Structure with controlled capillary coverage

Abstract

A structure (101) with controlled capillary coverage is provided, comprising a substrate (110) including one or more first contacts (112), a component (130), and an adhesive (140). The component (130) includes one or more second contacts (132) and ribs (133) arranged at a distance from each of the one or more second contacts (132). The component (130) is arranged such that the one or more second contacts (132) are in communication with the one or more first contacts (112), and corresponding surfaces of the substrate (110) and the ribs (133) face each other with a controlled gap height to define a fill space (150). The adhesive (140) is dispensed at discrete points (141), whereby the adhesive (140) is drawn by capillary action to fill the fill space (150).

Description

TECHNICAL FIELD

[0001] The present invention relates generally to surface mounted electrical components, and more particularly to surface mounted electrical component structures with controlled capillary coverage. BACKGROUND

[0002] Surface mounted electrical components are typically mechanically secured to a printed circuit board (PCB) using pins that are inserted into a through-hole defined through the PCB. Surface mounted electrical components can include a housing, and the pins can be part of the housing or can be pressed into the housing after the housing is molded. The pins are typically attached to the board using an adhesive or solder. SUMMARY

[0003] Embodiments of the present invention relate to structures with controlled capillary coverage. The structure includes a substrate including one or more first contacts, a component, and an adhesive. The component includes one or more second contacts and a rib disposed a distance from each of the one or more second contacts. The component is arranged such that the one or more second contacts are in communication with the one or more first contacts, and corresponding surfaces of the substrate and the rib face each other at a controlled gap height to define a fill space. The adhesive is dispensed at discrete points, whereby the adhesive is drawn by capillary action to fill the space.

[0004] The controlled gap height, fluid properties of the adhesive, and the configuration of the rib can establish a pressure of the capillary action.

[0005] The rib can include one or more of a chamfered portion, a discontinuous portion, a tapered portion, and a stepped portion.

[0006] The rib can include a hard-stop element.

[0007] The rib can include an anchoring element that extends partially across the controlled gap height, and the rib can be formed to define an open section into which a column of adhesive is drawn by capillary action.

[0008] The discrete points can be in the fill space, and the adhesive can be drawn by capillary action to fill a remaining portion of the fill space, or the discrete points can be adjacent to the fill space, and the adhesive can be drawn by capillary action to fill the entire fill space.

[0009] The adhesive can be dispensed through a through-hole defined by a body of the component or through a through-hole defined by the substrate.

[0010] One embodiment of the invention relates to a structure with controlled capillary coverage. The structure includes a substrate including one or more first contacts, a component, and one or more of a capillary adhesive, a glue, an epoxy, and an underfill. The component includes one or more second contacts and a rib disposed a distance from each of the one or more second contacts. The rib includes a hard stop element, and the component is arranged such that the one or more second contacts are in communication with the one or more first contacts, and corresponding surfaces of the substrate and the rib face each other at a controlled gap height established by the hard step element to define a fill space. The one or more of the capillary adhesive, the glue, the epoxy, and the underfill are dispensed at discrete points, whereby the one or more of the capillary adhesive, the glue, the epoxy, and the underfill are drawn by capillary action to fill the fill space.

[0011] The controlled gap height, the fluid properties of the one or more of the capillary adhesive, the glue, the epoxy, and the underfill, and the configuration of the rib can establish a pressure of the capillary action.

[0012] The rib can include one or more of a chamfered portion, a discontinuous portion, a tapered portion, and a stepped portion.

[0013] The rib can include an anchoring element that extends partially across the controlled gap height, and the rib can be formed to define an open portion into which a column of the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can be drawn by capillary action.

[0014] The discrete points can be in the fill space, and the one or more of the capillary adhesive, the UF, the glue, and the epoxy can be drawn by capillary action to fill a remaining portion of the fill space, or the discrete points can be adjacent to the fill space, and the capillary adhesive, the adhesive glue, the epoxy, and the underfill can be drawn by capillary action to fill the entire fill space.

[0015] The one or more of the capillary adhesive, the adhesive glue, the epoxy, and the underfill can be dispensed through a via defined by a body of the component or through a via defined by the substrate.

[0016] One embodiment of the invention relates to a structure with controlled capillary coverage. The structure includes a substrate including one or more first contacts, first and second components, and one or more of a capillary adhesive, a glue, an epoxy, and an underfill. The first and second components each include one or more second contacts and a rib at a distance from each of the one or more second contacts. The first component and the second component are each positioned immediately adjacent to each other such that the respective one or more second contacts are in communication with a respective portion of the one or more first contacts, and the respective rib and a respective corresponding surface of the substrate face each other at a controlled gap height to define first and second fill spaces. One or more of the capillary adhesive, the glue, the epoxy, and the underfill are dispensed at first and second discrete points, whereby the one or more of the capillary adhesive, the glue, the epoxy, and the underfill are drawn by capillary action to fill the first and second fill spaces, respectively.

[0017] An embodiment of the invention relates to a method of assembling a structure with controlled capillary coverage. The method includes positioning an element such that its contacts are positioned to be in communication with contacts of a substrate and a rib of the element faces a surface of the substrate, welding the contacts of the element to the contacts of the substrate such that the rib faces the surface at a controlled gap height to define a fill space, and dispensing one or more of a capillary adhesive, a glue, an epoxy, and an underfill at a discrete point, whereby the one or more of the capillary adhesive, the glue, the epoxy, and the underfill are drawn to fill the fill space by capillary action.

[0018] The method can further include setting the controlled gap height, selecting the one or more of the capillary adhesive, the glue, the epoxy, and the underfill for a fluid property, and configuring the rib to establish a pressure of the capillary action.

[0019] The discrete point can be in the fill space and the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can be drawn by capillary action to fill a remaining portion of the fill space, or the discrete point can be adjacent to the fill space and the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can be drawn by capillary action to fill the entire fill space.

[0020] The dispensing of the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can include dispensing through a via defined by the assembly, or dispensing through a via defined by the substrate.

[0021] Embodiments of the invention relate to a method of a structure with controlled capillary coverage. The method includes disposing an element such that its contacts are positioned to be in communication with contacts of a substrate and a rib of the element faces a surface of the substrate, welding the contacts of the element to the contacts of the substrate, disposing a hard stop element between the rib and the surface during the welding such that the rib faces the surface with a controlled gap height established by the hard stop element to define a fill space, and dispensing one or more of a capillary adhesive, a glue, an epoxy, and a underfill at discrete points whereby the one or more of the capillary adhesive, the glue, the epoxy, and the underfill are drawn to fill the fill space by capillary action.

[0022] The method can also include disposing the controlled gap height, selecting the one or more of the capillary adhesive, the glue, the epoxy, and the underfill for fluid properties, and configuring the rib to establish a pressure for the capillary action.

[0023] The discrete points can be in the fill space and the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can be pulled to fill a remaining portion of the fill space by capillary action, or the discrete points can be adjacent to the fill space and the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can be drawn to fill the entire fill space by capillary action.

[0024] The dispensing of the one or more of the capillary adhesive, the glue, the epoxy, and the underfill can include dispensing through a via defined by the assembly, or can include dispensing through a via defined by passing through the substrate.

[0025] Additional technical features and benefits are realized through the techniques of the present invention. Embodiments of the invention are described in detail below with reference to the attached drawing figures, and are to be considered as part of the claimed subject matter. For a better understanding, refer to the detailed description and to the drawings. BRIEF DESCRIPTION OF DRAWINGS

[0026] The specifics of the exclusive rights described herein are particularly pointed out and distinctly claimed in the claims at the conclusion of the specification. The foregoing and other features and advantages of embodiments of the present invention are apparent from the following detailed descriptions, taken in conjunction with the accompanying drawings, in which:

[0027] Figure 1A is a perspective view of a structure with controlled capillary coverage in accordance with embodiments of the invention;

[0028] Figure 1B is an enlarged side view showing details of the circled portion of Figure 1A

[0029] ​Figure 2 is a schematic view showing the contact and ribs of the structure according to an embodiment of the application; Figure 1A

[0030] Figure 3 is a cross-sectional view of a detail of Figure 2 Figure 2

[0031] Figure 4 is a perspective view of a detail of the structure according to an embodiment of the application;

[0032] Figure 5 is a perspective view of a detail of the structure according to an embodiment of the application;

[0033] Figure 6 is a perspective view of a detail of the structure according to an embodiment of the application;

[0034] Figure 7 is a perspective view of a detail of the structure according to an embodiment of the application;

[0035] Figure 8 is a perspective view of a detail of the structure according to an embodiment of the application;

[0036] Figure 9 is a perspective view of a detail of the structure according to an embodiment of the application;

[0037] Figure 10 is an enlarged perspective view showing a detail of the protrusion of Figure 9

[0038] Figure 11 is a schematic side view of an anchoring element according to an embodiment of the application, around which a capillary adhesive flows by capillary action;

[0039] Figure 12 is a side schematic view of an empty space according to an embodiment of the application, into which a capillary adhesive flows as a capillary adhesive column by capillary action;

[0040] Figure 13 is a side schematic view of a capillary adhesive dispensed by a component according to an embodiment of the application;

[0041] Figure 14 is a side schematic view of a capillary adhesive dispensed by a substrate according to an embodiment of the application; and

[0042] Figure 15 is a flow chart showing a method of assembling a structure with controlled capillary coverage according to an embodiment of the application.

[0043] ​​​​The diagrams described herein are illustrative. Many variations are possible depending on the application described herein. For example, acts described can be performed in a different order from that described and other acts can be added, deleted or modified. Also, the term "coupled" and variations thereof describe having a communications path between two elements and does not imply a direct connection between the elements in which there are no intermediate elements / connections between them. All such variations are considered within the scope of the disclosure.

[0044] In the drawings and detailed description that follows, various elements of the drawings are designated with two or three digit reference numerals. Except where otherwise indicated, the left-most digit(s) of each reference numeral corresponds to the figure in which the element is first shown. DETAILED DESCRIPTION

[0045] Processor packages typically include a lid mounted on a laminate, a processor chip, discrete elements, where the bottom of the laminate typically includes a ball grid array (BGA) or a land grid array (LGA). The BGA or LGA provides electrical connections and communication with a printed circuit board (PCB).

[0046] For LGA and BGA applications, the laminate can also include a contact array that covers almost the entire bottom surface. These contacts are used to send and receive data and to power the processor chip. Thus, any holes through the laminate correspondingly remove or reduce the area that would otherwise be available for input / output (I / O) operations and / or power transfer and can be detrimental to the overall performance characteristics of the system. Thus, the pins that require the vias are sometimes considered less than ideal.

[0047] As an additional issue, for high speed electronic components, the dielectric properties of the material between adjacent electrical leads is typically critical to the overall performance characteristics of the system. While certain underfill (UF) materials are dielectric materials and do provide good dielectric properties, it is generally preferred to allow air to occupy the space between adjacent electrical leads for the highest quality to promote signal integrity. Thus, to pack as many components as possible into a surface mounted electrical component without sacrificing performance, it is generally desirable to minimize the area required for the adhesive or UF.

[0048] With the above in mind, it should be appreciated that side fill epoxies can be used to secure electrical components, but they require a substantial area outside of the device footprint for adhesive fillets.

[0049] Embodiments of the invention provide a structure for selectively underfilled electronic devices. The structure includes features that encourage capillary underfill to flow only in certain areas, thereby mechanically attaching the device to the underlying substrate without encapsulating the entire gap between the device and the substrate. The structure can have a controlled gap height (smaller gap height results in higher capillary pressure), specific local materials (underfill will preferentially flow under higher surface energy materials), and local roughening or activated surface features or mesh.

[0050] One or more embodiments of the invention address one or more of the above-mentioned shortcomings of the prior art by providing a structure in which the need for solder pins is eliminated, thereby allowing a higher signal density in a given component footprint. In addition, since capillary adhesive can be dispensed after solder wire bonding, it allows the components of the structure to self-center during reflow. Moreover, capillary adhesive can flow under the components, rather than side fill. This increases the area available for adhesive and reduces the distance between adjacent components due to the elimination of side fill flash.

[0051] Turning now to the drawings Figure 1A and 1B Structure 101 has controlled capillary coverage and includes a substrate 110, a central processing area 120, one or more components 130, and an adhesive 140. Substrate 110 can be formed from a laminate. Substrate 110 includes one or more first contacts (hereinafter "first contacts") 112 arranged in one or more groups along substrate 110. One or more components 130 are disposed about central processing area 120, and each component 130 includes a body 131, one or more second contacts (hereinafter "second contacts") 132 supported on body 131, and a rib 133 at a distance D (see Figure 2 and 3 ) from each second contact 132. Second contacts 132 can be provided as leads, electrical leads, balls (such as in a ball grid array), solder balls, pads, or the like. Rib 133 can be integrally connected or molded to body 131, a feature built onto body 131, a feature formed by removing material from body 131, or a feature made of a different material than body 131 and attached to body 131.

[0052] As shown in Figure 1A and 1B each component 130 is disposed proximate substrate 110 such that second contacts 132 of each component 130 are in communication with a corresponding portion of first contacts 112, and such that a corresponding surface portion of substrate 110 and rib 133 of each component 130 face each other with a controlled gap height H to define a fill space 150 (see Figure 1B). The adhesive 140 can be provided as one or more of a capillary adhesive, a glue, a low viscosity epoxy, and an underfill, and can be dispensed at one or more discrete points 141 (see Figure 1A ) for each component 130, whereby the adhesive 140 (hereinafter referred to as "capillary adhesive 140") is drawn by capillary action to fill the fill space 150. Once the capillary adhesive 140 cures, the capillary adhesive 140 mechanically attaches each component 130 to the substrate 110.

[0053] It should be appreciated that while each component 130 is illustrated as a leaded component, other embodiments exist. For example, each component 130 can be provided as a stacked silicon die or a leadless electrical component. However, for purposes of clarity and conciseness, the following description will refer to instances where each component is provided as a leaded component.

[0054] In instances where the capillary adhesive 140 is drawn by capillary action to fill the fill space 150 of each component 130, the final position of the capillary adhesive 140 corresponds to the position of the rib 133. Since the rib 133 is disposed at a distance D from each second contact 132 (and the first contact 112, by virtue of the corresponding arrangement of the first and second contacts 112, 132), the capillary adhesive 140 is maintained at a distance from the second and first contacts 132, 112. In these or other instances, air is provided around the second and first contacts 132, 112. The resulting dielectric properties of the structure 101 are improved.

[0055] It should be appreciated that the controlled gap height H, the fluid properties of the capillary adhesive 140, and the configuration of the rib 133 for each component 130 can be cooperatively determined, established, and / or set so as to establish a pressure of capillary action that drives the flow of the capillary adhesive 140. For example, a decrease in the controlled gap height H, with the capillary adhesive 140 unchanged, will result in an increase in the increase in the capillary pressure, and allow for a greater or increased length of the fill space 150.

[0056] The structure 101 can also include solder 160 (see Figure 1B ), by which each of the second contacts 132 is in electrical communication with a respective one of the first contacts 112. Reflow of the solder 160 can be performed prior to dispensing the capillary adhesive 140, such that each component 130 is effectively self-centered during the solder reflow process.

[0057] According to embodiments of the present invention, the components 130 can be positioned in close proximity to one another in the structure 101 (see Figure 1B). This is due to the components 130 being mechanically attached to the substrate 110 by the capillary adhesive 140 rather than by a side-filling adhesive that forms a side-filling bead or other similar feature. In the absence of such a filled bead, the components 130 can be directly adjacent to one another, thereby preserving surface area of the substrate 110 for use by other operational or functional elements.

[0058] Referring to Figure 2 and 3 , embodiments of a given component 130 of the present application are shown. As shown in Figure 2 , the component 130 has an H-shaped configuration in which the rib 133 has a central member 201 and opposing end members 202 and second contacts 132 arranged in linear configurations 203 and 204 on either side of the central member 201 between the opposing end members 202 (as noted above, it is contemplated that the first contacts 112 will have a similar arrangement). Figure 3 As shown in , the second contacts 132 extend through and are supported by the body 131 to contact corresponding ones of the first contacts 112 on either side of the rib 133. The capillary adhesive 140 occupies the fill space 150 between the rib 133 and the substrate 110 but does not contact the second contacts 132 or the first contacts 112.

[0059] Referring to Figures 4-8 , according to embodiments of the present application, the rib 133 of each component 130 can have one or more of a rectangular, circular, and irregular geometry, and can include one or more of a chamfered, discontinuous, tapered, and stepped portion. For example, as shown in Figure 4 (and Figure 2 ), the rib 133 of the component 130 can have an H-shaped configuration 401. Although not shown, according to alternative embodiments, the rib 133 can have a plus-shaped configuration, a circular or angular S-shaped configuration, a trapezoidal configuration, a short H-shaped configuration in which contacts are provided between and outside of the opposing end members, a U-shaped configuration, a U-shaped configuration with inwardly extending extensions, a bisecting configuration in which members extend from a longitudinal member to bisect the contact structure, an enclosed configuration in which the contacts are fully or partially enclosed within one or more cavities defined by the rib, and a ring or circular configuration in which the contacts are arranged circumferentially around a radial member.

[0060] The following description of the rib 133 of a given component 130 will refer to the case in which the rib 133 has an H-shaped configuration 401 for purposes of clarity and simplicity, and it should be understood that the description applies to any configuration of the rib 133. Figure 4 As shown in

[0061] , the lower surface 410 of the rib 133 is substantially flat and planar. In contrast, as shown in Figure 4 , the upper surface 411 of the rib 133 is curved and convex.Figure 5 As shown, the lower surface 410 of the rib 133 has a chamfer 501. As Figure 6 shown, the lower surface 410 of the chamfer of the rib 133 is discontinuous and forms an interruption 601, while Figure 7 and Figure 8 the lower surface 410 of the chamfer of the rib 133 is provided with a taper 701 (see Figure 7 ) and a step structure 801 (see Figure 8 ). In each case, the structure of the rib 133 is an important factor in the ability to create capillary pressure and capillary adhesive 140 to fill the respective fill space 150. In particular, it is noted that Figure 5 the chamfer 501 reduces the surface area that the capillary adhesive 140 contacts and allows a given amount of capillary adhesive 140 to extend further along the length of the fill space 150. On the other hand, Figure 6 , 7 and 8, the interruption 601, the taper 701, and the step structure each tend to reduce or stop the ability of the capillary adhesive 140 to continue to flow by capillary action, and in these or other cases, two or more discrete dots 141 can be required to achieve full capillary coverage.

[0062] With reference to Figure 9 and 10 , in accordance with embodiments of the present application, the rib 133 for a given component 130 can include a hard stop element 901. The hard stop elements 901 each have a hard stop height that establishes a lower limit for the controlled gap height H of the respective fill space 150. That is, while at the beginning of the solder reflow process, the assembly 130 can be disposed at an initial height above the substrate 110 to connect the second contacts 132 with the first contacts 112, and can migrate downward toward the substrate 110 as the solder reflow process continues, the hard stop elements 901 can eventually come into contact with the substrate 110 to prevent further migration of the assembly 130. It will be appreciated that the hard stop height of each of the hard stop elements 901 will be set at or near a height whereby the pressure of capillary action is sufficient to cause a selected capillary adhesive 140 to flow through the entire fill space 150.

[0063] With reference to Figure 11 and 12 , the rib 133 of a given component 130 can include an anchoring element 1101 that extends partially across the controlled gap height H (see Figure 11 ) and / or the rib 133 of a given component 130 can be formed to define an open portion 1201 into which a column of capillary adhesive 140 is drawn by capillary action (see Figure 12 ). In these or other cases, the anchoring element 1101 and the open portion 1201 serve to lift and promote a particular flow pattern of the capillary adhesive 140.

[0064] Referring back to FIG. 1 and Figures 4-8 , the discrete point 141 for a given component 130 can be defined in or adjacent to the fill space 150. In the former case, as Figures 4-8 illustrated, the capillary adhesive 140 is drawn from the discrete point 141 to fill the remainder of the fill space 150 by capillary action. In the latter case, as illustrated in FIG. 1, the capillary adhesive 140 is drawn to fill the entire fill space 150 by capillary action.

[0065] Referring to Figure 13 and 14 , the capillary adhesive 140 can be dispensed through the component 130 or the substrate 110. That is, as Figure 13 illustrated, the capillary adhesive 140 can be dispensed through a via 1301 defined through the body 131 of the component 130 and toward the substrate 110. Alternatively, as Figure 14 illustrated, the capillary adhesive 140 can be dispensed through a via 1401 defined through the substrate 110 and toward the component 130. In these or other cases, the discrete point 141 can (but need not) be defined in the fill space 150.

[0066] Referring to Figure 15 , a method of assembling a structure 101 having controlled capillary coverage is provided. As Figure 15 illustrated, the method includes disposing the element 130 such that the second contact 132 is positioned to communicate with the first contact 112 and the rib 133 faces the surface (1501) of the substrate 110. The method further includes soldering the second contact 132 to the first contact 112 such that the rib 133 faces the surface of the substrate 110 at a controlled gap height H to define the fill space 150 (1502), and dispensing the capillary adhesive 140 at the discrete point 141 to draw the capillary adhesive 140 to fill the fill space 150 by capillary action (1503). The method can further include disposing a hard stop element between the rib 133 and the surface of the substrate 110 during the soldering of operation 1502 such that the rib 133 faces the surface of the substrate 110 at the controlled gap height H, which is effectively established by the hard stop element to define the fill space 150.

[0067] Various embodiments of the present application are described herein with reference to the accompanying drawings. Alternative embodiments of the application can be devised without departing from the scope of the present application. Various connections and positional relationships (e.g., over, below, adjacent, etc.) are set forth in the following description and drawings. These various connections and / or positional relationships, unless otherwise stated, can be direct or indirect, and the present application is not intended to be limiting in this respect. Thus, a coupling can be direct or indirect and the positioning of entities can be direct or indirect positioning. In addition, various tasks and process steps described herein can be incorporated in more comprehensive programs, procedures, or processes having additional steps or functionality not described in detail herein.

[0068] One or more methods described herein can be implemented in any of the following technologies, or their combination, which are or will be known in the art: discrete logic circuitry having logic gates for implementing logic functions upon an application of data signals, application specific integrated circuits (ASICs) having appropriate combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), and the like.

[0069] For the sake of brevity, conventional techniques related to making and using aspects of the application can or can not be described in detail herein. In particular, various aspects of computing systems and specific computer programs to implement the various technical features described herein are well known. Accordingly, in the interest of brevity, many conventional implementation details are only mentioned briefly herein or are omitted entirely without providing the well-known system and / or process details.

[0070] In some embodiments, various functions or acts can be performed in a given position and / or in connection with the operation of one or more apparatuses or systems. In some embodiments, a portion of a given function or act can be performed in a first device or position and another portion of the same function or act can be performed in one or more additional devices or positions.

[0071] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0072] All means or step plus function elements in the claims that follow the expression “comprising” are intended to be construed in the manner set forth in 35 U.S.C. § 112(f) unless otherwise indicated. Embodiments are presented in the context of specific examples to provide a person of ordinary skill in the art with an enabling description of various embodiments of the application, and the best way to make and use them, but are not intended to represent one or more specific embodiments of the application, and should not be construed as such. The embodiments are presented for illustrative purposes and description, but are not intended to be exhaustive or to be limited to the forms disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the application. Embodiments are chosen and described in order to best explain the principles of the application and its best mode of operation, and to enable others skilled in the art to understand various embodiments of the application with various modifications as are suited to the particular use contemplated, as well as to enable the practice of the application.

[0073] The figures described herein are illustrative. Numerous variations are possible for the figures or steps (or operations) described herein without departing from the scope of the application. For example, the acts can be performed in a different order from those described herein, or additional, fewer, or different acts can be performed. Further, the term “coupled” describes having a signal pathway between two elements and does not mean a direct connection between the elements with no intermediate elements / connections therebetween. All such variations are considered to be part of the application.

[0074] The following definitions and abbreviations are used in the claims and specification. As used herein, the terms “comprises,” “comprising,” “includes,” “including,” “has,” “having,” “contains,” “containing,” “wherein,” “where,” “based on,” “in which,” “whereby,” or variations thereof do not include a sole recitation of a process, a composition, a method, a product, or a structure, but rather are intended to mean that the process, composition, method, product, or structure is an element that is encompassed by the claim or specification. For example, a composition, a mixture, a process, a method, an article, or an apparatus that comprises a list of elements is not necessarily limited to those elements but can include other elements not expressly listed or inherent to such composition, mixture, process, method, article, or apparatus.

[0075] Additionally, the term “exemplary” is used herein to mean “serving as an example, instance, or illustration.” Any embodiment or design described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other embodiments or designs. The terms “at least one” and “one or more” are understood to include any integer greater than or equal to one, i.e., one, two, three, four, etc. The term “a plurality” is understood to include any integer greater than or equal to two, i.e., two, three, four, five, etc. The term “connection” can include both an indirect “connection” and a direct “connection.”

[0076] The terms “about,” “substantially,” “approximately,” and variations thereof, are intended to include amounts that are close to the stated amount, but can not be exactly equal to the stated amount. For example, “about” can include an amount that is ± 8% or 5% or 2% of a given value.

[0077] The present application can be a system, a method, and / or a computer program product at any possible technical detail level of integration. The computer program product can include a computer readable storage medium (or media) having computer readable program instructions thereon for causing a processor to carry out aspects of the present application.

[0078] The computer readable storage medium can be a tangible device that can retain and store instructions for use by an instruction execution device. The computer readable storage medium can be, for example, but is not limited to, an electronic storage device, a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted via a wire cable. Computer readable program instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer readable program instructions from the network and forwards the computer readable program instructions to a computer readable storage medium within the respective computing / processing device for storage and / or execution. Computer readable program instructions for carrying out aspects of the present application can be any desirable set of instructions to be executed on a computer or processing device. The computer readable program instructions may

[0079] The computer readable program instructions described herein can be downloaded to respective computing / processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and / or a wireless network. The network can comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers and / or edge servers. A network adapter card or network interface in each computing / processing device receives computer readable program instructions from the network and forwards the computer readable program instructions to a computer readable storage medium within the respective computing / processing device for storage and / or execution. Computer readable program instructions for carrying out aspects of the present application can be any desirable set of instructions to be executed on a computer or processing device. The computer readable program instructions may

[0080] Computer readable program instructions for carrying out operations of the present application can be assembly instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, configuration data for an integrated circuit, or source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++ or the like, and a procedural programming language such as the "C" programming language or similar programming languages. The computer readable program instructions can execute entirely on the user's computer, partly on the user's computer, as a stand-alone software package, partly on the user's computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection can be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGA), or programmable logic arrays (PLA) can execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present application.

[0081] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process such that the instructions which execute on the computer, other programmable apparatus, or other device implement the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0082] These computer readable program instructions can be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions / acts specified in the flowchart and / or block diagram block or blocks. These computer readable program instructions can also be stored in a computer readable storage medium that can direct a computer, a programmable data processing apparatus, and / or other devices to function in a particular manner, such that the computer readable storage medium having instructions stored therein comprises an article of manufacture including

[0083] The computer readable program instructions can also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process such that the instructions which execute on the computer, other programmable apparatus, or other device implement the functions / acts specified in the flowchart and / or block diagram block or blocks.

[0084] The computer program product of the present application can be implemented on one computer or on a plurality of computers in or coupled to the system. The computer program code can be written in any combination of one or more computer languages, including one or more of Java, C++, Python, C, and / or Verilog, among others. The computer program code can be divided into one or more software modules or engines, each of which can include one or more instructions for implementing the specified logic function(s) of the module or engine. These software modules or engines can be executed by one or more general-purpose computers, special-purpose computers, or other programmable apparatuses, such as network elements, to produce machines that act on (i.e., process) input data to generate desired output data. The computer program code can also be implemented in discrete hardware that is functionally coupled to the system, or in a combination of one or more software modules and one or more hardware functions.

[0085] The description of the various embodiments of the present application has been presented for purposes of illustration, but is not intended to be exhaustive or limited to the embodiments disclosed. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope of the described embodiments. The terminology used herein was chosen to best explain the principles of the embodiments, the practical application, or technical improvement over technology found in the marketplace, or to enable others skilled in the art to understand the embodiments being described herein.

[0086] In a preferred embodiment of the application described herein, there is provided a structure with controlled capillary coverage comprising: a substrate comprising one or more first contacts; a first component and a second component, each comprising one or more second contacts and a rib disposed at a distance from each of the one or more second contacts, each of the first component and the second component being disposed immediately adjacent to each other such that: the respective one or more second contacts are in communication with a respective portion of the one or more first contacts, and a respective corresponding surface of the substrate and the respective rib face each other with a controlled gap height to define a first fill space and a second fill space; and one or more of a capillary adhesive, a glue, an epoxy, and a underfill dispensed at first and second discrete points, whereby the one or more of a capillary adhesive, a glue, an epoxy, and a underfill is drawn by capillary action to fill the first and second fill spaces, respectively.

[0087] In a preferred embodiment of the application described herein, a method of assembling a structure with controlled capillary coverage is provided, the method comprising: providing a component such that one or more contacts thereof are positioned in communication with one or more contacts of a substrate, and a rib of the component faces a surface of the substrate; welding the one or more contacts of the component to the one or more contacts of the substrate; providing a hard stop element between the rib and the surface during welding such that the rib faces the surface with a controlled gap height established by the hard stop element to define a fill space; and dispensing one or more of a capillary adhesive, a glue, an epoxy, and a underfill at discrete points, whereby the one or more of a capillary adhesive, a glue, an epoxy, and a underfill are drawn by capillary action to fill the fill space.

Claims

1. A structure with controlled capillary coverage, the structure comprising: a substrate comprising one or more first contacts; a component comprising one or more second contacts and a rib arranged at a distance from each of the one or more second contacts, the component arranged such that the one or more second contacts are in communication with the one or more first contacts and the rib and a corresponding surface of the substrate face each other with a controlled gap height to define a fill space; and an adhesive dispensed at discrete points, whereby the adhesive is drawn by capillary action to fill the fill space, wherein the rib comprises a hard stop element.

2. The structure of claim 1, wherein the adhesive comprises one or more of a capillary adhesive, a glue, an epoxy, and a underfill.

3. The structure of claim 1, further comprising a solder, each of the one or more second contacts in electrical communication with a corresponding one of the one or more first contacts through the solder.

4. The structure of claim 1, wherein the controlled gap height, fluid properties of the adhesive, and configuration of the rib establish a pressure of the capillary action.

5. The structure of claim 1, wherein the rib comprises one or more of a chamfer, a discontinuity, a tapered portion, and a stepped portion.

6. The structure of claim 1, wherein at least one of: the rib comprises an anchoring element that extends partially across the controlled gap height, and the rib defines an open portion into which a column of the adhesive is drawn by capillary action.

7. The structure of claim 1, wherein: the discrete points are located in the fill space and the adhesive is drawn by the capillary action to fill a remaining portion of the fill space, or the discrete points are adjacent to the fill space and the adhesive is drawn by the capillary action to fill the entire fill space.

8. The structure of claim 1, wherein the adhesive is dispensed through a via defined by the component or the adhesive is dispensed through a via defined by the substrate.

9. A method of assembling a structure with controlled capillary coverage, the method comprising: positioning a component such that one or more contacts thereof are positioned to be in communication with one or more contacts of a substrate and a rib of the component faces a surface of the substrate, the rib comprising a hard stop element; soldering the one or more contacts of the component to the one or more contacts of the substrate such that the rib faces the surface with a controlled gap height defined by the hard stop element to define a fill space; and dispensing one or more of a capillary adhesive, a glue, an epoxy, and an underfill at discrete points, whereby one or more of the capillary adhesive, the glue, the epoxy, and the underfill are drawn by capillary action to fill the fill space. ​ ​ 10. The method of claim 9, further comprising setting the controlled gap height, selecting the one or more of the capillary adhesive, the glue, the epoxy, and the underfill for fluidic properties, and configuring the rib to establish the capillary pressure.

11. The method of claim 9, wherein: the discrete point is located in the fill space, and one or more of the capillary adhesive, the glue, the epoxy, and the underfill is drawn to fill a remainder of the fill space by the capillary action, or the discrete point is adjacent to the fill space, and one or more of the capillary adhesive, the glue, the epoxy, and the underfill is drawn to fill the entire fill space by the capillary action.

12. The method of claim 9, wherein: the dispensing of one or more of the capillary adhesive, the glue, the epoxy, and the underfill includes dispensing through a via defined by the component, or the dispensing of the one or more of the capillary adhesive, the glue, the epoxy, and the underfill includes dispensing through a via defined by the substrate.

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