PATENT DOCUMENT

Publication Number: US-9374898-B2
Application Number: US-201313869881-A
Country: US
Kind Code: B2

Title: Electrical and mechanical interconnection for electronic components

Abstract:
The described embodiments relate generally to electronic devices and more particularly to methods for forming mechanical and electrical connections between components within an electronic device. In one embodiment, an interconnect component such as a flex cable is attached to a substrate such as a printed circuit board. A plurality of apertures can be created in the interconnect component, passing through bonding pads located on one end of the interconnect component. The interconnect component can then be aligned with bonding pads on the substrate with the bonding pads on the interconnect component facing away from the substrate. A conductive compound can be injected into the apertures through the interconnect component, forming a mechanical and electrical connection between the bonding pads. In some embodiments, an adhesive layer can be used to further strengthen the bond between the interconnect component and the substrate.

Claims:
What is claimed is: 
     
       1. A method for providing an electrical and mechanical connection between a substrate and an interconnect component, the method comprising:
 disposing a first conductive bonding pad over a first surface of the interconnect component; 
 forming a first aperture that extends through the first conductive bonding pad; 
 forming a second aperture through the interconnect component, the second aperture aligned with the first aperture and extending from the first surface to a second surface of the interconnect component opposite the first surface, wherein the second surface comprises a planar surface; 
 engaging the second surface with a second conductive bonding pad disposed on the substrate; and 
 depositing a conductive compound into the first aperture and the second aperture, wherein depositing the conductive compound mechanically and electrically couples the first conductive bonding pad to the second conductive bonding pad, and wherein the electrical and mechanical connection between the substrate and the interconnect component is defined by a combined thickness of the interconnect component, the conductive compound, the substrate, the first conductive bonding pad, and the second conductive bonding pad. 
 
     
     
       2. The method as recited in  claim 1 , further comprising:
 prior to placing the second surface of the interconnect component in contact with the surface of the substrate, applying an adhesive layer between the interconnect component and the substrate, the adhesive layer having an opening aligned with the second aperture, wherein the combined thickness of the interconnect component, the conductive compound, the substrate, the first conductive bonding pad, and the second conductive bonding pad, and the adhesive layer. 
 
     
     
       3. The method as recited in  claim 2 , wherein the adhesive layer comprises an anisotropic conductive film. 
     
     
       4. The method as recited in  claim 1 , further comprising plating an interior surface of the first aperture an and interior surface of the second aperture prior to depositing the conductive compound. 
     
     
       5. A non-transient computer readable medium for storing computer code executable by a processor in a computer aided manufacturing system for mechanically and electrically coupling an interconnect component to a substrate, the non-transient computer readable medium comprising:
 computer code for creating a plurality of apertures in the interconnect component, wherein the plurality of apertures pass at least partially through a plurality of conductive bonding pads located on a first surface of the interconnect component; 
 computer code for adhesively securing a second surface of the interconnect component opposite the first surface with a surface of the substrate, by an adhesive layer that engages the second surface and the surface of the substrate; 
 computer code for aligning the interconnect component so that the plurality of conductive bonding pads located in the first surface of the interconnect component are positioned above a plurality of corresponding bonding pads located on the surface of the substrate; and 
 computer code for depositing a conductive compound along an outer surface of each of the plurality of conductive bonding pads located on the interconnect component, wherein the conductive compound is allowed to fill each of the plurality of apertures in the interconnect component, mechanically and electrically coupling the plurality of bonding pads located on the interconnect component to the plurality of corresponding bonding pads located on the substrate, and wherein the interconnect component maintains a uniform thickness from the first surface to the second surface. 
 
     
     
       6. The non-transient computer readable medium as recited in  claim 5 , further comprising:
 computer code for receiving data from one or more sensors capable of sensing a position of the substrate and the interconnect component; and 
 computer code for using the position of the substrate and the interconnect component to control positioning features configured to align the substrate with the interconnect component. 
 
     
     
       7. The non-transient computer readable medium as recited in  claim 6 , further comprising computer code for controlling a heating element embedded in a fixture holding the substrate, wherein the heating element provides heat necessary to cure the conductive compound. 
     
     
       8. The non-transient computer readable medium as recited in  claim 7 , further comprising computer code for rotating an upper fixture holding the interconnect component into a lower fixture holding the substrate after the interconnect component and the substrate are aligned. 
     
     
       9. The method as recited in  claim 1 , wherein the substrate is a printed circuit board. 
     
     
       10. The method as recited  claim 1 , wherein the substrate is a glass layer functioning as a display for an electronic device. 
     
     
       11. The method as recited in  claim 1 , wherein creating the second aperture comprises creating the second aperture in a flex cable. 
     
     
       12. The method as recited in  claim 1 , further comprising depositing the conductive compound along an outer surface of the first conductive bonding pad. 
     
     
       13. The method as recited in  claim 12 , wherein depositing the conductive compound along the outer surface of the first conductive bonding pad comprises depositing solder. 
     
     
       14. The method as recited in  claim 1 , wherein creating the second aperture comprises creating a notch disposed along a periphery of the first conductive bonding pad. 
     
     
       15. The method as recited in  claim 1 , wherein the first aperture is formed along an edge of the first conductive bond pad to define a notch. 
     
     
       16. The method as recited in  claim 1 , wherein a diameter second aperture varies from the first surface of the interconnect component to the second surface of the interconnect component. 
     
     
       17. The method as recited in  claim 16 , wherein the diameter gradually increases from the first surface to the second surface. 
     
     
       18. The method as recited in  claim 1 , wherein the second conductive bonding pad comprises openings that include an adhesive disposed in the openings.

Description:
FIELD OF THE DESCRIBED EMBODIMENTS 
     The described embodiments relate generally to electronic devices and more particularly to methods for forming mechanical and electrical connections between components within an electronic device. 
     BACKGROUND 
     Electronic devices can contain a number of electronic components that are electrically and mechanically coupled to one another. For example, many devices employing integrated displays or touch sensitive displays include means for electrically connecting traces on a glass layer to a flex cable that can carry signals from a printed circuit board (PCB). In other designs, a PCB or other component including circuitry can be coupled directly to the glass layer. Due to the shrinking size of many electronic devices, design constraints often drive these connections to be as small as possible. At the same time, many electronic devices are subject to large shock loads and must include connections that are robust enough to allow the device to function reliably over an extended period of time. 
     One method of forming a connection involves the use of a conductive adhesive layer. Conductive particles can be embedded in a resin or adhesive compound and applied to a base substrate using lamination or printing processes. Anisotropic conductive film (ACF) is commonly used as an adhesive layer. Adhesives such as ACF are capable of achieving a very fine pitch, or distance between adjacent conductors. However, ACF is relatively weak when compared to other bonding methods and can create reliability issues when the connection undergoes stress. Another method involves the use of solder or other conductive pastes such as anisotropic conductive paste (ACP). Conductive pastes can provide a mechanical connection stronger than that of conductive films such as ACF. However, conductive pastes are not capable of achieving the same pitch as adhesives. In some cases, conductive pastes and solder can require a separation between conductors that is 5-10 times greater than that of adhesives. 
     Therefore, what is desired is a method for mechanically and electrically coupling two electronic components that provides a robust mechanical connection similar to ACP and solder while maintaining a fine pitch similar to ACF. 
     SUMMARY OF THE DESCRIBED EMBODIMENTS 
     This paper describes various embodiments that relate to methods for providing an electrical and mechanical connection between a substrate and an interconnect component. In one embodiment, a process for forming a connection is described. The process includes at least the following steps: (1) creating a plurality of apertures in the interconnect component and allowing the apertures to pass at least partially through a plurality of conductive bonding pads located on a first surface of the interconnect component, (2) placing a second surface of the interconnect component opposite the first surface in contact with a surface of the substrate, (3) aligning the interconnect component so that the plurality of conductive bonding pads located on the first surface of the interconnect component are positioned above a plurality of corresponding bonding pads located on the surface of the substrate, and (4) depositing a conductive compound along an outer surface of each of the conductive bonding pads located on the interconnect component. The conductive compound is allowed to fill each of the apertures in the interconnect component, mechanically and electrically coupling the bonding pads located on the interconnect component to the bonding pads located on the substrate. 
     In another embodiment, an electronic device is described. The electronic device includes a substrate overlaid with circuitry and a series of bonding pads. The electronic device also includes an interconnect component having a first surface and a second surface with a series of bonding pads located on the first surface. The second surface of the interconnect component is positioned adjacent to the surface of the substrate and the bonding pads on the substrate are aligned with the bonding pads on the first surface of the interconnect component. A number of apertures are also included in the interconnect component. The apertures pass at least partially through the conductive bonding pads located on a first surface of the interconnect compound. Finally, a conductive compound is disposed within the apertures. The conductive compound mechanically and electrically couples the interconnect component to the substrate. 
     In yet another embodiment, a system for mechanically and electrically coupling an interconnect component to a substrate is described. The system includes a lower fixture configured to support the substrate and including one or more positioning features capable of moving the substrate into a pre-defined position. In addition, an upper fixture is included and configured to support the interconnect component. The upper fixture can be rotatably coupled to the lower fixture and can also include one or more positioning features capable of moving the interconnect component into a pre-defined position. The system also includes a nozzle configured to deposit a conductive compound through a plurality of apertures that are included in the interconnect component. Finally, the system includes a controller capable of automatically aligning the interconnect component and the substrate and controlling the position and flow rate of the nozzle. In some embodiments, the upper fixture can rotate relative to the lower fixture after the interconnect component and substrate are aligned, allowing the nozzle access to the apertures on the interconnect component. 
     In still another embodiment, a non-transient computer readable medium for storing computer code executable by a processor in a computer aided manufacturing system for mechanically and electrically coupling an interconnect component to a substrate is described. The non-transient computer readable medium includes at least the following: (1) computer code for creating a plurality of apertures in the interconnect component and allowing the apertures to pass at least partially through a plurality of conductive bonding pads located on a first surface of the interconnect component, (2) computer code for placing a second surface of the interconnect component opposite the first surface in contact with a surface of the substrate, (3) computer code for aligning the interconnect component so that the plurality of conductive bonding pads located on the first surface of the interconnect component are positioned above a plurality of corresponding bonding pads located on the surface of the substrate, and (4) computer code for depositing a conductive compound along an outer surface of each of the plurality of conductive bonding pads located on the interconnect component. The conductive compound is allowed to fill each of the plurality of apertures in the interconnect component, mechanically and electrically coupling the plurality of bonding pads located on the interconnect component to the plurality of bonding pads located on the substrate. 
     Other aspects and advantages of the invention will become apparent from the following detailed description taken in conjunction with the accompanying drawings which illustrate, by way of example, the principles of the described embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The described embodiments may be better understood by reference to the following description and the accompanying drawings. Additionally, advantages of the described embodiments may be better understood by reference to the following description and accompanying drawings. These drawings do not limit any changes in form and detail that may be made to the described embodiments. Any such changes do not depart from the spirit and scope of the described embodiments. 
         FIG. 1A  shows a prior art connection between a substrate and an interconnect component. 
         FIG. 1B  shows a cross-sectional view of a prior art anisotropic conductive film (ACF) process. 
         FIG. 1C  shows a cross-sectional view of a prior art conductive paste or soldering process. 
         FIG. 2A  shows a plan view of an interconnect component coupled to a substrate. 
         FIG. 2B  shows a cross-sectional view of an interconnect component coupled to a substrate. 
         FIG. 3A  shows an interconnect component with circular apertures. 
         FIG. 3B  shows an interconnect component with square apertures. 
         FIG. 3C  shows an interconnect component with a single aperture. 
         FIG. 3D  shows an interconnect component with rectangular notches disposed along the sides of the conductive pads. 
         FIG. 3E  shows an interconnect component with notches disposed along the sides of the conductive pads. 
         FIG. 3F  shows an interconnect component with notches disposed at the ends of the conductive pads. 
         FIG. 4A  shows a cross-sectional view of an interconnect component coupled to a substrate using an adhesive layer. 
         FIG. 4B  shows a plan view of an interconnect component coupled to a substrate using an adhesive layer. 
         FIG. 4C  shows a cross-sectional view of an interconnect component coupled to a substrate using an adhesive layer. 
         FIG. 5A  shows a cross-sectional view of an interconnect component containing apertures with varying shape. 
         FIG. 5B  shows a cross-sectional view of an interconnect component containing apertures with varying shape. 
         FIG. 6  shows a cross sectional view of an interconnect component with plated apertures. 
         FIG. 7  shows a plan view of an interconnect component coupled to a substrate using an adhesive layer and a notch. 
         FIG. 8A  shows a system for aligning and coupling an interconnect component to a substrate. 
         FIG. 8B  shows a system for aligning and coupling an interconnect component to a substrate in a closed position. 
         FIG. 9  shows a flow chart describing a process for coupling an interconnect component and a substrate. 
         FIG. 10  shows a block diagram of an electronic controller capable of controlling the manufacturing process. 
     
    
    
     DETAILED DESCRIPTION OF SELECTED EMBODIMENTS 
     Representative applications of methods and apparatus according to the present application are described in this section. These examples are being provided solely to add context and aid in the understanding of the described embodiments. It will thus be apparent to one skilled in the art that the described embodiments may be practiced without some or all of these specific details. In other instances, well known process steps have not been described in detail in order to avoid unnecessarily obscuring the described embodiments. Other applications are possible, such that the following examples should not be taken as limiting. 
     In the following detailed description, references are made to the accompanying drawings, which form a part of the description and in which are shown, by way of illustration, specific embodiments in accordance with the described embodiments. Although these embodiments are described in sufficient detail to enable one skilled in the art to practice the described embodiments, it is understood that these examples are not limiting; such that other embodiments may be used, and changes may be made without departing from the spirit and scope of the described embodiments. 
     Several methods are described for forming a mechanical and electrical connection between conductive bonding pads on a substrate and an interconnect component. Apertures can be created in the interconnect component that provide an opening through bonding pads on the interconnect component and any structure the bonding pads are attached to. The interconnect component can then be placed over the substrate with the interconnect component bonding pads facing away from the substrate. Once the bonding pads are aligned, a conductive paste or solder can be injected into the apertures, forming a mechanical and electrical connection between the boding pads on the interconnect component and corresponding bonding pads on the substrate. In some embodiments, a non-conductive adhesive can also be used to improve the mechanical connection between the interconnect component and the substrate. In addition, various methods for forming the apertures and injecting conductive materials into the apertures are disclosed. 
       FIG. 1A  shows a prior art assembly demonstrating how an interconnect component such as flex cable  104  can be attached to substrate  102  using conventional methods. Bonding pads  106  can be arranged on a lower surface of flex cable  104 , facing substrate  102 . Similarly, bonding pads  108  can be arranged on an upper surface of substrate  102  and aligned with bonding pads  106 . Substrate  102  can represent a printed circuit board, glass substrate, flexible substrate, or any other surface on which circuitry can be overlaid in an electronic device. In addition, flex cable  104  can be replaced by several other components, including another rigid substrate, rigid flex, or any other interconnect component including bonding pads. 
       FIG. 1B  shows a cross-sectional view of assembly  100  demonstrating a prior art method for mechanically and electrically coupling substrate  102  and flex cable  104  using anisotropic conductive film (ACF) or any similar conductive adhesive. Bonding pads  106  on flex cable  104  can be aligned downwards to face bonding pads  108 . Then, conductive film  110  can be deposited on either bonding pads  106  or bonding pads  108 . Once conductive film  110  is in place, bonding pads  106  on flex cable  104  can be adhered to bonding pads  108  on substrate  102  by aligning the bonding pads and applying pressure. In some cases, heat can also be applied to properly cure conductive film  110 . The resulting bond can achieve a high density pitch (spacing between adjacent conductive pads) but can produce a relatively weak bond that can compromise the reliability of the connection. 
       FIG. 1C  shows a cross-sectional view of an alternative assembly  100  demonstrating another prior art method for coupling substrate  102  and flex cable  104  using conductive paste or solder. Conductive paste  112  can be applied to either bonding pads  106  on flex cable  104  or bonding pads  108  on substrate  102 . Then, corresponding bonding pads on substrate  102  and flex cable  104  an be place in contact with one another and heat can be applied, causing conductive paste  112  to melt and reform, creating an electrical and mechanical bond between bonding pads  106  and  108 . The resulting mechanical bond can be relatively strong. However, the use of conductive paste or solder cannot achieve the fine pitch that is available with conductive film. As a result, the bonding area must take up greater room on substrate  102 . 
       FIG. 2A  shows assembly  200 , demonstrating a method for creating a connection that can provide a strong mechanical connection similar to that available using conductive paste and solder while maintaining a fine pitch that is commonly available only when using conductive films such as ACF. Substrate  102  can represent any component within an electrical device that is overlaid with circuitry and includes bonding pads for electrically and mechanically connecting to an interconnect component or other electronic component. In some embodiments, substrate  102  can represent a printed circuit board (PCB). In other embodiments, substrate  102  can represent a glass substrate overlaid with circuitry such as a thin film transistor glass layer in an LCD display or a capacitive glass layer in a touch screen assembly. In other embodiments, substrate  102  can represent a flexible structure such as rigid flex or any other technically feasible surface on which circuitry can be overlaid in an electronic device. A number of bonding pads  108  can be provided on a surface of substrate  102  and electrically coupled to circuitry overlaid on substrate  102 . 
     Interconnect component  202  can be positioned adjacent to substrate  102  and can be electrically and mechanically coupled to substrate  102  and bonding pads  108 . As pictured, interconnect component  202  represents a flex cable. However, the disclosed method can be used with a variety of interconnect components. In other embodiments, interconnect component  202  can represent a PCB, glass layer, rigid flex assembly, or any other technically feasible component including circuitry and bonding pads. Interconnect component  202  can include a number of bonding pads  204  oriented away from substrate  102 . Bonding pads  204  can be electrically coupled to traces within interconnect component  202  that carry electrical signals between substrate  102  and another electronic component. Furthermore, bonding pads  204  can be formed from a metallic conductor such as copper or any other suitably rigid conductive material. A number of apertures  206  can be provided in each of bonding pads  204 . Apertures  206  can represent an opening that passes through bonding pad  204  and interconnect component  202 , provide access to bonding pads  108  on substrate  102 . Various shapes and configurations of apertures  206  are discussed below in  FIGS. 3A-3F . 
       FIG. 2B  shows cross-sectional view A-A taken from  FIG. 2A  and demonstrates the process by which interconnect component  202  can be electrically and mechanically bonded to substrate  102  using apertures  206 . Substrate  102  is positioned with bonding pads  108  facing upwards and interconnect component  202  is placed in contact with bonding pads  108  with bonding pads  204  also facing upwards. Then, nozzle  210  can deposit conductive compound  208  along an upper surface of bonding pad  204  and into apertures  206 . Once conductive compound  208  is deposited, a robust mechanical and electrical connection is formed between bonding pads  108  and bonding pads  204 . Conductive compound  208  can represent a variety of different compounds, including anisotropic conductive paste (ACP), solder, silver ink, Ag materials, or any other technically feasible compound capable of forming an electrical connection between bonding pads  108  and  204 . In addition, conductive compound  208  can be applied using a variety of methods including printing processes, jetting processes, thermal sintering processes, and any other technically feasible means of precisely applying conductive compound  208  to assembly  200 . 
       FIGS. 3A-3F  show various embodiments of interconnect component  300  utilizing different types of apertures. As is described below, the type of aperture chosen can depend on the design requirements and limitations of a particular application. In  FIG. 3A , a number of circular apertures  302  are provided. Circular apertures  302  can be preferable when a process such as drilling is used to create the apertures. However, a variety of different shaped apertures can be used. For example,  FIG. 3B  shows a series of square apertures  304 . In addition to squares, any other suitable shape can be used to create apertures  304 . Furthermore, the size of apertures  304  can vary. In applications involving devices that are subject to significant shock loads, apertures with additional area can be helpful in providing additional bonding area for conductive compound  208 . In some embodiments, it can be preferable to include apertures  304  that cover approximately 25%-50% of bonding pads  204 . However, aperture areas outside of this range can be used as well.  FIG. 3C  shows an embodiment in which a single aperture  306  is positioned in each of bonding pads  204 . As shown, apertures  306  have a rectangular shape. However, any other suitable shape can be used. A single aperture, such as aperture  306 , can be advantageous when a large bonding surface is desired between conductive compound  208  and bonding pad  108 . However, multiple apertures, such as those depicted in  FIGS. 3A and 3B  can provide additional redundancy to the connection. For example, if an electrical connection through one of apertures  302  fails, a signal can still be passed through other apertures  302  located on the same bonding pad  204 . 
     In some embodiments, notches can be provided along a periphery of each of bonding pads  204 .  FIGS. 3D-3F  show various embodiments employing such notches. In  FIG. 3D , rectangular notches are provided alongside sections of bonding pads  204  and in  FIG. 3E  semicircular notches are provided along a periphery of bonding pads  204 . While rectangular and semi-circular apertures are shown, any shape of notch suitable for allowing a conductive compound to pass through can be used.  FIG. 3F  shows another embodiment, in which bonding pads  204  are allowed to extend to an edge of interconnect component  202  and notches are placed along the edge. This embodiment can be useful when additional adhesives are used to bond interconnect component  202  to substrate  102  such as is described below in  FIG. 7 . Apertures  302 ,  304 ,  306 ,  308 ,  310 , and  312  can be created using various processes including drilling, laser cutting, etching, or any other technically feasible process for creating apertures. 
       FIG. 4 a    shows a cross-sectional view of assembly  400 , demonstrating how an additional adhesive layer  402  can increase the mechanical connection between substrate  102  and interconnect component  202 . Interconnect component  202  can be aligned and placed in contact with substrate  102  and conductive compound  208  can be deposited through apertures  206  and along an upper surface of bonding pad  204 , forming an electrical and mechanical connection between bonding pads  108  and  204 . In situations where additional mechanical adhesion is needed, adhesive layer  402  can be positioned between interconnect component  202  and substrate  102 . Adhesive layer  402  can represent an adhesive film, adhesive tape, epoxy resin, or any other suitable adhesive. In some embodiments, adhesive layer  402  can be applied to either interconnect component  202  or substrate  102  prior to bringing the two components in contact with one another. Adhesive layer  402  can be applied using a laminating process, printing process, manual application, or any other technically feasible means of depositing an adhesive layer. 
     In some embodiments, adhesive layer  402  can include openings configured to align with apertures  206  in interconnect component  202  so that conductive compound  208  can flow through adhesive layer  402  and reach bonding pads  108 . In other embodiments, adhesive layer  402  can be applied prior to creating apertures  206 , and openings in adhesive layer  402  can be created using the same process that creates apertures  206 . Adhesive layer  402  can also be applied between individual bonding pads  108  and  204  and directly onto interconnect component  202  and substrate  102 . This can provide additional adhesion between the two components. To prevent signals from cross from one bonding pad to another, adhesive layer  402  can be formed from a non-conductive material. However, in other embodiments, adhesive layer  402  can be limited to bonding pads  108  and can be formed from a conductive material such as ACF. This can provide additional paths for signals to transfer from conductive compound  208  to bonding pads  108 . 
       FIGS. 4B and 4C  show another embodiment in which adhesives are restricted to non-conductive areas of substrate  102  and interconnect component  202 .  FIG. 4B  shows a plan view of assembly  400 , including view B-B taken across interconnect component  202 .  FIG. 4C  shows cross-sectional view B-B, demonstrating how adhesive layer  404  is selectively applied to substrate  102 . Adhesive layer  404  can be limited to areas around and between bonding pads  108  only. By limiting adhesive layer  404  to non-conductive regions, the risk that adhesive layer  404  will interfere with the mechanical and electrical connection between conductive compound  208  and bonding pads  108  can be reduced. In some embodiments, the thickness of bonding pads  108  and adhesive layer  404  can be approximately equal to provide a flat surface for interconnect component  202  to interface with. Similar to adhesive layer  402  in  FIG. 4A , adhesive layer  404  can be formed from non-conductive materials including adhesive film, adhesive tape, epoxy resin, or any other suitable adhesive. Furthermore, adhesive layer  404  can be applied to either substrate  102  or interconnect component  202  prior to assembly. 
       FIGS. 5A and 5B  show cross-sectional views of assembly  500 , demonstrating how apertures  502  and  504  can vary as a function of depth. In some designs, additional surface area in regions where conductive compound  208  contacts bonding pads  108  can be advantageous for providing stronger mechanical and electrical bonds. For example, additional mechanical adhesion can be helpful in meeting design requirements when adhesives such as those described in  FIG. 4  are not used. When this is the case, the geometry of apertures  502  and  504  can vary as a function of depth to provide a larger contact area along a bottom surface of interconnect component  202  without removing an excessive amount of material from bonding pads  204  and interconnect component  202 . In  FIG. 5A , apertures  502  are formed in a truncated cone shape, providing a large surface area for bonding conductive compound  208  to bonding pads  108 . Alternatively, in  FIG. 5B , aperture  504  is shaped to have increased area at both upper and lower surfaces. This shape can be advantageous when additional area is needed along an upper surface of bonding pads  204  for directing conductive compound  208  into apertures  504  during the manufacturing process. In addition to the aperture shapes shown in  FIGS. 5A and 5B , any other suitable shape can be used according to specific design criteria. 
       FIG. 6  shows a cross-sectional view of assembly  600 , demonstrating how apertures  206  can be plated to increase conductivity between bonding pads  204  and bonding pads  108 . In some cases, a risk exists that a void or air bubble can form within openings  206 , preventing conductive compound  208  from forming an electrical connection between bonding pad  204  and bonding pad  108 . To alleviate this risk, side walls of apertures  206  can be plated with conductive material  602 . Conductive material  602  can be applied using conventional via plating techniques using any suitable conductive material such as copper. Assembly  600  is shown with adhesive layer  402  providing additional adhesion between interconnect component  202  and substrate  102 . However, plating techniques can be used when adhesive layer  402  is absent as well. 
       FIG. 7  shows a plan view of assembly  700 , demonstrating an alternative method for electrically and mechanically coupling substrate  102  to interconnect component  202 . Bonding pads  204  on interconnect component  202  can be posited along an edge of interconnect component  202  and notches  312  can be provided in bonding pads  204  along the edge. Additional detail of this configuration are shown above in  FIG. 3F . Bonding pads  702  can be coupled to substrate  102  and positioned so that a portion of bonding pads  702  are not covered by interconnect component  202 . Conductive compound  706  can then be applied within each of notches  312 , electrically coupling bonding pads  204  to bonding pads  702 . Conductive compound  706  can represent solder, silver ink, Ag materials, or any other technically feasible compound capable of forming an electrical connection between bonding pads  702  and  204 . Furthermore, conductive compound  706  can be applied using any of the above mentioned techniques, including printing, jetting, and manual application. To provide mechanical adhesion, adhesive layer  704  can be placed between interconnect component  202  and substrate  102  in a region outside of conductive compound  706 . Adhesive layer  704  can have properties similar to adhesive layer  402  described in  FIG. 4 . The combination of conductive compound  706  and adhesive layer  704  can provide a robust mechanical and electrical connection between substrate  102  and interconnect component  202 . 
       FIGS. 8A and 8B  show system  800  capable of performing the manufacturing operations described in the present disclosure.  FIG. 8A  shows system  800  in an open configuration. Fixtures  804  and  806  can position substrate  102  and interconnect component  202  respectively. In addition, fixtures  804  and  806  can be hingedly coupled by rotation servo  808 , allowing fixture  804  and fixture  806  to rotate relative to one another. Positioning features  810  and  812  can move substrate  102  and interconnect component  202  respectively to align the components properly within fixtures  804  and  806 . In some embodiments, sensors  814  can be provided to sense the positions of substrate  102  and interconnect component  202  to aid in the alignment process. Sensors  814  can include mechanical sensors, optical sensors, or any other sensor capable of detecting the position of substrate  102  and interconnect component  202 . In some embodiments, the position of substrate  102  and interconnect component  202  can be adjusted manually in response to inputs from sensors  814 . In other embodiments, controller  802  can automate the process by automatically directing positioning features  810  and  812  to position substrate  102  and interconnect component  202  in response to input signals from sensors  814 . Controller  802  can also direct rotation servo  808  to rotate fixture  806  into a closed position once the alignment process is complete. 
       FIG. 8B  shows system  800  in a closed position. Once fixture  806  is rotated relative to fixture  804 , interconnect component  202  is positioned above substrate  102  with the bonding pads on each component aligned with one another. An opening can be provided in fixture  806  to provide access to nozzle  816 . Nozzle  816  can dispense conductive compound  208  through apertures provided in interconnect component  202  using a variety of methods including printing processes, jetting processes, thermal sintering processes, and any other technically feasible means of precisely applying conductive compound  208  to the assembly. In some embodiments, heating element  818  can be embedded in fixture  804  or fixture  806  to aid in curing conductive compound  208 . If an adhesive layer is included in the assembly, heating element  818  can cure the adhesive layer as well. In other embodiments, the adhesive layer can be cured using other means such as ultraviolet light, time, pressure, or any combination of suitable curing techniques. 
     In some embodiments, controller  802  can automatically control the position of nozzle  816  and amount of conductive compound  208  dispensed by nozzle  816 . In addition, controller  802  can control the temperature of heating element  818 . User inputs can provide operating parameters to controller  802  that can be used to instruct computer code stored within controller  802  on means of implementing the methods described in the present disclosure. In some embodiments, fixtures  804  and  806  can be positioned relative to one another using mechanical arms, a hydraulic press, or any other feasible means of moving one fixture relative to another. 
       FIG. 9  shows a flowchart depicting process  900 , demonstrating a manufacturing process for implementing the various embodiments described in the present disclosure. In step  902 , apertures can be created in an interconnect component. The apertures can extend through both structural elements of the interconnect component and bonding pads intended to interface with a corresponding substrate. The apertures can be formed in a variety of shapes including circles, squares, notches, and any other suitable shape. In some embodiments, the shape of the apertures can vary as a function of depth as well. The apertures can be created using a variety of processes including drilling, laser cutting, etching, or any other technically feasible process for creating apertures. Next, in optional step  904 , an adhesive layer can be applied to either the interconnect component or the substrate. The adhesive layer can provide an additional mechanical connection between the interconnect component and the substrate. The adhesive layer can include an adhesive film, adhesive tape, epoxy resin, or any other suitable adhesive. Furthermore, the adhesive layer can be applied using a laminating process, printing process, manual application, or any other technically feasible means of depositing an adhesive layer. 
     In step  906 , the interconnect component can be aligned to the substrate using a fixture. In one embodiment, a rotating fixture with automatic sensors and alignment features such as system  800  described in  FIG. 8  can be used. In other embodiments, non-rotating fixtures can be used as well. The fixture can align the substrate and interconnect component so that corresponding bonding pads come into contact with one another. Next, in optional step  908 , an adhesive that may have been added in step  904  can be cured. If the adhesive is pressure sensitive, then the fixture can apply the appropriate pressure to form a bond between the substrate and the interconnect component. If the adhesive is heat activated, then the fixture can include a heating feature for curing the adhesives. In other embodiments, the adhesive layer be cured using UV light or a combination of heat and UV light. In some embodiments, the adhesive can be cured at the same time as the conductive compound in step  912 . 
     In step  910 , the conductive compound is deposited along an upper surface of bonding pads included in the interconnect component and injected into the apertures created in step  902 . A variety of different conductive compounds can be used including anisotropic conductive paste (ACP), solder, silver ink, Ag materials, or any other technically feasible compound capable of forming an electrical connection between the bonding pads. In addition, the conductive compound can be applied using a variety of methods including printing processes, jetting processes, thermal sintering processes, and any other technically feasible means of precisely applying the conductive compound. Finally, in step  912 , the conductive compound can be cured. Depending on the compound used, this can involve the application of heat, pressure, time, UV light or any other technically feasible means of curing. In some embodiments, the optional adhesive layer applied in step  904  can be cured at the same time as the conductive compound. 
       FIG. 10  is a block diagram of electronic controller  1000  suitable for controlling some of the processes in the described embodiment. For example, controller  1000  can represent controller  802  in system  800  shown in  FIG. 8 . Controller  1000  illustrates circuitry of a representative computing device. Controller  1000  includes a processor  1002  that pertains to a microprocessor or controller for controlling the overall operation of controller  1000 . Controller  1000  contains instruction data pertaining to manufacturing instructions in a file system  1004  and a cache  1006 . The file system  1004  is, typically, a storage disk or a plurality of disks. The file system  1004  typically provides high capacity storage capability for the controller  1000 . However, since the access time to the file system  1004  is relatively slow, the controller  1000  can also include a cache  1006 . The cache  1006  is, for example, Random-Access Memory (RAM) provided by semiconductor memory. The relative access time to the cache  1006  is substantially shorter than for the file system  1004 . However, the cache  1006  does not have the large storage capacity of the file system  1004 . Further, the file system  1004 , when active, consumes more power than does the cache  1006 . The power consumption is often a concern when the controller  1000  is a portable device that is powered by a battery  1024 . The controller  1000  can also include a RAM  1020  and a Read-Only Memory (ROM)  1022 . The ROM  1022  can store programs, utilities or processes to be executed in a non-volatile manner. The RAM  1020  provides volatile data storage, such as for cache  1006 . 
     The controller  1000  also includes a user input device  1008  that allows a user of the controller  1000  to interact with the controller  1000 . For example, the user input device  1008  can take a variety of forms, such as a button, keypad, dial, touch screen, audio input interface, visual/image capture input interface, input in the form of sensor data, etc. Still further, the controller  1000  includes a display  1010  (screen display) that can be controlled by the processor  1002  to display information to the user. A data bus  1016  can facilitate data transfer between at least the file system  1004 , the cache  1006 , the processor  1002 , and a CODEC  1013 . The CODEC  1013  can be used to decode and play a plurality of media items from file system  1004  that can correspond to certain activities taking place during a particular manufacturing process. The processor  1002 , upon a certain manufacturing event occurring, supplies the media data (e.g., audio file) for the particular media item to a coder/decoder (CODEC)  1013 . The CODEC  1013  then produces analog output signals for a speaker  1014 . The speaker  1014  can be a speaker internal or external to the controller  1000 . For example, headphones or earphones that connect to the controller  1000  would be considered an external speaker. 
     The controller  1000  also includes a network/bus interface  1011  that couples to a data link  1012 . The data link  1012  allows the controller  1000  to couple to a host computer or to accessory devices. The data link  1012  can be provided over a wired connection or a wireless connection. In the case of a wireless connection, the network/bus interface  1011  can include a wireless transceiver. The media items can be any combination of audio, graphical or visual content. Sensor  1026  can take the form of circuitry for detecting any number of stimuli. For example, sensor  1026  can include any number of sensors for monitoring a manufacturing operation such as for example, a mechanical positioning sensor, an optical or laser sensor, a Hall Effect sensor responsive to external magnetic field, an audio sensor, a light sensor such as a photometer, and so on. 
     The various aspects, embodiments, implementations or features of the described embodiments can be used separately or in any combination. Various aspects of the described embodiments can be implemented by software, hardware or a combination of hardware and software. The described embodiments can also be embodied as computer readable code on a computer readable medium for controlling manufacturing operations or as computer readable code on a computer readable medium for controlling a manufacturing line. The computer readable medium is any data storage device that can store data which can thereafter be read by a computer system. Examples of the computer readable medium include read-only memory, random-access memory, CD-ROMs, HDDs, DVDs, magnetic tape, and optical data storage devices. The computer readable medium can also be distributed over network-coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. 
     The foregoing description, for purposes of explanation, used specific nomenclature to provide a thorough understanding of the described embodiments. However, it will be apparent to one skilled in the art that the specific details are not required in order to practice the described embodiments. Thus, the foregoing descriptions of specific embodiments are presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the described embodiments to the precise forms disclosed. It will be apparent to one of ordinary skill in the art that many modifications and variations are possible in view of the above teachings.

Metadata:
Filing Date: 20130424
Publication Date: 20160621
Grant Date: 20160621
Priority Date: 20130424
Inventors: SUNG KUO-HUA
GRESPAN SILVIO
Assignee: APPLE INC
CPC Classifications: [{"code": "H05K3/363", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/09572", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/09854", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/0979", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/118", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K2201/09481", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K3/361", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/0969", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/117", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2203/0126", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R12/62", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R43/0249", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01R12/62", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/09572", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K3/363", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/0969", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/09481", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/118", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K2201/09854", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K3/361", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2203/0126", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01R43/0249", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/0979", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K1/117", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 51789109