PATENT DOCUMENT

Publication Number: US-10424438-B2
Application Number: US-201615275369-A
Country: US
Kind Code: B2

Title: Reduced electrical terminations in surface-mount technology components

Abstract:
Systems and methods described in this disclosure are related to fabrication and utilization of two-terminal electrical components that may have terminations with reduced width. Components, such as the ones described herein may be used to increase the density of components in electrical devices, as they may reduce a separation distance between devices that lead to solder bridging. Methods for fabrication are also described, including the use of ceramic layers that may provide reduction in parasitic capacitance and/or inductances.

Claims:
What is claimed is: 
     
       1. An electrical component comprising:
 a first electrical termination disposed along a bottom of the electrical component, a first terminal edge of the electrical component that abuts a first end of the electrical component and the first end of the electrical component extending to a third terminal edge of the electrical component that abuts a top of the electrical component, wherein a first portion of the first electrical termination disposed in the first end of the electrical component comprises a trapezoidal shape; and 
 a second electrical termination disposed along the bottom of the electrical component and extending to a second terminal edge of the electrical component that abuts a second end of the electrical component opposite to the first end of the electrical component, 
 wherein the first electrical termination is disposed at a first distance from a first and a second corner of the first terminal edge, the first distance corresponding to at least 10% of a total length of the first terminal edge, wherein the first distance is measured along the first terminal edge and the first electrical termination is disposed at a second distance from a third and a fourth end of the third terminal edge, wherein the second distance is smaller than the first distance, and wherein the second distance is measured along the third terminal edge. 
 
     
     
       2. The electrical component of  claim 1 , wherein the trapezoidal shape of the first portion of the first electrical termination is substantially similar to a shape of a second portion of the second electrical termination disposed in the second end of the electrical component. 
     
     
       3. The electrical component of  claim 1 , wherein the first electrical termination extends contiguously along the first end and the top of the electrical component. 
     
     
       4. The electrical component of  claim 1 , wherein the electrical component is configured to be mounted to a printed circuit board (PCB) using a surface-mount technique (SMT). 
     
     
       5. The electrical component of  claim 1 , wherein the electrical component comprises a multilayer ceramic capacitor. 
     
     
       6. The electrical component of  claim 1 , wherein a width of the first electrical termination along the first terminal edge is 50 μm smaller than the total length of the first terminal edge. 
     
     
       7. The electrical component of  claim 1 , wherein the first electrical termination covers the third terminal edge. 
     
     
       8. A multilayer ceramic capacitor comprising:
 a first electrical termination disposed along a bottom and a first end of the multilayer ceramic capacitor, wherein a first region of the first electrical termination disposed in the first end of the multilayer ceramic capacitor comprises a first terminal edge that abuts the bottom of the multilayer ceramic capacitor and a second terminal edge that abuts a top of the multilayer ceramic capacitor, wherein a first width of the first electrical termination along the first terminal edge is smaller than a second width of the first electrical termination along the second terminal edge to form a first trapezoidal shape, wherein the first width is less than 80% of an edge width of the multilayer ceramic capacitor along the first terminal edge, and wherein the first electrical termination is the only termination contacting the first end of the multilayer ceramic capacitor; and 
 a second electrical termination disposed along the bottom and a second end of the multilayer ceramic capacitor, wherein a second region of the second electrical termination disposed in the second end of the multilayer ceramic capacitor comprises a third terminal edge that abuts the bottom of the multilayer ceramic capacitor and a fourth terminal edge that abuts the top of the multilayer ceramic capacitor, and wherein a third width of the second electrical termination along the third terminal edge is smaller than a fourth width of the second electrical termination along the fourth terminal edge to form a second trapezoidal shape; 
 a first layer comprising a first electrode, wherein the first electrode comprises a first lip coupled to the first electrical termination along a first electrode edge of the first layer; and 
 a second layer comprising a second electrode, wherein the second electrode comprises a second lip coupled to the second electrical termination along a second electrode edge of the second layer, 
 wherein a dimension of the first lip measured along the first electrode edge is less than a total length of the first electrode edge and a second dimension of the second lip measured along the second electrode edge is less than a total length of the second electrode edge. 
 
     
     
       9. The multilayer ceramic capacitor of  claim 8 , wherein the first electrode comprises rounded corners. 
     
     
       10. The multilayer ceramic capacitor of  claim 8 , wherein the second electrode comprises a third lip coupled to the second electrical termination along the second electrode edge of the second layer. 
     
     
       11. The multilayer ceramic capacitor of  claim 8 , wherein the first layer is disposed in a plane parallel to the bottom of the multilayer ceramic capacitor. 
     
     
       12. The multilayer ceramic capacitor of  claim 8 , wherein the first layer is disposed in a plane perpendicular to the bottom of the multilayer ceramic capacitor. 
     
     
       13. The multilayer ceramic capacitor of  claim 8 , wherein the first electrical termination comprises a third region along the bottom of the multilayer ceramic capacitor and a fourth region along the top of the multilayer ceramic capacitor, the second electrical termination comprises a fifth region along the bottom of the multilayer ceramic capacitor and a sixth region along the top of the multilayer ceramic capacitor, and the multilayer ceramic capacitor is configured to mount to a printed circuit board through coupling of the third and the fifth region, and the multilayer ceramic capacitor is configured to mount to an electrical component through the fourth region and the sixth region. 
     
     
       14. The multilayer ceramic capacitor of  claim 8 , wherein the second width of the first electrical termination along the second terminal edge is similar to a width of the multilayer ceramic capacitor measured along the second terminal edge. 
     
     
       15. An electrical device, comprising:
 a printed circuit board comprising a first electrical pad and a second electrical pad; and 
 a component comprising: 
 a first electrical termination electrically coupled to the first electrical pad, disposed along a bottom of the component, a first terminal edge of the component that abuts a first end of the component, and the first end of the component extending to a third terminal edge of the component that abuts a top of the component, and wherein a first portion of the first electrical termination disposed in the first end of the component comprises a trapezoidal shape the first electrical termination is disposed at a first distance from a first and a second corner of the first terminal edge measured along the first terminal edge, the first distance corresponds to at least 10% of a total length of the first terminal edge, the first electrical termination is disposed at a second distance from a third and a fourth corner of the third terminal edge measured along the third terminal edge, and the second distance is smaller than the first distance; and 
 a second electrical termination electrically coupled to the second electrical pad, disposed along the bottom of the component, and extending to a second terminal edge of the component that abuts a second end of the component opposite to the first end of the component. 
 
     
     
       16. The electrical device of  claim 15 , wherein a first width of the first electrical pad is substantially similar to a second width of the first electrical termination measured along the first terminal edge. 
     
     
       17. The electrical device of  claim 15 , wherein the component comprises a multilayer ceramic capacitor. 
     
     
       18. The electrical device of  claim 15 , wherein the component is electrically coupled to the printed circuit board using a surface-mount technique (SMT).

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of U. S. Provisional Application No. 62/280,037 entitled “Method and Process for Reducing Solder Bridging between Surface Mount Technology Components” filed on Jan. 18, 2016, which is incorporated by reference herein its entirety for all purposes 
    
    
     BACKGROUND 
     The present disclosure relates generally to packaging of electrical devices and techniques for attachment to a circuit board or integrated circuit. More specifically, techniques for the design and fabrication of electrical terminations and/or connections of that may be used for surface-mount technologies (SMT) and other packaging standards and techniques are described. 
     This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. 
     Proper attachment of an electrical component to a printed circuit board (PCB) may employ an electrical pad on the PCB with a footprint that corresponds to the metallization located in the bottom of the electrical component. The footprint shape may also depend on a mount technique standard and/or the method to mount the electrical component to the PCB. For example, in electrical components that may use a surface-mount technique (SMT) the metallization on the bottom of SMT components usually extend from one end of the device to the other. As a result, the SMT pad on the PCB, as well as the corresponding solder junction between the SMT component and the PCB, may have a large footprint having a large metallization area. 
     During the process of attaching electrical components to the PCB, separation between neighboring electrical pads may be useful to prevent fabrication damages. For example, if two neighboring electrical pads are too close, the soldering process may result in the generation of an unintended short-circuit from residuals of the solder flux (e.g., solder bridging). The potential for solder bridging may increase the minimum distance between two neighboring electrical components, and consequently, limit the component density in the PCB. This may lead to electrical devices with large PCBs. 
     SUMMARY 
     A summary of certain embodiments disclosed herein is set forth below. It should be understood that these aspects are presented merely to provide the reader with a brief summary of these certain embodiments and that these aspects are not intended to limit the scope of this disclosure. Indeed, this disclosure may encompass a variety of aspects that may not be set forth below. 
     In one embodiment, an electrical component is provided. The electrical component may have a first electrical termination disposed along the bottom of the electrical component and extending to a first terminal edge that abuts a first end of the electrical component. The electrical component may also have a second electrical termination disposed along the bottom of the electrical component and extending to a second terminal edge of the electrical component that abuts a second end of the electrical component. The second end of the electrical component may be located opposite to the first end of the electrical component. In this embodiment, the first electrical termination may be located at a distance from both ends of the first terminal edge such that the distance is at least 10% of the total length of the first terminal edge. Note that the distance may be measured along the first terminal edge. 
     In another embodiment, a multilayer ceramic capacitor (MLCC) is provided. The MLCC may have a first layer that includes a first electrode provided with a first lip coupled to a first electrical termination along a first edge of the first layer. The MLCC may also have a second layer that includes a second electrode provided with a second lip and may be coupled to a second electrical termination along a second edge of the second layer. The dimension of the first lip measure along the first edge may be less than the length of the first edge and a second dimension of the second lip measured along the second edge may be less than the length of the second edge. 
     In another embodiment, a method is provided. The method may include steps for mounting a first surface mount device (SMD) to a first electrical pad of a printed circuit board (PCB). The first SMD may have terminations such that the total width of each termination is smaller than the width of the first SMD. The method may also include steps for mounting a second SMD to a second electrical pad of the PCB. The second SMD may also have terminations such that the total width of each termination is smaller than the width of the second SMD. Note that, in this method, the distance between the first electrical pad and the second electrical pad may be smaller than a metal-to-metal distance chosen to prevent formation of a solder bridge between the first and the second electrical pad. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Various aspects of this disclosure may be better understood upon reading the following detailed description and upon reference to the drawings in which: 
         FIG. 1  is a diagram of an electrical device that may benefit from the inclusion of one or more components with reduced terminations, in accordance with an embodiment; 
         FIG. 2  is a perspective view of a notebook computer that may benefit from the inclusion of components with reduced terminations, in accordance with an embodiment; 
         FIG. 3  is a front view of a hand-held device that may benefit from the inclusion of one or more components with reduced terminations, in accordance with an embodiment; 
         FIG. 4  is a front view of portable tablet computer that may benefit from the inclusion of one or more components with reduced terminations, in accordance with an embodiment; 
         FIG. 5  is a diagram of a desktop computer that may benefit from the inclusion of one or more components with reduced terminations, in accordance with an embodiment; 
         FIG. 6  presents a front and a side view of a wearable electrical device that may benefit from the inclusion of one or more components with reduced terminations, in accordance with an embodiment; 
         FIG. 7  presents a perspective view of a two-terminal component having terminations that disposed along 5 sides and may employ reduced-tip electrodes, in accordance with an embodiment; 
         FIG. 8  presents a perspective view of a two-terminal component having terminations disposed along 3 sides and may employ reduced-tip electrodes, in accordance with an embodiment; 
         FIG. 9  presents a perspective view of a two-terminal component having terminations disposed along the bottom of the component and may employ reduced-tip electrodes, in accordance with an embodiment; 
         FIG. 10  presents a perspective view of a two-terminal component having terminations along 2 sides and may employ reduced-tip electrodes, in accordance with an embodiment; 
         FIG. 11  presents a perspective view of a two-terminal component having filleted terminations along three sides, in accordance with an embodiment; 
         FIG. 12  presents a perspective view of a two-terminal component having filleted terminations along two sides, in accordance with an embodiment; 
         FIG. 13  presents a perspective view of a two-terminal component having filleted terminations along the bottom of the component and may employ reduced-tip electrodes, in accordance with an embodiment; 
         FIG. 14  presents a perspective view of a two-terminal component having trapezoidal shaped terminations, in accordance with an embodiment; 
         FIG. 15  presents a perspective view of an alternative layout for a two-terminal component having trapezoidal shaped terminations, in accordance with an embodiment; 
         FIG. 16  presents a perspective view an example of printed circuit board having two mounted two-terminal components such as the one of  FIG. 13 , in accordance with an embodiment; 
         FIG. 17  illustrates a method for mounting two-terminal components having reduced terminations, such as the ones from  FIGS. 11-13 , in accordance with an embodiment; 
         FIG. 18  presents a layout of a reduced tip electrode that may be used with any of the electrical components illustrated in  FIGS. 1-15 , in accordance with an embodiment; 
         FIG. 19  presents another layout for a reduced tip electrode that may be used with any of the electrical components illustrated in  FIGS. 1-15 , in accordance with an embodiment; 
         FIGS. 20A and 20B  present layouts of reduced tip electrodes that may be used to produce a capacitor with termination layouts similar to the ones illustrated in  FIGS. 1-15 , in accordance with an embodiment; 
         FIGS. 21A and 21B  present a second set of layouts of reduced tip electrodes that may be used to produce a capacitor with termination layouts similar to the ones illustrated in  FIGS. 1-15 , in accordance with an embodiment; 
         FIG. 22  presents another layout for reduced tip electrodes that may be used with any of the electrical components illustrated in  FIGS. 1-15 , in accordance with an embodiment; 
         FIG. 23  presents another layout for reduced tip electrodes that may be used with any of the electrical components illustrated in  FIGS. 1-15 , in accordance with an embodiment; and 
         FIG. 24  presents a side view of a two-terminal component with extended terminations along the top for stacking, in accordance with an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     One or more specific embodiments will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. It should be appreciated that in the development of any such actual implementation, as in any engineering or design project, numerous implementation-specific decisions must be made to achieve the developers&#39; specific goals, such as compliance with system-related and business-related constraints, which may vary from one implementation to another. Moreover, it should be appreciated that such a development effort might be complex and time consuming, but would nevertheless be a routine undertaking of design, fabrication, and manufacture for those of ordinary skill having the benefit of this disclosure. 
     When introducing elements of various embodiments of the present disclosure, the articles “a,” “an,” and “the” are intended to mean that there are one or more of the elements. The terms “comprising,” “including,” and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Additionally, it should be understood that references to “one embodiment” or “an embodiment” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. 
     Some of the described examples include devices that may have a right rectangular prism shape, a rectangular prism shape, or a rectangular cuboid. In the descriptions, references to faces and edges may refer to an orientation of the device with respect to its attachment to a printed circuit board. For example, a bottom of a device may refer to a face of the device that is in contact with the printed circuit board and a top of the device may refer to the opposite side. Note that a side of the device refers to a face of the device that is perpendicular to the surface of the printed circuit board. 
     Note further that an edge of the device refers to segment of lines formed between the corners of the device. For example, an edge formed between a side and the bottom of a device refers to the segment of line in the intersection between the bottom face and the side faced referred to. Moreover, when referring to rectangular prism shapes, the end sides refer to the faces that are formed in the short edge of the bottom face rectangle. 
     Many electrical systems may include PCBs that may employ electrical components. These electrical components, which may be integrated circuits or discrete electrical components, may be attached to the PCB by aligning the electrical terminations of the components to exposed conductor (e.g., pads) located in the PCB. Through soldering or some other method for fixation, electrical components may be included in electrical circuitries implemented in the PCB. 
     In some techniques for fixations, such as in surface-mount techniques (SMT), soldering may include addition of solder paste between the PCB and the electrical component followed by some soldering step, such as reflow-solder. In this process, unintended short-circuits between neighboring pads (e.g., solder bridging) may be formed accidentally. Note that this type of defect may be observed with other methods of fixation, such as manual soldering, wire soldering, solder ball techniques, and other similar methods. To reduce the risk of solder bridging the spacing between neighboring pads may be increased. 
     To increase the density of electrical components in a PCB, electrical components may employ electrical terminations such as the ones described herein. These electrical terminations may present dimensions that are reduced in comparison with the dimensions of the electrical component itself. These reduced dimension electrical terminations may allow smaller electrical pads. Since the tolerance distances to prevent solder bridging effects and similar effects is related to the distance between the conductive portions of the electrical components, the distance between the electrical components may be reduced, as detailed below. 
     Furthermore, embodiments described herein may include electrodes that may be used to facilitate the fabrication of components having terminations with reduced-dimensions described herein. Some of the examples provide may enable fabrication of components with reduced electrical terminations without parasite capacitances or other undesired effects that may result from the presence of corners in electrodes, as detailed below. Note that the electrodes presented herein may be used in the manufacture of component having reduced dimensions terminations or terminations that have a length substantially similar to the width of the component. 
     With the preceding in mind, a general description of suitable electronic devices that may include and use electrical components with reduced electrical terminations as described above is provided.  FIG. 1  is a block diagram of an electronic device  10 , in accordance with an embodiment of the present disclosure. The electronic device  10  may include, among other things, one or more processor(s)  12 , memory  14 , storage or nonvolatile memory  16 , a display  18 , input structures  22 , an input/output (I/O) interface  24 , network interface  26 , and a power source  28 . The various functional blocks shown in  FIG. 1  may include hardware elements (including circuitry), software elements (including computer code stored on a computer-readable medium), or a combination of both hardware and software elements. Embodiments of electrical components with layout terminations as the ones described herein may be attached to PCBs in the circuitry of the various functional blocks of  FIG. 1  to improve a performance of software and hardware elements. It should be noted that  FIG. 1  is merely one example of a particular implementation and is intended to illustrate the types of components that may be present in electronic device  10 . 
     By way of example, the electronic device  10  may represent a block diagram of a notebook computer  30 A depicted in  FIG. 2 , handheld devices  30 B,  30 C depicted in  FIG. 3  and  FIG. 4 , a desktop computer  30 D depicted in  FIG. 5 , a wearable electronic device  30 E depicted in  FIG. 6 , or similar devices. It should be noted that the processor(s)  12  and/or other data processing circuitry may be generally referred to herein as “data processing circuitry.” Such data processing circuitry may be embodied wholly or in part as software, firmware, hardware, or any combination thereof. Furthermore, the data processing circuitry may be a single contained processing module or may be incorporated wholly or partially within any of the other elements within the electronic device  10 . 
     In the electronic device  10  of  FIG. 1 , the processor(s)  12  and/or other data processing circuitry may be operably coupled with the memory  14  and the nonvolatile storage  16  to perform various algorithms. Such programs or instructions executed by the processor(s)  12  may be stored in any suitable article of manufacture or computer program product that includes one or more tangible, computer-readable media at least collectively storing the instructions or routines, such as the memory  14  and the nonvolatile storage  16 . The memory  14  and the nonvolatile storage  16  may include any suitable articles of manufacture for storing data and executable instructions, such as random-access memory, read-only memory, rewritable flash memory, hard drives, and optical discs. Moreover, programs (e.g., an operating system) encoded on the memory  14  or the nonvolatile storage  16  may also include instructions that may be executed by the processor(s)  12  to allow the electronic device  10  to provide various functionalities. 
     In certain embodiments, the display  18  may be a liquid crystal display (e.g., LCD), which may allow users to view images generated on the electronic device  10 . In some embodiments, the display  18  may include a touch screen, which may allow users to interact with a user interface of the electronic device  10 . Furthermore, it should be appreciated that, in some embodiments, the display  18  may include one or more light emitting diode (e.g., LED, OLED, AMOLED, etc.) displays, or some combination of LCD panels and LED panels. 
     The input structures  22  of the electronic device  10  may allow a user to interact with the electronic device  10  (e.g., pressing a button to increase or decrease a volume level). The I/O interface  24  may allow electronic device  10  to interface with various other electronic devices. The I/O interface  24  may include various communications interfaces, such as universal serial bus (USB) ports, serial communications ports (e.g., RS232), Apple&#39;s Lightning® connector, or other communications interfaces. The network interface  26  may also allow electronic device  10  to interface with various other electronic devices and may include, for example, interfaces for a personal area network (e.g., PAN), such as a Bluetooth network, for a local area network (e.g., LAN) or wireless local area network (e.g., WLAN), such as an 802.11x Wi-Fi network, and/or for a wide area network (e.g., WAN), such as a 3 rd  generation (e.g., 3G) cellular network, 4 th  generation (e.g., 4G) cellular network, or long term evolution (e.g., LTE) cellular network. The network interface  26  may include an interface for, for example, broadband fixed wireless access networks (e.g., WiMAX), mobile broadband Wireless networks (e.g., mobile WiMAX), asynchronous digital subscriber lines (e.g., ADSL, VDSL), digital video broadcasting-terrestrial (DVB-T) and its extension DVB Handheld (DVB-H), Ultra-Wideband (UWB), alternating current (AC) power lines, and so forth. 
     As further illustrated, the electronic device  10  may include a power source  28 . The power source  28  may include any suitable source of power, such as a rechargeable lithium polymer (e.g., Li-poly) battery and/or an alternating current (e.g., AC) power converter. The power source  28  may be removable, such as replaceable battery cell. 
     In certain embodiments, the electronic device  10  may take the form of a computer, a portable electronic device, a wearable electronic device, or other type of electronic device. Such computers may include computers that are generally portable (e.g., such as laptop, notebook, and tablet computers) as well as computers that are generally used in one place (e.g., such as conventional desktop computers, workstations and/or servers). In certain embodiments, the electronic device  10  in the form of a computer may be a model of a MacBook®, MacBook® Pro, MacBook Air®, iMac®, Mac® mini, or Mac Pro® available from Apple Inc. By way of example, the electronic device  10 , taking the form of the notebook computer  30 A, is illustrated in  FIG. 2  in accordance with an embodiment of the present disclosure. The depicted computer  30 A may include a housing or enclosure  32 , a display  18 , input structures  22 , and ports of the I/O interface  24 . In one embodiment, the input structures  22  (e.g., such as a keyboard and/or touchpad) may be used to interact with the computer  30 A, such as to start, control, or operate a GUI or applications running on computer  30 A. For example, a keyboard and/or touchpad may allow a user to navigate a user interface or application interface displayed on display  18 . 
       FIG. 3  depicts a front view of a handheld device  30 B, which represents an embodiment of the electronic device  10 . The handheld device  30 B may represent, for example, a portable phone, a media player, a personal data organizer, a handheld game platform, or any combination of such devices. By way of example, the handheld device  30 B may be a model of an iPod® or iPhone® available from Apple Inc. of Cupertino, Calif.  FIG. 4  depicts a front view of another handheld device  30 C, which represents another embodiment of the electronic device  10 . The handheld device  30 C may represent, for example, a tablet computer, or one of various portable computing devices. By way of example, the handheld device  30 C may be a tablet-sized embodiment of the electronic device  10 , which may be, for example, a model of an iPad® available from Apple Inc. of Cupertino, Calif. 
     The handheld devices  30 B and  30 C may each include similar components. For example, an enclosure  36  may protect interior components from physical damage. Enclosure  36  may also shield the handheld devices  30 B and  30 C from electromagnetic interference. The enclosure  36  may surround the display  18 , which may display indicator icons  39 . The indicator icons  39  may indicate, among other things, a cellular signal strength, Bluetooth connection, and/or battery life. The I/O interfaces  24  may open through the enclosure  36  and may include, for example, an I/O port for a hard wired connection for charging and/or content manipulation using a connector and protocol, such as the Lightning connector provided by Apple Inc., a universal service bus (e.g., USB), one or more conducted radio frequency connectors, or other connectors and protocols. 
     User input structures  22 ,  40 , in combination with the display  18 , may allow a user to control the handheld devices  30 B or  30 C. For example, the input structure  40  may activate or deactivate the handheld device  30 B or  30 C, one of the input structures  22  may navigate a user interface of the handheld device  30 B or  30 C to a home screen, a user-configurable application screen, and/or activate a voice-recognition feature of the handheld device  30 B or  30 C, while other of the input structures  22  may provide volume control, or may toggle between vibrate and ring modes. In the case of the handheld device  30 B, additional input structures  22  may also include a microphone may obtain a user&#39;s voice for various voice-related features, and a speaker to allow for audio playback and/or certain phone capabilities. 
     Turning to  FIG. 5 , a computer  30 D may represent another embodiment of the electronic device  10  of  FIG. 1 . The computer  30 D may take any suitable form of computer, such as a desktop computer, a server, or a notebook computer, but may also be a standalone media player or video gaming machine. By way of example, the computer  30 D may be an iMac®, a MacBook®, or other similar device by Apple Inc. It should be noted that the computer  30 D may also represent a personal computer (e.g., PC) by another manufacturer. A similar enclosure  36  may be provided to protect and enclose internal components of the computer  30 D such as a dual-layer display. In certain embodiments, a user of the computer  30 D may interact with the computer  30 D using various peripheral input devices, such as input structures  22  (e.g., the keyboard or mouse  38 ), which may connect to the computer  30 D via a wired I/O interface  24  and/or wireless I/O interface. 
     Similarly,  FIG. 6  depicts a wearable electronic device  30 E representing another embodiment of the electronic device  10  of  FIG. 1  that may be configured to operate using the techniques described herein. By way of example, the wearable electronic device  30 E, which may include a wristband  44 , may be an Apple Watch® by Apple, Inc. However, in other embodiments, the wearable electronic device  30 E may include any wearable electronic device such as, for example, a wearable exercise monitoring device (e.g., pedometer, accelerometer, heart rate monitor), or other device by another manufacturer. The display  18  of the wearable electronic device  30 E may include a touch screen (e.g., LCD, OLED display, active-matrix organic light emitting diode (e.g., AMOLED) display, and so forth), which may allow users to interact with a user interface of the wearable electronic device  30 E. 
     With the preceding in mind,  FIG. 7  illustrates a perspective view of a two-terminal component  102  that may employ some of the electrode layouts detailed below. The two-terminal component  102  may have two electrical terminations  104 A and  104 B. Each of the terminations  104 A and  104 B is formed along 5 faces of the device. For example, termination  104 A may be formed along a top  106 A, sides  106 B and  106 F, a bottom  106 C, and an end  106 D. Termination  104 B may be formed along the opposite end  106 E and along top  106 A, sides  106 B and  106 F, and bottom  106 C. 
     Two-terminal component  102  may be any type of component such as a resistor, a capacitor, an inductor, a diode, a memristor or any other type of two-terminal component. Two-terminal component  102  may be soldered to a printed circuit board using a surface-mount technology, welding. In some implementations, terminations  104 A and  104 B may be provided with a solder ball or a solder paste, for ease of placement and assembly to a printed circuit board. 
     Another example of a termination layout that may be used with electrodes detailed below includes two-terminal component  112  of  FIG. 8 . Two-terminal component  112  may have terminations  114 A and  114 B that are formed along 3 faces of the device. For example, termination  114 A may be formed along top  116 A, bottom  116 C and end  116 D and termination  114 B may be formed along top  116 A, bottom  116 C, and end  116 F. Note that the sides  116 B and  116 F are not covered with any metallization in this example. This may prevent a build-up of residual soldering materials along sides  116 B and  116 F of the two-terminal component  112  and reduce the chance of solder bridging. 
     The two-terminal component  122  illustrated in  FIG. 9  is another example of a component that may be mounted to a printed circuit board. In this example, two-terminal component  122  may include terminations  124 A and  124 B that may be formed along the bottom  126 C of the two-terminal component  122 . Note that the termination  124 A is formed along the terminal edge  128 A that is formed between bottom  126 C and end  126 D. Similarly, termination  124 B may extend along the terminal edge  128 B, is formed between bottom  126 C and end  126 E. As a result, top  126 A, sides  126 B and  126 F, and ends  126 D and  126 E are not covered with any metallization in this example. As mentioned above, this feature may prevent a build-up of residual soldering materials along sides  126 B and  126 F, and ends  126 D and  126 E of the two-terminal component  122  and reduce the chance of solder bridging. 
     Another example of a termination layout that extends through an entire width of a two-terminal component  132  is illustrated in  FIG. 10 . The terminations  134 A and  134 B of the two-terminal component  132  may be formed along the bottom  136 C. Moreover, termination  134 A is formed along end  136 D and termination  134 B is formed along end  136 E. Top  136 A and sides  136 B and  136 F are not covered with any metallization in this example, which may prevent undesired build-up of residual materials during the attachment process as discussed above. While some of the above examples may be benefitted by the utilization of the electrodes as detailed below and may reduce some solder bridging, the solder bridging may be further reduce through a reduction of a width of the termination, as detailed below. 
     For example, two-terminal component  142  illustrated in  FIG. 11  illustrates an example of an electrical component having reduced termination dimensions. Two-terminal component  142  may have a termination  144 A that is formed along a top  146 A, a bottom  146 C, and an end  146 D, and a second termination  144 B that is formed along top  146 A, a bottom  146 C, and an end  146 E. Sides  146 B and  146 F are not covered with any metallization, which, as discussed above, may prevent undesired build-up of residues in along the sides  146 B, and  146 F of the two-terminal component  142 . 
     Note, moreover, that a width of termination  144 A is smaller than the length of the edge  149 A formed between bottom  146 C and end  146 D. Note that the width is measured along edge  149 A. For example, the length of termination  144 A may be 10%, 25%, 50%, or 75% of edge  149 A. Note that the distance  148  resulting from the differences between the width of termination  144 A and the length of edge  149 A lead to at least one region along the bottom  146 C and end  146 D that is not covered by any metallization. The dimensions of termination  144 A may also be observed in termination  144 B. As a result of these filleted terminations (e.g., reduced-dimension termination, thinner terminations), the pad on a PCB to which the two-terminal component  142  is to be attached to can be smaller, which may allow an increase in the component density of the PCB, as detailed below. 
     Another two-terminal component  152  with filleted terminations is illustrated in  FIG. 12 . Filleted terminations  154 A and  154 B may be formed along bottom  156 B. Filleted termination  154 A is also formed along an end  156 D and filleted termination  154 B is also formed along end  156 E. Top  156 A and sides  156 B and  156 F are not covered with any metallization in this example, which may prevent undesired build-up of residual materials during the attachment process as discussed above. As with two-terminal component  142 , the pad to which two-terminal component  152  may employ a pad on a PCB with reduced dimensions, which may allow increase in the component density of the PCB. 
     Finally, two-terminal component  162  in  FIG. 13  illustrates a layout for a component having filleted terminations  164 A and  164 B that are formed only along bottom  166 B. In this example, top  166 A, sides  166 C and  166 F, and ends  166 D and  166 E are not covered with any metallization from the termination to prevent build-up that may lead to solder bridging. Moreover, the filleted termination  164 A and  164 B may present a distance  148  from the corner, which may lead to an increase in the density of components in a printed circuit board, as discussed below. 
     Two-terminal component  172  of  FIG. 14  illustrates a component having a trapezoidal arrangement for terminations  174 A and  174 B. The portion of termination  174 A along top  176 A may be rectangular portion. Similarly, the portion of termination  174 A along bottom  176 C may also be a rectangular portion. The portion of termination  174 A along end  176 D may be a trapezoidal shape. As a result the distance between the width of termination  174 A and the width of the two-terminal component  172  may lead to a separation  178 A along edge  179 A that may be smaller than separation  178 B along edge  179 B. This tapering of a dimension of termination  174 A may provide further control of the build-up of residues during the soldering process, and may lead to improved electrical performance in circumstances where another component may be stacked above two-terminal component  172 . 
     Two-terminal component  182  of  FIG. 15  illustrates another design for a component having a trapezoidal arrangement for termination  184 A and  184 B. As illustrated, the termination  184 A may have a width that is flush with edge  189 A. Note however, that the difference between the width of termination  184 A and the length of edge  189 B leads to a distance  188 . As discussed above, the tapering of a dimension of termination  184 A may provide control over the residues from attachment processes, and may lead to more flexible assembly methods, such as stacking of components. Note that the tapering in the examples  172  and  182  may be inverted (e.g., termination thinner at the bottom than at the top), to allow for a reduced electrical pad in a PCB and a wider region on the top for stacking or other type of assembly electrical coupling. 
     The arrangement  200  of  FIG. 16  illustrates two electrical components  202  and  204  attached to a PCB  206 . Electrical component  202  presents filleted terminations  210  and electrical component  204  presents filleted terminations  212 . As discussed above, filleted terminations  210  and  212  provide a distance  214  between the end of a terminations  210  and  212 , and the corner of the corresponding electrical components  202  and  204 . This distance  214  may allow increased density of components through reduction of separation  216  between the components, as detailed below. 
     A tolerance margin  218  based on a minimal metal-to-metal distance between adjacent components may be established in the design process to prevents solder bridging from occurring. The narrower dimensions of the filleted termination  212  compared to a width of electrical components  202  and  204  provides a distance  214  between the corner of the component and the exposed metal relevant to the tolerance margin. As a result, the separation  216  between the electrical components  202  and  204  may be smaller than the tolerance margin  218 , while still maintaining the minimal metal-to-metal distance between filleted termination  210  and filleted termination  212 . For example, if distance  214  in components  202  and  204  is 25 μm and the tolerance margin  218  is 75 μm the separation  216  may be 25 μm, which is 50 μm smaller than the tolerance margin  218 . 
     As a further example of potential space-saving characteristic, consider a system having N electrical components devices similar to components  210  and  212 . Consider further that each of the components have a length  220  equal to L. Assuming that the separation  216  is represented by T, and the tolerance margin  218  is represented by D, the use of components  210  and  212  having a distance  214  between the end of the termination and a corner, the area saved by using filleted terminations  210  may be equal to A=((D−T)*L)*(N−1). 
     With the preceding in mind,  FIG. 17  illustrates a method  350  to assemble circuitries using surface mount two-terminal components with filleted terminations as the ones described in  FIGS. 11-15 . In a process inclusive of the method  350 , a PCB may be designed to include electrical pads disposed to take into account the reduced spacing requirements discussed above (step  352 ). The dimensions of the electric pads may also be adjusted based on the dimensions of the filleted terminations. 
     A solder paste may be applied to the electrical pads in another process (step  354 ). This process may be adjusted based on alternative methods for soldering. For example, components may be provided with solder balls. Components may be then positioned above the designated positions such that the terminations align with the electrical pads (step  356 ). As noted above, the distance between neighboring components may be reduced compared to the distance for components that do not include filleted terminations. The printed circuit board with the components may then undergo a reflow-solder process to attach the components to the PCB (step  358 ). It should be understood that the above-described method  350  may be used to produce circuitries having reduced spacing between components provided with filleted terminations. 
     The two-terminal electrical components described in  FIGS. 7-15  may be constructed using methods such as multilayer ceramic techniques. In these methods, sheets of ceramic may be stenciled in certain portions with a conductive material to form electrodes. Based on the desired role of the component (e.g, resistor, capacitor, inductor), ceramic sheets stenciled with the appropriate electrodes may be produced and stacked to form an electrical component. In order to provide a termination, electrodes may be stenciled such that an electrode may reach a boundary of the ceramic layer and provide a contact region. Electrical components having filleted terminations, such as the ones discussed above, may benefit from a narrow contact region to reduce fabrication defects, and unintended short circuits. 
     The layout  400  in  FIG. 18  illustrates a ceramic layer  402  having a stenciled electrode  404 . Electrode  404  may have a lip  406  at an end of the ceramic layer to provide a contact region. Note that the width of the lip  406  is significantly smaller than the width of the ceramic layer  402 . The lip  406  may, alternatively, be as large as the entire width of the ceramic layer  402 , based on the width of the metallic termination to be provided. Note that electrode  404  include sharp corners  408  and  410 . This layout  400  may be used to produce a two-terminal capacitor by using multiple stenciled sheets interleaved with dielectric sheets. This layout  400  may also be used to produce inductors and resistors, by a stack of sheets in which the electrodes are connected to obtain the desired electrical behavior (i.e., inductance and/or resistance). 
     The presence of sharp corners  404  and  408  may lead to an increased in parasitic inductances, capacitances or resistances, as it may interfere with the flux of electrons during operation of the component. Layout  420  in  FIG. 19  illustrates a ceramic layer  422  with an electrode  424  having a lip  426 . The width of lip  426  may be substantially similar to that of lip  406 . Note further that that the electrode  424  include curved corners  428  and  430 , which may reduce parasitic effects, as discussed above. 
     Layouts  450  of  FIG. 20A and 470  of  FIG. 20B  provide additional examples of ceramic layers  452  and  472 , respectively, that may be used to form a capacitor. Ceramic layer  452  may have an electrode  454  that has a lip  456  to produce a termination. Ceramic layer  472  may include an electrode  474  having lips  476  that may be used to produce other terminations. By interleaving ceramic layers  452  and  472  with dielectric layers, it is possible to forma a multilayer ceramic capacitor (MLCC) with filleted terminations. Note that based on the arrangement of the electrodes, this capacitor may have a central termination (location of lip  456 ) connected to electrodes  454 , and corner terminations (location of lips  476 ). All locations may be extended along the bottom of the formed capacitor. 
     Electrodes  454  and  474  may have sharp corners  458  and  478 . As discussed above, sharp corners may lead to undesired behavior. Layouts  500  of  FIG. 21A and 520  of  FIG. 20B  provide an alternative design for electrodes  504  and  524  located in ceramic layers  502  and  522  that employ rounded corners  508  and  528 . Note that electrodes  504  and  524  have lips  506  and  526 , respectively, which are located in regions similar to lips  456  and  476  of layouts  450  and  470 , respectively. 
     An additional layout  550  for a two-terminal multilayer ceramic component is illustrated in  FIG. 22 . The ceramic layer  552  may have an electrode  554  with lip  556 . As noted above, lip  556  is reduced in width with respect to a width of the ceramic layer  556 . In this layout  550 , the shape of the ceramic layer  552  is square. This square ceramic layer  552  allows for a rounded electrode  554  with no straight edges, which may reduce undesired effects such as parasitic capacitances and/or inductances. 
     Layout  570  in  FIG. 23  may to produce a multi-terminal component having filleted terminations. Ceramic layer  572  may be stenciled with an electrode  574 , which may have rounded corners  576 . Moreover, ceramic layer  572  presents lips  578 A-D that may be used to form filleted terminations. 
     As described above, in some implementations, electrical components may be stacked above the two-terminal components described herein. Two-terminal component  602  illustrated in  FIG. 24  illustrates a layout for terminations  604 A and  604 B that may facilitate stacking. Specifically, top portion  606  of termination  604 A and top portion  608  of termination  604 B may be longer than the bottom portion  610  of termination  604 A and bottom portion  612  of termination  604 B. Note that these terminations may have the filleted profile (e.g., a narrow termination), as discussed above. This design may allow for a more solid support for a component soldered to the top portions  606  and  608  of two-terminal component  602  and increased density by having smaller bottom portions  610  and  612 . 
     The systems and methods described in this disclosure may improve the density of components in a printed circuit board, which may ultimately lead to a reduction in size of electrical devices employing this system. Moreover, performance of the electrical device may improve due to reduction in parasitic effects due to the characteristics of the devices described herein. 
     The specific embodiments described above have been shown by way of example, and it should be understood that these embodiments may be susceptible to various modifications and alternative forms. It should be further understood that the claims are not intended to be limited to the particular forms disclosed, but rather to cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure. 
     The techniques presented and claimed herein are referenced and applied to material objects and concrete examples of a practical nature that demonstrably improve the present technical field and, as such, are not abstract, intangible or purely theoretical. Further, if any claims appended to the end of this specification contain one or more elements designated as “means for [perform]ing [a function] . . . ” or “step for [perform]ing [a function] . . . ”, it is intended that such elements are to be interpreted under 35 U.S.C. 112(f). However, for any claims containing elements designated in any other manner, it is intended that such elements are not to be interpreted under 35 U.S.C. 112(f).

Metadata:
Filing Date: 20160924
Publication Date: 20190924
Grant Date: 20190924
Priority Date: 20160118
Inventors: MARTINEZ, PAUL A.
MEAD, CURTIS C.
MORRISON, SCOTT D.
DE LA CRUZ, GIANCARLO F.
CHEN, LIN
WANG, ALBERT
SIMERAL, BRAD W
VO, VU
CHEN, WYEMAN
Assignee: APPLE INC
CPC Classifications: [{"code": "H05K2201/10636", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K3/3442", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01G4/012", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01G4/232", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K2201/10015", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01G4/012", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01G4/232", "inventive": true, "first": true, "tree": "[]"}, {"code": "H01G2/065", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K2201/10636", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/10015", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01G4/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01G2/065", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01G4/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K3/3442", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01G2/065", "inventive": true, "first": false, "tree": "[]"}, {"code": "H05K3/3442", "inventive": false, "first": false, "tree": "[]"}, {"code": "H01G4/012", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01G4/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "H01G4/232", "inventive": true, "first": true, "tree": "[]"}, {"code": "H05K2201/10015", "inventive": false, "first": false, "tree": "[]"}, {"code": "H05K2201/10636", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y02P70/50", "inventive": false, "first": false, "tree": "[]"}, {"code": "Y02P70/50", "inventive": false, "first": false, "tree": "[]"}]
Family ID: 59315257