adjacent conductors, such as die terminals (including bumpless
terminals), IC package terminals (including pads and/or bars), and
the terminals of adjacent discrete components (including additional
capacitors). Various embodiments of capacitors having separate
terminals on three or more sides are illustrated and described
herein. Methods of fabrication, as well as application of the
capacitors to an electronic assembly, are also described.
[0037] FIG. 3 is a top view of a multi-terminal capacitor 10 having
separate terminals on three sides, in accordance with an embodiment
of the inventive subject matter. Capacitor 10 has two terminals 12
of positive polarity and two terminals 14 of negative polarity on
its upper surface. Terminals 12 and 14 are "separate" terminals as
defined above.
[0038] Capacitor 10 has a terminal 16 of negative polarity on its
left-hand end (refer to FIG. 5), which terminal 16 has an upper
portion 15 that wraps around onto the top of capacitor 10.
Capacitor 10 further has a terminal 19 of positive polarity on its
right-hand end (refer to FIG. 5), which terminal 19 has an upper
portion 18 that wraps around onto the top of capacitor 10. In
another embodiment, terminals 16 and 19 do not have portions that
wrap onto the top of capacitor 10. Terminals 16 and 19 (FIG. 5) are
"separate" terminals.
[0039] FIG. 4 is a bottom view of the multi-terminal capacitor 10
shown in FIG. 3. In the embodiment illustrated, terminal 16 (refer
to FIG. 5) has a lower portion 17 (FIG. 4) that wraps around onto
the bottom of capacitor 10. Terminal 19 (refer to FIG. 5) has a
lower portion 20 (FIG. 4) that wraps around onto the bottom of
capacitor 10. In another embodiment, terminals 16 and 19 do not
have portions that wrap onto bottom of capacitor 10.
[0040] FIG. 5 is an exploded perspective view of the multi-terminal
capacitor 10 shown in FIG. 3. Capacitor 10 comprises upper and
lower layers 31 and 32, respectively, which may be insulators.
Upper layer 31 is often referred to in the art as a "capping
layer", and lower layer 32 is often referred to as a "base
layer".
[0041] Upper layer 31 comprises terminals 12 and 14. Lower layer 32
does not comprise any separate terminals in this embodiment.
However, portion 17 of terminal 16 wraps around onto lower layer
32, and portion 20 of terminal 19 wraps around onto lower layer
32.
[0042] Capacitor 10 also includes four conductive plates 21-24.
Conductive plates 21 and 22 are charge-storing elements to hold an
electrical charge of a first polarity, e.g. a positive charge.
Conductive plates 23 and 24 are charge-storing elements to hold an
electrical charge of a second polarity, e.g. a negative charge.
Conductive plates 21-24 can be fabricated of any suitable material.
For example, they could be formed of a metal such as copper,
aluminum, or of a metal alloy. Conductive plates 21-24 may be
separated by a suitable dielectric material, such as plastic, a
ceramic, a polymer, glass, or air.
[0043] "Suitable", as used herein, means having characteristics
that are sufficient to produce the desired result(s). Suitability
for the intended purpose can be determined by one of ordinary skill
in the art using only routine experimentation.
[0044] Conductive plates 21-24 are generally disposed within the
interior of the body of capacitor 10. In the embodiment shown in
FIG. 5, conductive plates 21 and 22 are offset slightly to the
right, so that they make electrical contact with terminal 19 when
capacitor 10 is assembled. Similarly, conductive plates 23 and 24
are offset slightly to the left, so that they make electrical
contact with terminal 16 when capacitor 10 is assembled.
[0045] Terminals 12 on the upper surface of capacitor 10 are
electrically coupled to conductive plates 21 and 22 by means of a
conductor such as via 41. Via 41 passes through a non-contact or
keep-out area 42 of conductive plate 23 without electrically
contacting conductive plate 23. Similarly, terminals 14 on the
upper surface of capacitor 10 are electrically coupled to
conductive plates 23 and 24 by means of a conductor such as via 43,
which passes through keep-out areas 44 and 45 of conductive plates
21 and 22, respectively. Vias 41 and 43 can be of any suitable
type, geometry, and composition.
[0046] Referring to FIG. 5, although one terminal of each polarity
is illustrated on the ends of capacitor 10, and two terminals of
each polarity are illustrated on the top of capacitor 10, capacitor
10 could have more separate terminals of the same and/or opposite
polarity on its ends, and capacitor 10 could have fewer separate
terminals on its top. For example, capacitor 10 could have only one
terminal 12 and only one terminal 14 on its top.
[0047] FIG. 6 is a top view of a multi-terminal capacitor 100
having separate terminals on four sides, in accordance with an
embodiment of the inventive subject matter. Capacitor 100 has two
terminals 112 of positive polarity and two terminals 114 of
negative polarity on its top. Terminals 112 and 114 are "separate"
terminals as defined above.
[0048] Capacitor 100 has a terminal 116 of negative polarity on its
left-hand end (refer to FIG. 8), which terminal 116 has an upper
portion 115 that wraps around onto the top of capacitor 100.
Capacitor 100 further has a terminal 119 of positive polarity on
its right-hand end (refer to FIG. 8), which terminal 119 has an
upper portion 118 that wraps around onto the top of capacitor 100.
In another embodiment, terminals 116 and 119 do not have portions
that wrap onto the top of capacitor 100. Terminals 116 and 119
(FIG. 8) are "separate" terminals.
[0049] FIG. 7 is a bottom view of the multi-terminal capacitor 100
shown in FIG. 6. Capacitor 100 has two terminals 111 of negative
polarity and two terminals 113 of positive polarity on its lower
surface. Terminals 111 and 113 are "separate" terminals as defined
above.
[0050] In the embodiment illustrated, terminal 116 (refer to FIG.
8) has a lower portion 117 (FIG. 7) that wraps around onto the
bottom of capacitor 100. Terminal 119 (refer to FIG. 8) has a lower
portion 120 (FIG. 7) that wraps around onto the bottom of capacitor
100. In another embodiment, terminals 116 and 119 do not have
portions that wrap onto bottom of capacitor 100.
[0051] FIG. 8 is an exploded perspective view of the multi-terminal
capacitor 100 shown in FIG. 6. Capacitor 100 comprises upper and
lower layers 131 and 132, respectively, which may be insulators.
Upper layer 131 comprises terminals 112 and 114. Lower layer 132
does not comprise any separate terminals in this embodiment.
However, portion 117 of terminal 116 wraps around onto lower layer
132, and portion 120 of terminal 119 wraps around onto lower layer
132.
[0052] Capacitor 100 also includes four conductive plates 121-124.
Conductive plates 121 and 122 are charge-storing elements to hold
an electrical charge of a first polarity, e.g. a positive charge.
Conductive plates 123 and 124 are charge-storing elements to hold
an electrical charge of a second polarity, e.g. a negative charge.
Conductive plates 121-124 can be fabricated of any suitable
material, such as a metal like copper, aluminum, nickel, silver,
gold, tin, or a metal alloy, such as tin-lead, silver-lead, or
silver-paladium. Conductive plates 121-124 may be separated by a
suitable dielectric material, such as any of those mentioned
earlier.
[0053] Conductive plates 121-124 are generally disposed within the
interior of the body of capacitor 100. In the embodiment shown in
FIG. 8, conductive plates 121 and 122 are offset slightly to the
right, so that they make electrical contact with terminal 119 when
capacitor 10 is assembled. Similarly, conductive plates 123 and 124
are offset slightly to the left, so that they make electrical
contact with terminal 116 when capacitor 100 is assembled.
[0054] Terminals 112 on the upper surface of capacitor 100 are
electrically coupled to conductive plates 121 and 122, and to
terminals 113 on the lower surface of capacitor 100, by means of a
conductor such as via 141. Via 141 passes through non-contact or
keep-out areas 142 and 146 of conductive plates 121 and 123,
respectively, without electrically contacting conductive plates 121
or 123. Similarly, terminals 114 on the upper surface of capacitor
100 are electrically coupled to conductive plates 123 and 124, and
to terminals 111 on the lower surface of capacitor 100, by means of
a conductor such as via 143, which passes through keep-out areas
144 and 145 of conductive plates 121 and 122, respectively.
[0055] Referring to FIG. 8, although one terminal of each polarity
is illustrated on the ends of capacitor 100, and two terminals of
each polarity are illustrated on the top and bottom of capacitor
100, capacitor 100 could have more separate terminals of the same
and/or opposite polarity on its ends, and capacitor 100 could have
fewer separate terminals on its top and/or bottom. For example,
capacitor 100 could have only single terminals 112 and terminal 114
on its top, and only single terminals 111 and 113 on its
bottom.
[0056] FIG. 9 is a top view of a multi-terminal capacitor 200
having separate terminals on six sides, in accordance with an
embodiment of the inventive subject matter. Capacitor 200 has two
terminals 212 of positive polarity and two terminals 214 of
negative polarity on its top. Terminals 212 and 214 are "separate"
terminals as defined above.
[0057] Capacitor 200 has a terminal 216 of negative polarity on its
left-hand end (refer to FIG. 1), which terminal 216 has an upper
portion 215 that wraps around onto the top of capacitor 200.
Capacitor 200 further has a terminal 219 of positive polarity on
its right-hand end (refer to FIG. 1), which terminal 219 has an
upper portion 218 that wraps around onto the top of capacitor
200.
[0058] In addition, capacitor 200 has a terminal 252 of positive
polarity on its back side (refer to FIG. 1), which terminal 252 has
an upper portion 251 that wraps around onto the top of capacitor
200. Capacitor 200 further has a terminal 254 (only a portion of
which is illustrated) of negative polarity on its front side (refer
to FIG. 11), which terminal 254 can have an upper portion (not
shown) that wraps around onto the top of capacitor 200.
[0059] In another embodiment, terminals 216 and 219 do not have
portions that wrap onto the top of capacitor 200. Terminals 216,
219, 252, and 254 (FIG. 1) are "separate" terminals. Thus capacitor
200 has separate terminals on six different sides. If a capacitor
having separate terminals on five sides is desired, then separate
terminals can be omitted from one of the sides.
[0060] FIG. 10 is a bottom view of the multi-terminal capacitor 200
shown in FIG. 9. Capacitor 200 has two terminals 211 of negative
polarity and two terminals 213 of positive polarity on its lower
surface. Terminals 211 and 213 are "separate" terminals as defined
above.
[0061] In the embodiment illustrated, terminals 216 and 219 (refer
to FIG. 1) have lower portions 217 and 220, respectively, that wrap
around onto the bottom of capacitor 200. Also, terminals 251 and
254 (refer to FIG. 1) have lower portions 253 and 255,
respectively, that wrap around onto the bottom of capacitor 200. In
another embodiment, terminals 216, 219, 251, and 254 do not have
portions that wrap onto bottom of capacitor 200.
[0062] FIG. 11 is an exploded perspective view of the
multi-terminal capacitor 200 shown in FIG. 9. Capacitor 200
comprises upper and lower layers 231 and 232, respectively, which
may be insulators. Upper layer 231 comprises terminals 212 and 214.
Lower layer 232 comprises terminals 211 and 213.
[0063] Capacitor 200 also includes four conductive plates 221-224.
Conductive plates 221 and 222 are charge-storing elements to hold
an electrical charge of a first polarity, e.g. a positive charge.
Conductive plates 223 and 224 are charge-storing elements to hold
an electrical charge of a second polarity, e.g. a negative charge.
Conductive plates 221-224 can be fabricated of any suitable
material, such as a metal like copper, aluminum, or a metal alloy.
Conductive plates 221-224 may be separated by a suitable dielectric
material, such as any of those mentioned earlier.
[0064] Conductive plates 221-224 are generally disposed within the
interior of the body of capacitor 200. In the embodiment shown in
FIG. 11, conductive plates 221 and 222 are offset slightly to the
right, so that they make electrical contact with terminal 219 when
capacitor 200 is assembled. Similarly, conductive plates 223 and
224 are offset slightly to the left, so that they make electrical
contact with terminal 216 when capacitor 200 is assembled. In
addition, conductive plates 221 and 222 can be offset slightly
towards the rear, so that they make electrical contact with
terminal 252 when capacitor 200 is assembled. Likewise, conductive
plates 223 and 224 can be offset slightly towards the front, so
that they make electrical contact with terminal 254 when capacitor
200 is assembled.
[0065] Terminals 212 on the upper surface of capacitor 200 are
electrically coupled to conductive plates 221 and 222, and to
terminals 213 on the lower surface of capacitor 200, by means of a
conductor such as via 241. Via 241 passes through non-contact or
keep-out areas 242 and 246 of conductive plates 221 and 223,
respectively, without electrically contacting conductive plates 221
or 223. Similarly, terminals 214 on the upper surface of capacitor
200 are electrically coupled to conductive plates 223 and 224, and
to terminals 211 on the lower surface of capacitor 200, by means of
a conductor such as via 243, which passes through keep-out areas
244 and 245 of conductive plates 221 and 222, respectively.
[0066] Referring to FIG. 11, although one terminal of each polarity
is illustrated on the front, back, and ends of capacitor 200, and
two terminals of each polarity are illustrated on the top and
bottom of capacitor 200, capacitor 200 could have more separate
terminals of the same and/or opposite polarity on its front, back,
and ends, and capacitor 200 could have fewer separate terminals on
its top and bottom. For example, capacitor 200 could have only
single terminals 212 and terminal 214 on its top, and only single
terminals 211 and 213 on its bottom.
[0067] FIG. 12 is a top view of a multi-terminal capacitor 300
having separate terminals on at least three sides, in accordance
with an embodiment of the inventive subject matter. On one surface,
capacitor 300 has six terminals that include three terminals 305 of
positive polarity and three terminals 307 of negative polarity. On
a second surface, capacitor 300 has a separate terminal 301 of
positive polarity, and on a third surface, capacitor 300 has a
separate terminal 303 of negative polarity. Although the embodiment
shown in FIG. 12 comprises terminals 301 and 303 on opposite sides
of capacitor 300, in other embodiments the separate terminals could
be on any side. Also, although capacitor 300 comprises terminals
301 and 303 having portions that wrap onto the same side as
terminals 305 and 307, in another embodiments terminals 301 and 303
do not wrap onto the same side as other separate terminals. The
internal structure of capacitor 300 can be similar to that shown
for capacitor 100.
[0068] FIG. 13 illustrates a cross-sectional representation of an
electronic assembly 400, including an electrical element 401, a
multi-terminal capacitor 410 having separate terminals on at least
three sides, and a substrate 430, in accordance with an embodiment
of the inventive subject matter. Electronic assembly 400
illustrates merely one of many possible embodiments in which
capacitors having separate terminals on three or more sides can be
combined with a substrate, an electrical element, or both.
[0069] In this embodiment, capacitor 410 comprises separate
terminals on at least four sides. Namely, capacitor 410 comprises a
first terminal 421 on its left-hand end, and capacitor 410
comprises a second terminal 422 on its right-hand end. In addition,
capacitor 410 comprises a plurality of terminals 413 and 414 in or
on its upper surface, and capacitor 410 comprises a plurality of
terminals 428 and 429 in or on its lower surface. In this
embodiment, the upper and lower surfaces of capacitor 410 are
fabricated from suitable electrical insulators 411 and 441,
respectively.
[0070] Internally, capacitor 410 comprises a plurality of
charge-storing plates 415 and 416. Plates 415 are to store charge
having a first polarity, and plates 416 are to store charge having
a second polarity.
[0071] Terminal 421 is electrically coupled to plates 415.
Terminals 413 and 429 are also electrically coupled to plates 415
by means of conductors or vias 420. Vias 420 pass through
non-contact or keep-out areas, such as keep-out areas 417, in
plates 416.
[0072] Terminal 422 is electrically coupled to plates 416.
Terminals 414 and 428 are also electrically coupled to plates 416
by means of conductors or vias 419. Vias 419 pass through
non-contact or keep-out areas, such as keep-out areas 418, in
plates 415.
[0073] In this embodiment, electrical element 401 comprises a
substrate 402 of electrically insulating material. Electrical
element 401 further comprises a plurality of terminals, including
terminals 405, 406, 409, and 412. Terminals 405, 406, 409, and 412
can be of any suitable type, including conductive bumps or
conductive bars. The terminals of electrical element 401 can be
electrically coupled to corresponding conductors or traces of
electrical element 401. For example, terminal 405 is coupled to
trace 403; terminal 412 is coupled to trace 408; terminal 409 is
coupled to trace 407; and terminal 406 is coupled to trace 404.
Substrate 402 can comprise one or more layers of traces. Many other
configurations of terminals and traces are possible, depending upon
the particular application.
[0074] Electrical element 401 is an electrical component that can
perform any type of function. In one embodiment, electrical element
401 is a processor integrated circuit (IC), which can be of any
type, such as but not limited to a microprocessor, a
microcontroller, a complex instruction set computing (CISC)
microprocessor, a reduced instruction set computing (RISC)
microprocessor, a very long instruction word (VLIW) microprocessor,
a graphics processor, a digital signal processor (DSP), or any
other type of processor or processing circuit. Other types of
electrical elements 401 include a custom circuit, an
application-specific integrated circuit (ASIC), a communications
circuit, and a wireless filter circuit.
[0075] In addition, electrical element 401 can be another capacitor
having separate terminals on three or more sides. In such
embodiment, electrical element 401 can be identical to or different
from capacitor 410.
[0076] Still referring to the embodiment of FIG. 13, substrate 430
can be a printed circuit board (PCB) comprising one or more layers
of traces within an insulating material 437. Substrate 430
comprises a plurality of terminals, including terminals 424, 425,
435, and 436 on or in its upper surface. Terminals 424, 425, 435,
and 436 can be of any suitable type, including conductive pads or
bars. In the embodiment shown, terminals 424 and 425 are conductive
pads, and terminals 435 and 436 are conductive bars (referred to in
some embodiments as "Alternative Bump Metallurgy" (ABM)).
[0077] The terminals of substrate 430 can be electrically coupled
to corresponding conductors or traces of substrate 430. For
example, conductive bars 435 and 436 are coupled to conductors 431
and 432, respectively, which in turn are coupled to terminals 433
and 434, respectively, on the lower surface of substrate 430.
Terminals 424 and 425 are coupled to traces 426 and 427,
respectively.
[0078] As mentioned above, electronic assembly 400 can be
implemented in many different forms. In one embodiment, electronic
assembly 400 comprises capacitor 410 electrically coupled to
electrical element 401. In this embodiment, terminals (such as
terminals 413 and 414) on the upper surface of capacitor 410 are
electrically coupled to corresponding terminals (such as terminals
412 and 409) on electrical element 401. In addition, separate
terminals on opposite sides of capacitor 410 (such as terminals 421
and 422) are electrically coupled to corresponding terminals on
electrical element 401. In this embodiment, the conductive bars 435
and 436 would be formed on and as part of electrical element 401
rather than on and as part of substrate 430.
[0079] In another embodiment, electronic assembly 400 comprises
capacitor 410 electrically coupled to substrate 430. In this
embodiment, terminals (such as terminals 428 and 429) on the lower
surface of capacitor 410 are electrically coupled to corresponding
terminals (such as terminals 424 and 425) on substrate 430. In
addition, separate terminals on opposite sides of capacitor 410
(such as terminals 421 and 422) are electrically coupled to
corresponding terminals on substrate 430. In this embodiment,
terminals 421 and 422 of capacitor 410 are electrically coupled to
conductive bars 435 and 436, respectively, of substrate 430.
[0080] In yet another embodiment, electronic assembly 400 comprises
capacitor 410 electrically coupled to both electrical element 401
and to substrate 430. In such embodiment, the terminals (such as
terminals 428 and 429) on the lower surface of capacitor 410 are
electrically coupled to corresponding terminals (such as terminals
424 and 425) on or in the upper surface of substrate 430. Terminals
on opposite ends of capacitor 410 (such as terminals 421 and 422)
are electrically coupled to conductive bars 435 and 436,
respectively, which can be formed on and as part of either
substrate 430 or electrical element 401. Terminals (such as
terminals 413 and 414) on the upper surface of capacitor 410 are
electrically coupled to corresponding terminals (such as terminals
412 and 409) of electrical element 401. In addition, in an
embodiment wherein conductive bars 435 and 436 are formed on and as
part of substrate 430, terminals 405 and 406 of electrical element
401 are electrically coupled to conductive bars 435 and 436,
respectively, of substrate 430.
[0081] The terminals of the electrical element 401, of the
capacitor 410, and of the substrate 430 can be formed of any
suitable material, including metals or metal alloys known to those
of ordinary skill in the art, such as lead, solder, copper, silver,
aluminum, gold, etc.
[0082] FIGS. 14A and 14B together illustrate a flow diagram of a
method of fabricating a multi-terminal capacitor having separate
terminals on three or more sides, in accordance with an embodiment
of the inventive subject matter. The method starts at 500.
[0083] In 501, a capacitor is constructed having two sets of
charge-storing elements. Each set comprises at least one
charge-storing element. For example, a first set of charge-storing
elements has a first charge-storing element to store a charge
having a first polarity, e.g. a positive polarity. A second set of
charge-storing elements has a second charge-storing element to
store a charge having a second polarity, e.g. a negative polarity.
The sets of charge-storing elements are separated by a dielectric
material, such as any of those mentioned earlier.
[0084] In 503, P separate terminals are formed on at least three of
the external sides of the capacitor. M of the P separate terminals
are coupled to the first charge-storing element(s). N of the P
separate terminals are coupled to the second charge-storing
elements(s). "M", "N", and "P" are positive integers, and P=M+N.
For example, with reference to FIG. 11, there are 4 separate
terminals on the upper surface of capacitor 200, 4 separate
terminals on the lower surface, and separate terminals on each of
the left, right, front, and back sides, giving a total of P=12
separate terminals. M=6 of the 12 terminals are coupled to a first
set of charge-storing elements (e.g. plates 221 and 22), and N=6 of
the 12 terminals are coupled to a second set of charge-storing
elements (e.g. plates 223 and 224)
[0085] The capacitor can be made in different embodiments, having
at least 3, 4, 5, or 6 separate terminals formed on 3, 4, 5, or 6
different exterior sides, respectively, of the capacitor. For
example, FIG. 5 illustrates an embodiment having separate terminals
on 3 sides. FIG. 8 illustrates an embodiment having separate
terminals on 4 sides. And FIG. 11 illustrates embodiments having
separate terminals on either 5 or 6 sides.
[0086] The capacitor can have more than one separate terminal on
each of at least 3 exterior sides. For example, one exterior side
could have 2 separate terminals; another side could have 3 separate
terminals; a third exterior side could have 7 separate terminals; a
fourth exterior side could have just 1 separate terminal; and so
forth.
[0087] The capacitor has a body, which may have any suitable
geometrical shape. In one embodiment, e.g. as shown in FIG. 5, the
capacitor body has the geometrical shape of a rectangular solid.
However, other geometrical solids are possible, such as cylinders,
truncated cones, trapezoidal solids, free-form solids, and the
like. The method ends at 505.
[0088] FIGS. 15A and 15B together illustrate a flow diagram of a
method of fabricating an electronic assembly comprising a substrate
and a multi-terminal capacitor having separate terminals on three
or more sides, in accordance with an embodiment of the inventive
subject matter. The method starts at 600.
[0089] At 601, a capacitor having separate terminals on at least 3
sides is positioned with respect to a substrate.
[0090] At 603, a separate terminal of a first side is electrically
coupled to a first terminal on the substrate. In another embodiment
(e.g. that shown in FIG. 13), 2 separate terminals (428, 429) of a
first side are electrically coupled to first and second terminals
(424, 425), respectively, on the substrate. In yet another
embodiment, one separate terminal of a first side is electrically
coupled to first and second terminals, respectively, on the
substrate. For example, one bar-shaped terminal of a first side of
the capacitor can be electrically coupled to several pads on the
substrate.
[0091] At 605, a separate terminal of a second side is electrically
coupled to a first conductive bar on the substrate. For example,
with reference to FIG. 13, terminal 421 is electrically coupled to
conductive bar 435. In another embodiment, 2 separate terminals of
a second side are electrically coupled to a first conductive bar on
the substrate. For example, 2 separate terminals of a second side
of the capacitor can be electrically coupled to a first conductive
bar on the substrate.
[0092] At 607, a separate terminal of a third side is electrically
coupled to a second conductive bar on the substrate. For example,
with reference to FIG. 13, terminal 422 is electrically coupled to
conductive bar 436. In another embodiment, 2 separate terminals of
a third side are electrically coupled to a second conductive bar on
the substrate. For example, 2 separate terminals of a third side of
the capacitor can be electrically coupled to a second conductive
bar on the substrate. The method ends at 609.
[0093] FIGS. 16A, 16B, and 16C together illustrate a flow diagram
of a method of fabricating an electronic assembly comprising a
substrate, an electrical element, and a multi-terminal capacitor
having separate terminals on three or more sides, in accordance
with an embodiment of the inventive subject matter. The method
starts at 700.
[0094] At 701, a capacitor having "P" separate terminals on at
least 3 exterior sides is positioned adjacent to a substrate having
"M" terminals. In some embodiments, the capacitor has separate
terminals on 4, 5, or 6 sides. The capacitor may have more than one
separate terminal per side. The M terminals on the substrate may
include at least one conductive bar.
[0095] At 703, an electrical element, such as electrical element
401 in FIG. 13, is positioned adjacent to the capacitor. The
electrical element has "N" terminals. The N terminals of the
electrical element may include at least one conductive bar.
[0096] At 705, the capacitor's P separate terminals are
electrically coupled to the M terminals on the substrate and to the
N terminals of the electrical element. This can be done in many
different ways, depending upon the arrangement of terminals on the
capacitor, and upon the arrangement of terminals, including
conductive bars, on the substrate and on the electrical
element.
[0097] In one embodiment, one or more separate terminals of a first
side of the capacitor may be electrically coupled to corresponding
terminals of the substrate. One or more separate terminals of a
second side may be electrically coupled to a first conductive bar
on the substrate. One or more separate terminals of a third side
may be electrically coupled to a second conductive bar on the
substrate. One or more conductive terminals of a fourth side may be
electrically coupled to corresponding terminals of the electrical
element. One or more separate terminals of a fifth side may be
electrically coupled to a first conductive bar on the electrical
element. One or more separate terminals of a sixth side may be
electrically coupled to a second conductive bar on the electrical
element. That is, both the substrate and the electrical element
could have one or more conductive bars in or on their respective
surfaces, to which separate terminals of the same or different
sides of the capacitor could be electrically coupled.
[0098] Many combinations of capacitor terminals, of electrical
element terminals, and of substrate terminals are possible besides
those shown and described. In general, the separate terminals can
be coupled to corresponding terminals and/or conductive bars on the
substrate and/or on the electrical element in any desired
combination. The method ends at 707.
[0099] The exterior sides of the capacitor may be planar, as seen
for example regarding embodiments illustrated in FIGS. 3-13. It
will further be seen from FIG. 13 that the electrical element 401
may have a planar exterior surface opposing the upper exterior side
of the capacitor 410. In addition, FIG. 13 shows that conductive
bars 435 and 436 may protrude outwardly from an upper exterior
surface of the substrate 430. At least one conductive bar 435, 436
may be coupled to an exterior side (e.g., end) of capacitor 410.
Capacitor 410 may be disposed on the upper exterior surface of the
substrate 430. In an embodiment, at least one conductive bar 435,
436 may have a height approximately equal to the thickness of
capacitor 410.
[0100] The operations described above with respect to the methods
illustrated in FIGS. 14A-B, 15A-B, and 16A-C can be performed in a
different order from those described herein.
[0101] The above-described and illustrated details relating to the
number, arrangement, dimensions, and types of terminals, electrical
elements, substrates, and other constituent parts are merely
exemplary of the embodiments illustrated, and they are not meant to
be limiting. Further, the assembly operations and sequencing can be
varied by one of ordinary skill in the art to optimize the
fabrication and performance of the capacitor and/or electronic
assembly.
[0102] FIGS. 1-13 are merely representational and are not drawn to
scale. Certain proportions thereof may be exaggerated, while others
may be minimized. The drawings are intended to illustrate various
implementations of the inventive subject matter that can be
understood and appropriately carried out by those of ordinary skill
in the art.
[0103] The inventive subject matter provides for a multilayer
capacitor that has separate terminals on at least three sides, and
on as many as six sides. The capacitors can be fabricated in a
large number of different configurations, types, and sizes,
depending upon the desired end use application.
[0104] In embodiments, described in the Related Applications, the
capacitors provide high-speed, low inductance capacitive decoupling
in an integrated circuit (IC) package, in which the capacitors are
positioned within the mounting region between a die and an IC
package substrate.
[0105] In another embodiment, a capacitor, having separate
terminals on at least three different sides, is mounted on a
substrate, and an electrical element can optionally be mounted on
the capacitor. Alternatively, the capacitor could be mounted on the
electrical element alone.
[0106] In yet another embodiment, a capacitor, having separate
terminals on up to six different sides, is mounted between
conductive bars on a substrate surface, and the capacitor may be
electrically coupled to the conductive bars, to one or more
terminals on the substrate, to one or more terminals of an
electrical element, and to one or more terminals of adjacent
capacitors. Alternatively, the capacitor could be mounted between
conductive bars on the surface of an electrical element. Or the
capacitor could be mounted between conductive bars that are on both
the substrate and on the electrical element.
[0107] The separate terminals that are disposed on different sides
of the capacitor can be readily coupled to a variety of different
adjacent conductors, such as die terminals (including bumpless
terminals), IC package terminals (including pads and/or bars), and
the terminals of adjacent discrete components (including additional
capacitors). In addition to the types of terminals described above,
any other suitable terminals could be used. The terminals can have
any desired geometry, location on the component, and
composition.
[0108] Methods of fabrication, as well as application of the
capacitors to an electronic assembly, are also described.
[0109] The inventive subject matter allows electronic assemblies
with high performance ICs to be operated at increased clock
frequencies and with higher reliability. An electronic assembly
and/or electronic system that incorporates one or more capacitors
of the inventive subject matter can handle the relatively high
power densities and clock frequencies associated with high
performance ICs, and such assemblies and/or systems are therefore
more commercially attractive.
[0110] As shown herein, the inventive subject matter can be
implemented in a number of different embodiments, including various
types of capacitors, an electronic assembly, and various methods of
fabricating a capacitor and an electronic assembly. Other
embodiments will be readily apparent to those of ordinary skill in
the art. The elements, materials, geometries, dimensions, and
sequence of operations can all be varied to suit particular
manufacturing and packaging requirements.
[0111] While certain structures or operations have been described
herein relative to the reader's perspective, such as "top" or
"bottom", "upper" or "lower", "left" or "right", "front" or "rear",
and so forth, it will be understood that these descriptors are
relative, and that they would be reversed if the particular
structure being described, e.g. a capacitor, IC, substrate, or
package, were inverted, rotated, or viewed in mirror-image.
Therefore, these terms are not intended to be limiting.
[0112] The inventive subject matter is not to be construed as
limited to use in IC packages, and it can be used with any other
type of electronic package where the herein-described features of
the inventive subject matter provide an advantage.
[0113] Although specific embodiments have been illustrated and
described herein, it will be appreciated by those of ordinary skill
in the art that any arrangement that is calculated to achieve the
same purpose may be substituted for the specific embodiment shown.
This application is intended to cover any adaptations or variations
of the inventive subject matter. Therefore, it is manifestly
intended that this inventive subject matter be limited only by the
claims and the equivalents thereof.
* * * * *