Plated terminations
11195659 · 2021-12-07
Assignee
Inventors
- Andrew P. Ritter (Simpsonville, SC, US)
- Robert H. Heistand, II (St. Johns, FL, US)
- John L. Galvagni (Hendersonville, NC, US)
- Sriram Dattaguru (Myrtle Beach, SC, US)
Cpc classification
H05K2201/09709
ELECTRICITY
C25D5/34
CHEMISTRY; METALLURGY
C23C18/32
CHEMISTRY; METALLURGY
Y10T29/43
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H01C1/14
ELECTRICITY
C23C18/1651
CHEMISTRY; METALLURGY
C25D7/00
CHEMISTRY; METALLURGY
Y10T29/49099
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H01G4/232
ELECTRICITY
Y10T29/49002
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
Y10T29/42
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
H05K3/02
ELECTRICITY
H05K3/403
ELECTRICITY
Y10T29/49101
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
C23C18/1653
CHEMISTRY; METALLURGY
Y10T29/435
GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
International classification
C25D5/34
CHEMISTRY; METALLURGY
H01G4/232
ELECTRICITY
H05K3/02
ELECTRICITY
C23C18/16
CHEMISTRY; METALLURGY
C23C18/32
CHEMISTRY; METALLURGY
C23C28/02
CHEMISTRY; METALLURGY
C25D7/00
CHEMISTRY; METALLURGY
H01C1/14
ELECTRICITY
H01C7/00
ELECTRICITY
Abstract
Improved termination features for multilayer electronic components are disclosed. Monolithic components are provided with plated terminations whereby the need for typical thick-film termination stripes is eliminated or greatly simplified. Such termination technology eliminates many typical termination problems and enables a higher number of terminations with finer pitch, which may be especially beneficial on smaller electronic components. The subject plated terminations are guided and anchored by exposed internal electrode tabs and additional anchor tab portions which may optionally extend to the cover layers of a multilayer component. Such anchor tabs may be positioned internally or externally relative to a chip structure to nucleate additional metallized plating material. External anchor tabs positioned on top and bottom sides of a monolithic structure can facilitate the formation of wrap-around plated terminations.
Claims
1. A method of forming plated terminations on a multi-layer electronic component using a self-determining process, comprising the steps of: providing electrode layers, and providing dielectric layers which are respectively interleaved with said electrode layers and which otherwise form an insulative substrate; exposing selected portions of said electrode layers; and plating termination material on the exposed portions of said electrode layers using said exposed portions of said electrode layers as nucleation points and guides for the termination material; wherein said plating termination material step comprises electrolessly plating, wherein said electrolessly plating comprises depositing a first layer and a second layer by electrolessly plating, wherein said electrolessly plating further includes covering the first layer with an electrically resistive polymeric material before depositing the second layer.
2. A method of forming plated terminations on a multi-layer electronic component using a self-determining process, comprising the steps of: providing electrode layers, and providing dielectric layers which are respectively interleaved with said electrode layers and which otherwise form an insulative substrate; exposing selected portions of said electrode layers; and plating termination material on the exposed portions of said electrode layers using said exposed portions of said electrode layers as nucleation points and guides for the termination material; wherein said plating termination material step comprises electrolessly plating, wherein said electrolessly plating comprises depositing a first layer by electrolessly plating, wherein the step of depositing the first layer comprises submersing the multi- layer electronic component in an electroless copper plating solution to form a copper termination layer, further comprising the step of plating the copper termination layer with an electrically resistive layer.
3. A method as in claim 2, further comprising the step of plating the electrically resistive layer with a conductive layer.
4. A method of forming plated terminations on a multi-layer electronic component using a self-determining process, comprising the steps of: providing electrode layers, and providing dielectric layers which are respectively interleaved with said electrode layers and which otherwise form an insulative substrate; exposing selected portions of said electrode layers; and electrolessly plating termination material on the exposed portions of said electrode layers using said exposed portions of said electrode layers as nucleation points and guides for the termination material; wherein said electrolessly plating termination material step comprises electrolessly plating a first metal layer and then repeated electrolessly plating a second metal layer of other metal, wherein said electrolessly plating further includes covering the first layer with an electrically resistive polymeric material before plating the second layer.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
(1) A full and enabling description of the present subject matter, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
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(20) Repeat use of reference characters throughout the present specification and appended drawings is intended to represent same or analogous features or elements of the invention.
DETAILED DESCRIPTION OF THE EMBODIMENTS
(21) As referenced in the Brief Summary of the Invention section, the present subject matter is directed towards improved termination features for monolithic electronic components.
(22) The subject termination scheme utilizes exposed electrode portions of structures such as monolithic capacitor arrays, multilayer capacitors including those with interdigitated electrode configurations, integrated passive components, and other electronic chip structures. Additional anchor tabs may be embedded within such monolithic components to provide stacked pluralities of exposed internal conductive portions to which plated terminations may be formed and securely positioned along the periphery of a device.
(23) By providing additional anchor tabs on the top and bottom surfaces of a chip device, wrap-around plated terminations may be formed that extend along the side of a chip to the top and bottom layers. Such wrap-around terminations may be desirable in certain applications to facilitate soldering of the chip to a printed circuit board or other suitable substrate.
(24) The subject plating technology and anchor tab features may be utilized in accordance with a plurality of different monolithic components.
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(26) Still further exemplary embodiments of the present subject matter relate to the multilayer capacitor configurations illustrated in
(27) It should be noted that each of the exemplary embodiments as presented herein should not insinuate limitations of the disclosed technology. Features illustrated or described as part of one embodiment can be used in combination with another embodiment to yield further embodiments. Additionally, certain features may be interchanged with similar devices or features not mentioned yet which perform the same, similar or equivalent function.
(28) Reference will now be made in detail to the presently preferred embodiments of the disclosed technology. Referring to the drawings,
(29) The exemplary electrode layer configuration of
(30) An interdigitated capacitor typically consists of a plurality of electrode layers, such as those shown in
(31) Exemplary IDC embodiment 16 may alternatively be viewed as a multilayer configuration of alternating electrode layers and dielectric layers in portion 20 of the device. IDC 16 is typically further characterized by a topmost dielectric layer 22 and bottommost dielectric layer 24 that may generally be thicker than other dielectric layers of IDC configuration 16. Such dielectric layers 22 and 24 act as cover layers to protect the device and provide sufficient bulk to withstand the stress of glass/metal frit that may be fired to a capacitor body. Known capacitor embodiments have utilized the multilayer arrangement of
(32) A multilayer IDC component 16 such as that of
(33) For example, consider the exemplary internal electrode layer configuration illustrated in the exploded view of
(34) Yet another exemplary internal electrode layer configuration provides for electrode tabs that are exposed on four sides of a multilayer interdigitated component. Such internal electrode layers may be similar to the configuration depicted in
(35) A still further exemplary electrode layer configuration and corresponding multilayer capacitor embodiment is depicted in
(36) Referring again to
(37) A thick-film stripe in accordance with such type of termination also typically requires printed application by a termination machine and printing wheel or other suitable component to transfer a metal-loaded paste. Such printing hardware may have resolution limits that make it hard to apply thick-film stripes, especially to smaller chips. A typical existing size for an IDC 16 or other electronic component is about one hundred and twenty mils (thousandths of an inch) by sixty mils along the two opposing sets of sides with a thickness from top to bottom layers of about thirty mils. When more than four terminations need to be applied to a part this size or terminations are desired for a part with smaller dimensions, the resolution levels of specialized termination machinery often becomes a limitation in applying effective termination stripes.
(38) The present subject matter offers a termination scheme that eliminates or greatly simplifies the provision of such typical thick-film termination stripes. By eliminating the less-controlled thick film stripe, the need for typical termination printing hardware is obviated. Termination features in accordance with the disclosed technology focus more on the plated layer of nickel, tin, copper, etc. that is typically formed over a thick-film termination stripe.
(39) Consider the exemplary capacitor array configuration 44 presented in
(40) Plated terminations 50 are thus guided by the positioning of the exposed electrode tabs 46. This phenomena is hereafter referred to as “self-determining” since the formation of plated terminations 50 is determined by the configuration of exposed metallization at selected peripheral locations on multilayer component, or capacitor array, 44. The exposed internal electrode tabs 46 also help anchor terminations 50 to the periphery of capacitor array 44′, which corresponds to a multilayer capacitor embodiment such as 44 of
(41) The plated terminations 50 of
(42) For instance, consider the exploded configuration of exemplary internal metallization illustrated in
(43) With reference to
(44) Internal anchor tabs are preferably aligned in a generally similar column as a stack of internal electrode tabs such that all internal tabs are arranged in common stacks.
(45) For some component applications, it may be preferred that terminations not only extend along the entire width of a component, but also wrap around to the top and bottom layers. In this case, external anchor tabs 70 may be positioned on top and bottom layers of multilayer IDC 60 such that plated terminations can form along the sides and on portions of the top and bottom layers, forming extended solder lands. For example, the provision of embedded internal anchor tabs 58 and 68 and external anchor tabs 70 along with existing exposed electrode tabs 56 in IDC 60, such as depicted in
(46) There are several different techniques that can potentially be used to form plated terminations, such as terminations 72 on multilayer component embodiment 74 of
(47) In accordance with electrochemical deposition and electroless plating techniques, a component such as IDC 74 of
(48) Another technique that may be utilized in accordance with the formation of the subject plated terminations involves magnetic attraction of plating material. For instance, nickel particles suspended in a bath solution can be attracted to similarly conductive exposed electrode tabs and anchor tabs of a multilayer component by taking advantage of the magnetic properties of nickel. Other materials with similar magnetic properties may be employed in the formation of plated terminations.
(49) A still further technique regarding the application of plated termination material to exposed electrode tabs and anchor tabs of a multilayer component involves the principles of electrophoretics or electrostatics. In accordance with such exemplary technology, a bath solution contains electrostatically charged particles. An IDC or other multilayer component with exposed conductive portions may then be biased with an opposite charge and subjected to the bath solution such that the charged particles are deposited at select locations on the component. This technique is particularly useful in the application of glass and other semiconductive or nonconductive materials. Once such materials are deposited, it is possible to thereafter convert the deposited materials to conductive materials by intermediate application of sufficient heat to the component.
(50) One particular methodology for forming plated terminations in accordance with the disclosed technology relates to a combination of the above-referenced plating application techniques. A multilayer component may first be submersed in an electroless plating solution, such as copper ionic solution, to deposit an initial layer of copper over exposed tab portions, and provide a larger contact area. The plating technique may then be switched to an electrochemical plating system which allows for a faster buildup of copper on the selected portions of such component.
(51) In accordance with the different available techniques for plating material to exposed metallization of a multilayer component in accordance with the present technology, different types of materials may be used to create the plated terminations and form electrical connections to internal features of an electrical component. For instance, metallic conductors such as nickel, copper, tin, etc. may be utilized as well as suitable resistive conductors or semi-conductive materials, and/or combinations of selected of these different types of materials. A particular example of plated terminations in accordance with the present subject matter wherein plated terminations comprise a plurality of different materials is discussed with reference to
(52) A first step in the formation of the terminations illustrated in
(53) A still further plating alternative corresponds to forming a layer of metallic plating, and then electroplating a resistive alloy over such metallic plating. Plating layers can be provided alone or in combination to provide a variety of different plated termination configurations. A fundamental of such plated terminations is that the self-determining plating is configured by the design and positioning of exposed conductive portions along the periphery of a component.
(54) Such particular orientation of internal electrode portions and anchor tabs may be provided in a variety of different configurations to facilitate the formation of plated terminations in accordance with the present subject matter. For instance, consider the exemplary internal conductive configuration of
(55) Yet another exemplary multilayer component in accordance with aspects of the present subject matter is represented as component 90 in
(56) A still further application of the presently disclosed technology relates to more general multilayer component configurations, such as depicted in
(57) Another example embodying aspects of the disclosed technology is presented with respect to
(58) An integrated passive component 110, such as that represented by
(59) It should be appreciated that the monolithic component embodiments presented in
(60) It should be appreciated that internal anchor tabs and external anchor tabs may selectively be used for different termination preferences to provide different sizes of side terminations or wrap-around terminations. IDC embodiments displayed and described herein that feature both internal and external anchor tabs may, for instance, only utilize internal anchor tab features when wrap-around terminations are not preferred for a particular application. Different combinations of both internal and external anchor tabs with existing exposed electrode tabs on a variety of different multilayer components can yield numerous potential termination schemes for a device.
(61) While the present subject matter has been described in detail with respect to specific embodiments thereof, it will be appreciated that those skilled in the art, upon attaining an understanding of the foregoing may readily adapt the present technology for alterations to, variations of, and equivalents to such embodiments. Accordingly, the scope of the present disclosure is by way of example rather than by way of limitation, and the subject disclosure does not preclude inclusion of such modifications, variations, and/or additions to the present subject matter as would be readily apparent to one of ordinary skill in the art.