Patent Publication Number: US-2011062482-A1

Title: Apparatus And Method For Enhancing Connectability In LED Array Using Metal Traces

Description:
FIELD 
     The exemplary aspect(s) of the present invention relates to lighting devices. More specifically, the aspect(s) of the present invention relates to light-emitting semiconductor fabrication with flexible LED connections capable of reconfiguring electrical connections of light emitting diodes (“LED”) dice. 
     BACKGROUND 
     Solid-state light-emitting devices such as LEDs are attractive candidates for replacing conventional light sources such as incandescent and fluorescent lamps. LEDs typically have higher light conversion efficiencies than incandescent lamps, and have longer lifetime than conventional light sources. Certain types of LEDs, for instance, have higher light conversion efficiencies than fluorescent light sources and even higher conversion efficiencies have been demonstrated in the laboratory. For LEDs to be accepted in various lighting applications, it is important to optimize every step of the processing and achieve the highest efficiencies possible. 
     A physical characteristic associated with a conventional LED lighting system having multiple LED dice is performance variation in connection to the source of power supply. For example, LED dice connected in series tend to produce more flux for a fixed amount of current than the LED dice connected in parallel. As such, LED dice connected in series performs well for a fixed amount of current source with high voltage. Conversely, LED dice connected in parallel configuration tend to provide more flux with a power source that provides high current and low voltage than a power source with low current and high voltage. Accordingly, the performance of an LED lighting system can vary depending on the availability of the power source. 
     A problem associated with manufacturing a conventional LED light system is the lack of flexibility in LED connections after substrates are fabricated. In other words, changing the LED dice electrical connection after the substrates are fabricated is typically difficult. Due to the tight layout of a conventional LED light system, the flexibility of connecting LED dice in series and/or parallel is limited after the components are formed. 
     SUMMARY 
     A light-emitting device having multiple LED dice organized in an array capable of flexibly configuring LED dice in series, parallel, and/or a combination of series and parallel via metal traces is disclosed. In one aspect, the light-emitting device includes a substrate, a dielectric layer, an LED array, and a set of metal traces. The dielectric layer, which is disposed over the substrate, provides electric insulation. The LED array capable of generating light is able to enhance flexibility of LED connections using one or more metal traces. The metal trace has a predefined shape configured to travel through the LED array for facilitating electric connections in multiple electrical configurations. 
     It is understood that other aspects of the present invention will become readily apparent to those skilled in the art from the following detailed description, wherein it is shown and described only exemplary configurations of an LED by way of illustration. As will be realized, the present invention includes other and different aspects and its several details are able to be modified in various other respects, all without departing from the spirit and scope of the present invention. Accordingly, the drawings and the detailed description are to be regarded as illustrative in nature and not as restrictive. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The exemplary aspect(s) of the present invention will be understood more fully from the detailed description given below and from the accompanying drawings of various aspects of the invention, which, however, should not be taken to limit the invention to the specific aspects, but are for explanation and understanding only. 
         FIG. 1  is a diagram illustrating a lighting system having multiple LED dice with reconfigurable connections in accordance with an aspect of the present invention; 
         FIG. 2  is a diagram illustrating a lighting system having three LED dice capable of providing reconfigurable connections in accordance with an aspect of the present invention; 
         FIG. 3  is a diagram illustrating a lighting system having three LED dice connected in series via a metal trace in accordance with an aspect of the present invention; 
         FIG. 4  is a diagram illustrating a lighting system having four LED dice connected in series via a Z-shaped metal trace in accordance with an aspect of the present invention; 
         FIG. 5  is a diagram illustrating a lighting system having multiple LED dice connected in series using a straight metal trace in accordance with an aspect of the present invention; 
         FIGS. 6A-B  are diagrams showing alternative metal trace shapes used in LED array in accordance with an aspect of the present invention; 
         FIGS. 7A-C  illustrate images showing LED lighting devices capable of reconfiguring LED connections using metal traces in accordance with an aspect of the present invention; 
         FIG. 8A  illustrates an exploded view of a lighting system having an LED array using metal trace for flexible LED connections in accordance with an aspect of the present invention; 
         FIG. 8B  illustrates images of a lighting system having an LED array using metal trace for facilitating flexible LED connections in accordance with an aspect of the present invention; 
         FIG. 9  is a flowchart illustrating a process of fabricating a lighting device having multiple LED dice and a metal trace for reconfigurable connections in accordance with an aspect of the present invention; 
         FIG. 10  is a conceptual cross-sectional view illustrating an exemplary fabrication process of an LED or LED devices; 
         FIG. 11  is a conceptual cross-sectional view illustrating an example of an LED with a phosphor layer; 
         FIG. 12A  is a conceptual top view illustrating an example of an LED array that can be used with flexible LED connections in accordance with an aspect of the present invention; 
         FIG. 12B  is a conceptual cross-sectional view of the LED array of  FIG. 12A ; 
         FIG. 13A  is a conceptual top view illustrating an example of an alternative configuration of an LED array that can be used with flexible LED connections in accordance with an aspect of the present invention; 
         FIG. 13B  is a conceptual cross-sectional view of the LED array of  FIG. 13A ; and 
         FIG. 14  shows exemplary lighting devices including LED devices using flexible LED connections in accordance with an aspect of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Aspects of the present invention is described herein in the context of a method, device, and apparatus of reconfiguring connections of light emitting diode (“LED”) dice organized in an array using one or more metal traces. 
     The present invention is described more fully hereinafter with reference to the accompanying drawings, in which various aspects of the present invention are shown. This invention, however, may be embodied in many different forms and should not be construed as limited to the various aspects of the present invention presented throughout this disclosure. Rather, these aspects are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present invention to those skilled in the art. The various aspects of the present invention illustrated in the drawings may not be drawn to scale. Rather, the dimensions of the various features may be expanded or reduced for clarity. In addition, some of the drawings may be simplified for clarity. Thus, the drawings may not depict all of the components of a given apparatus (e.g., device) or method. 
     Various aspects of the present invention will be described herein with reference to drawings that are schematic illustrations of idealized configurations of the present invention. As such, variations from the shapes of the illustrations as a result, for example, manufacturing techniques and/or tolerances, are to be expected. Thus, the various aspects of the present invention presented throughout this disclosure should not be construed as limited to the particular shapes of elements (e.g., regions, layers, sections, substrates, etc.) illustrated and described herein but are to include deviations in shapes that result, for example, from manufacturing. By way of example, an element illustrated or described as a rectangle may have rounded or curved features and/or a gradient concentration at its edges rather than a discrete change from one element to another. Thus, the elements illustrated in the drawings are schematic in nature and their shapes are not intended to illustrate the precise shape of an element and are not intended to limit the scope of the present invention. 
     It will be understood that when an element such as a region, layer, section, substrate, or the like, is referred to as being “on” another element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another element, there are no intervening elements present. It will be further understood that when an element is referred to as being “formed” on another element, it can be grown, deposited, etched, attached, connected, coupled, or otherwise prepared or fabricated on the other element or an intervening element. 
     Furthermore, relative terms, such as “lower” or “bottom” and “upper” or “top,” may be used herein to describe one element&#39;s relationship to another element as illustrated in the drawings. It will be understood that relative terms are intended to encompass different orientations of an apparatus in addition to the orientation depicted in the drawings. By way of example, if an apparatus in the drawings is turned over, elements described as being on the “lower” side of other elements would then be oriented on the “upper” side of the other elements. The term “lower”, can therefore, encompass both an orientation of “lower” and “upper,” depending of the particular orientation of the apparatus. Similarly, if an apparatus in the drawing is turned over, elements described as “below” or “beneath” other elements would then be oriented “above” the other elements. The terms “below” or “beneath” can, therefore, encompass both an orientation of above and below. 
     Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and this disclosure. 
     As used herein, the singular forms “a”, “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. The term “and/or” includes any and all combinations of one or more of the associated listed items 
     Various aspects of an LED luminaire will be presented. However, as those skilled in the art will readily appreciate, these aspects may be extended to aspects of LED luminaries without departing from the invention. The LED luminaire may be configured as a direct replacement for conventional luminaries, including, by way of example, recessed lights, surface-mounted lights, pendant lights, sconces, cove lights, track lighting, under-cabinet lights, landscape or outdoor lights, flood lights, search lights, street lights, strobe lights, bay lights, strip lights, industrial lights, emergency lights, balanced arm lamps, accent lights, background lights, and other light fixtures. 
     As used herein, the term “light fixture” shall mean the outer shell or housing of a luminaire. The term “luminaire” shall mean a light fixture complete with a light source and other components (e.g., a fan for cooling the light source, a reflector for directing the light, etc.), if required. The term “LED luminaire” shall mean a luminaire with a light source comprising one or more LEDs. LEDs are well known in the art, and therefore, will only briefly be discussed to provide a complete description of the invention. 
     It is further understood that the aspect of the present invention may contain integrated circuits that are readily manufacturable using conventional semiconductor technologies, such as CMOS (“complementary metal-oxide semiconductor”) technology, or other semiconductor manufacturing processes. In addition, the aspect of the present invention may be implemented with other manufacturing processes for making optical as well as electrical devices. Reference will now be made in detail to implementations of the exemplary aspect(s) as illustrated in the accompanying drawings. The same reference indicators will be used throughout the drawings and the following detailed description to refer to the same or like parts. 
     An LED lamp includes multiple LED dice organized in an array which is capable of configuring LED dice in series, parallel, and/or a combination of series and parallel via one or more metal traces. In one aspect, the LED lamp includes a substrate, a dielectric layer, an LED array, and a metal trace. The dielectric layer, which is disposed over at least a portion of the substrate, provides electric insulation. The LED array capable of generating light is able to enhance flexibility of LED connections using one or more metal traces. The metal trace has a predefined shape configured to travel through the LED array to facilitate electric connections. 
       FIG. 1  is a diagram  100  illustrating a lighting system having multiple LED dice with reconfigurable connections in accordance with an aspect of the present invention. Diagram  100  includes an LED array, a substrate  108 , a patterned dielectric layer  106 , and a metal trace  118 , wherein the LED array includes LED dice  110 - 116 . LED dice  110 - 116  are coupled to terminals or pads  102 - 104  using bond wires  120 - 130 . It should be noted that the underlying concept of the exemplary aspect(s) of the present invention would not change if one or more elements (or devices) were added to or removed from diagram  100 . 
     The LED array, in one aspect, includes four (4) LED dice  110 - 116 , wherein each LED die is a semiconductor diode capable of converting electrical energy to optical light. Note that the conversion of electrical energy to optical energy is also known as electroluminescence. The color of the light is generally based on the energy gap of the semiconductor used. The LED array is able to configure layout of LED dice  110 - 116  such as parallel or serial connections after the components are fabricated. Each LED die includes a first electrical contact and a second electrical contact capable of electrically coupling to conductive traces and/or pads. LED dice  110 - 116  are disposed or fastened over substrate  108 . 
     Substrate  108  can be a metal substrate or dielectric substrate. The metal substrate, which is a conductive substrate, can be made of aluminum, nickel, copper, metal alloy, and/or a combination of electrical conductive materials. Alternatively, a dielectric substrate, which is a non-conductive substrate, can be made of non-conductive materials, such as ceramic, plastic, glass, and/or materials for making printed circuit board (“PCB”). As such, depending on applications, substrate  108  can be either made of conductive, non-conductive, or a combination of metal and dielectric materials. 
     Substrate  108 , also known as reconfigurable LED array substrate, is formed with trenches that separate and define sections which house one or more electronic components such as LED dice  110 - 116 . Trenches or traces provide wiring mechanism to facilitate electrical interconnections between individual components. In one example, substrate  108  further includes an integral reflector(s) shaped in a form of cavity (or cavities) to house LED die(s). Reflector cavity walls, for instance, can be optionally plated with reflective materials and/or filled with molding materials used for lens and/or encapsulant. In one aspect, substrate  108  is made of aluminum-aluminum oxide through applicable semiconductor manufacturing technologies such as Aluminum Oxide (“ALOX”) process. Depending on processing technologies, a metal substrate can satisfy manufacturing requirements as well as electrical interconnections, thermal limitations, and desirable mechanical properties. Dielectric layer  106 , in one aspect, is disposed over metal substrate  108  to provide electric insulation. Multiple electrically conductive traces such as metal trace  118  can be subsequently disposed over dielectric layer  106 . In one instance, dielectric layer  106  includes ALOX. 
     Metal trace  118 , in one aspect, is made of electrically conductive materials, such as aluminum, copper, nickel, gold, or a combination of aluminum, copper, nickel, and gold, to facilitate movement of electrical current. Metal trace  118  is an S-shaped metal strip configured to travel through the LED array to enhance electric connectivity. For example, metal trace  118  passes through LED dice  110 - 116  in an LED array, as illustrated in  FIG. 1 , to enhance flexibility of electric connectivity. A function of metal trace  118  is to provide additional wire bond connection(s) thereby LED dice  110 - 116  can be flexibly reconfigured in a parallel connection, series connection, or a combination of series and parallel connections after the components are fabricated. 
     Referring back to  FIG. 1 , a first terminal of LED die  110  is connected to a first terminal of power source  102  via bond wire  124  and a second terminal of LED die  110  is connected to a first terminal of LED die  112  via bond wire  122 . A second terminal of LED die  112  is connected to a second terminal of power source  104 . While a second terminal of LED die  114  is connected to second terminal  104  via bond wire  126 , a first terminal of LED die  114  is connected to a second terminal of LED die  116  via bond wire  128 . A first terminal of LED die  116  is connected to the first terminal of power source  102  via bond wire  130 . Note that the first terminal of power source  102  can be positive potential of a power supply and the second terminal of power source  104  can be negative potential of a power supply. The LED array has two (2) serial strings of LED dice wherein each string includes two LED dice. For example, LED dice  110 - 112  form the first series of LED dice while LED dice  114 - 116  form the second series connection of LED dice. The first series of LED dice  110 - 112  is in parallel with the second series of LED dice  114 - 116 . 
     An advantage of having a metal trace(s) such as metal trace  118  is to provide different number of LED dice to generate a different combination of series and/or parallel connections depending on the specific customer&#39;s requirements. Note that the S-shaped metal trace  118  is for illustrated purposes, the underlying concept of the exemplary aspect(s) of the present invention would not change if metal trace  118  is in an H-shape, Z-shape, I-shape, and/or any other shapes or formations. 
     It should be noted that a metal trace disposed over a substrate can provide different LED interconnection patterns or layout. In addition, it is also advantageous to have a substrate having direct metal connection with low thermal resistance path between a die and a bottom surface of the substrate. 
       FIG. 2  is a diagram  200  illustrating a lighting system having three LED dice capable of providing reconfigurable connections in accordance with an aspect of the present invention. Diagram  200  includes an LED array, a substrate  108 , a dielectric layer  106 , and a metal trace  118 . LED dice  110 - 114  are coupled to terminals or pads  102 - 104  using bond wires  220 - 230 . It should be noted that the underlying concept of the exemplary aspect(s) of the present invention would not change if one or more elements (or devices) were added to or removed from system  200 . 
     The LED array includes three (3) LED dice  110 - 114 , wherein LED dice  110 - 114  are connected in three-way parallel connections using metal trace  118 . Referring back to  FIG. 2 , a first terminal of LED die  110  is connected to a first terminal of power source  102  via bond wire  230  and a second terminal of LED die  110  is connected to metal trace  118  via bond wire  222 . A first terminal of LED die  112  is connected to the first terminal of power source  102  via bond wire  224  and a second terminal of LED die  112  is connected to a second terminal of power source  104  via bond wire  220 . While a second terminal of LED die  114  is connected to metal trace  118  via bond wire  226 , a first terminal of LED die  114  is connected to the first terminal of power source  102  via bond wire  228 . Metal trace  118  is coupled with the second terminal of power source  104  via bond wire  232 . Note that the first terminal of power source  102  can be the positive potential of a power supply and the second terminal of power source  104  can be negative potential of a power supply. Diagram  200  illustrates LED dice in the LED array is configured in three (3) strings in parallel wherein each string contains one LED die. 
     An advantage of using a metal trace is to permit reconfiguration of connectivity of LED dice in accordance with the customer&#39;s specifications while the components such as substrates and metal trace(s) are pre-fabricated. 
       FIG. 3  is a diagram  300  illustrating a lighting system having three (3) LED dice connected in series via a metal trace in accordance with an aspect of the present invention. Diagram  300  includes an LED array, a substrate  108 , a patterned dielectric layer  106 , and a metal trace  118 . LED dice  110 - 114  coupled to terminals or pads  102 - 104  using bond wires  320 - 330 . The LED array includes three (3) LED dice  110 - 114 , wherein LED dice  110 - 114  are connected in series using metal trace  118 . 
     Referring back to  FIG. 3 , a first terminal of LED die  110  is connected to a first terminal of power source  102  via bond wire  330  and a second terminal of LED die  110  is connected to a first terminal of LED die  114  via bond wire  328 . A second terminal of LED die  114  is connected to metal trace  118  via bond wire  326 . A first terminal of LED die  112  is connected to metal trace  118  via bond wire  322  and a second terminal of LED die  112  is connected to a second terminal of power source  104  via bond wire  320 . Note that the first terminal of power source  102  can be the positive potential of a power supply and the second terminal of power source  104  can be negative potential of a power supply. Diagram  300  illustrates the LED array containing one (1) string of LED dice connected in series. 
       FIG. 4  is a diagram  400  illustrating a lighting system having four (4) LED dice  110 - 116  connected in series via a Z-shaped metal trace in accordance with an aspect of the present invention. Diagram  400  includes an LED array, a substrate  408 , and a metal trace  418  wherein metal trace  418  is in a Z shape. LED dice  110 - 114  are coupled to terminals or pads  102 - 104  using bond wires  420 - 430 . The LED array includes four (4) LED dice  110 - 116 , wherein LED dice  110 - 116  are connected in series connection using metal trace  418 . 
     Referring back to  FIG. 4 , a first terminal of LED die  110  is connected to metal trace  418  via bond wire  424  and a second terminal of LED die  110  is connected to a first terminal of LED die  116  via bond wire  430 . While a second terminal of LED die  116  is connected to a first terminal of power source  104  via bond wire  428 , a second terminal of LED die  114  is connected to metal trace  418  via bond wire  426 . A first terminal of LED  114  is connected to a second terminal of LED die  112  via bond wire  422 , and a first terminal of LED die  112  is connected to a second terminal of power source  102  via bond wire  420 . Note that the first terminal of power source  102  can be the positive potential of a power supply and the second terminal of power source  104  can be negative potential of a power supply. Diagram  400  illustrates an LED array containing one (1) LED string of four (4) LED dice  110 - 116  connected in series using a Z-shaped metal trace. 
     In one aspect, adjacent dice in each row of a matrix or array are directly connected by bond wires between n pad(s) of one die and p pad(s) of adjacent die in series. Dice between different rows are electrically connected in series with bond wire(s) to a conductive metal trace disposed over a substrate. In an alternative aspect, adjacent dice in each column of a matrix or array are directly connected by bond wires between n pad(s) of one die and p pad(s) of adjacent die in series. The dice between different columns are electrically connected in series by bond wire(s) via a conductive metal trace situated over the substrate. It should be noted that an independent conductive metal trace situated between each row and column of LED dice organized in array can provide reconfiguring LED die connections such as in series, parallel, and/or a combination of series and parallel. 
     An advantage of using a Z-shaped metal trace is to provide connection pad as well as render shorter bond wires to achieve reconfigurable interconnections. Note that LED dice connected in series produce more flux for a fixed total drive current than the same number of LED dice in parallel or in series/parallel strings. It is particularly advantageous since power supplies with high current and low voltage are more expensive than those with lower current and high voltage. 
       FIG. 5  is a diagram  550  illustrating a lighting system having multiple LED dice connected in series using a straight metal trace in accordance with an aspect of the present invention. Diagram  550  includes an LED array, a substrate  408 , and a metal trace  518  wherein metal trace  518  is formed in an I shape or a straight line. LED dice  110 - 116  are coupled to terminals or pads  102 - 104  using bond wires  520 - 530 . The LED array includes four (4) LED dice  110 - 116 , wherein LED dice  110 - 116  are connected in series using metal trace  518 . 
     Referring back to  FIG. 5 , a first terminal of LED die  110  is connected to metal trace  518  via bond wire  524  and a second terminal of LED die  110  is connected to a first terminal of LED die  116  via bond wire  530 . While a second terminal of LED die  116  is connected to a first terminal of power source  104  via bond wire  528 , a second terminal of LED die  114  is connected to metal trace  518  via bond wire  526 . A first terminal of LED  114  is connected to a second terminal of LED die  112  via bond wire  522 , and a first terminal of LED die  112  is connected to a second terminal of power source  102  via bond wire  520 . Diagram  550  illustrates an LED array containing one (1) string of LED dice  110 - 116  using an I-shaped metal trace. 
     The first terminal of power source  104 , in one aspect, is a substrate metallization that is connected to a positive (+) terminal of LED array. The second terminal of power source  102 , on the other hand, is a substrate metallization that is connected to a negative (−) terminal of LED array. The perimeter of cavity  540  may be filled with silicone and/or phosphor encapsulation. An advantage of using an I-shaped metal trace is to provide flexible connecting pad for bond wires to achieve reconfigurable connections. 
       FIG. 6A  is a diagram  650  illustrating an alternative metal trace configurations used in an LED light in accordance with an aspect of the present invention. Diagram  650  includes an LED array, an H-shaped metal trace  680 , and electrical terminals  682 - 684 , wherein electrical terminals  682 - 684  are connected to positive and negative power supply. The LED array, in one aspect, includes nine (9) LED dice  660 - 676  capable of converting electrical energy to optical light. H-shaped metal trace  680 , in one aspect, is used for connecting pads for bond wires to provide flexible reconfigurations in connectivity. 
       FIG. 6B  is a diagram  690  illustrating an alternative exemplary connection reconfiguration of an LED lighting device having metal traces situated every other column within an LED array in accordance with an aspect of the present invention. Diagram  690  includes an LED array and I-shaped metal traces  692  wherein the LED array includes x rows by y columns (“X×Y”) of LED dice. I-shaped metal traces  692  are used to facilitate flexible connectivity to generate different LED dice connecting configurations in accordance with one or more specifications. 
       FIG. 7A  illustrates images showing two LED lighting devices capable of reconfiguring connections using metal traces in accordance with an aspect of the present invention. Image  750  shows an LED lighting device including an LED array and an S-shaped metal trace  760 , wherein the LED array further includes four (4) LED dice  752 - 758 . In one aspect, the LED lighting device illustrated in image  750  has similar configuration as the device illustrated in  FIG. 1 . The lighting device uses metal trace  760  to form two (2) strings of LED dice in parallel wherein each string includes two LED dice. 
     Image  770  shows an LED lighting device including an LED array and an S-shaped metal trace  780 , wherein the LED array further includes three (3) LED dice  772 - 776 . In one aspect, lighting device illustrated in image  770  has similar configuration as the device illustrated in  FIG. 2 . The lighting device uses metal trace  780  to form three (3) strings of LED dice in parallel wherein each string includes one (1) LED die. 
       FIG. 7B  illustrates images showing two LED lighting devices capable of reconfiguring alternative connections using metal traces in accordance with an aspect of the present invention. Image  786  shows an LED lighting device including an array of four LED dice configured in four (4) strings of LED dice in parallel wherein each string includes one LED die. Image  788  shows an LED lighting device including an array of four LED dice configured in one (1) string of four (4) LED dice connected in series. 
       FIG. 7C  illustrates images showing two LED lighting devices capable of reconfiguring alternative connections using metal traces in accordance with an aspect of the present invention. Image  790  shows an LED lighting device including an array of four (4) LED dice configured in one (1) string of four (4) LED dice connected in series using an L shaped metal trace  792 . Image  796  shows an LED lighting device including an array of three (3) LED dice configured in one (1) string of three (3) LED dice connected in series. 
       FIG. 8A  is a diagram  850  illustrating an exploded view of a lighting system having an LED array using a metal trace for providing flexible LED connections in accordance with an aspect of the present invention. Diagram  850  includes a substrate or base layer  862 , a patterned dielectric layer  860 , a metal layer  858 , a metal trace  864 , a solder mask layer  856 , a disk  854  including encapsulant, and a cavity ring  852 . Metal layer  858  further includes a first terminal  864  and a second terminal  866  wherein metal layer  858  is a conductive layer, which can be made of copper, nickel, aluminum, gold or a combination of conductive alloy. First and second terminals  864 - 866  are configured to connect to negative and positive power terminals  868 - 870 , respectively. It should be noted that the components illustrated in diagram  850  can be pre-fabricated, and the connecting configuration in the LED array can be subsequently configured according to the specification using bond wires. Note that the underlying concept of the exemplary aspect(s) of the present invention would not change if one or more components (or layers) were added to or removed from diagram  850 . 
       FIG. 8B  illustrates images of LED lighting assembly having an LED array and metal trace for facilitating flexible LED connections in accordance with an aspect of the present invention. Image  870  shows a top view of an LED lighting assembly having an LED array and a metal trace  882 , wherein the LED array includes four (4) LED dice  874 - 880 . Image  890  illustrates an isometric view of the LED lighting assembly shown in image  870 . In one aspect, the connection configuration of LED dice  874 - 880  can be adjusted or reconfigured using bond wires via metal trace  882 . 
     The exemplary aspect of the present invention includes various processing steps, which will be described below. The steps of the aspect may be embodied in machine or computer executable instructions. The instructions can be used to cause a general purpose or special purpose system, which is programmed with the instructions, to perform the steps of the exemplary aspect of the present invention. Alternatively, the steps of the exemplary aspect of the present invention may be performed by specific hardware components that contain hard-wired logic for performing the steps, or by any combination of programmed computer components and custom hardware components. 
       FIG. 9  is a flowchart  950  illustrating a process of fabricating a lighting device having multiple LED dice and a metal trace for reconfigurable connections in accordance with an aspect of the present invention. At block  952 , a process of fabricating an LED system deposits a dielectric layer over a base layer to provide electric insulation. The base layer is a substrate that can be made of electric conductive material or dielectric material. 
     At block  954 , a metal trace having a predefined shape is overlaid on the dielectric layer to provide electrical connections. In one aspect, the process is capable of disposing an S-shaped metal plate over the dielectric layer. In another aspect, the process is able to dispose a Z-shaped metal plate over the dielectric layer for facilitating one or more bond wire connections. In yet another aspect, the process disposes a straight metal strip over the dielectric layer to facilitate one or more bond wire connections. 
     At block  956 , a process deposits multiple LED dice in an array formation over a base layer. In one aspect, the array formation includes four (4) LED dice. In an alternative aspect, the array formation includes three (3) LED dice. 
     At block  958 , the process deposits LED dice in an array formation over the base layer, wherein the depositing process is able to dispose LED dice in such a way that allows the metal trace to travel through the array of LED dice. In one aspect, upon depositing an electric conductive metal layer over the dielectric layer for providing electrical power, the process connects at least a portion of the LED dice in series configurations utilizing bond wires and the metal trace. While at least a portion of the LED dice is connected in parallel connections utilizing bond wires and the metal trace, the process is capable of configuring at least a portion of the LED dice in a combination of series connections and parallel connections via utilization of bond wires and the metal trace. 
     At block  960 , the process, in one embodiment, encloses the LED device with incapsulant and a cavity ring. Encapsulant can be a type of adhesive or non-adhesive material capable of sealing a component or components. Deposing a disk together with a cavity ring, in one example, can be the final processing stage for fabricating the LED device. 
     Having briefly described aspects of lighting assemblies capable of reconfiguring connections of LED dice using a metal trace in which the present invention operates, the following figures illustrate exemplary process and/or method to fabricate and package LED dies, chips, device, and/or fixtures. 
       FIG. 10  is a conceptual cross-sectional view illustrating an exemplary fabrication process of an LED or LED devices. An LED is a semiconductor material impregnated, or doped, with impurities. These impurities add “electrons” or “holes” to the semiconductor, which can move in the material relatively freely. Depending on the kind of impurity, a doped region of the semiconductor can have predominantly electrons or holes, and is referred respectively as n-type or p-type semiconductor regions. Referring to  FIG. 10 , the LED  500  includes an n-type semiconductor region  504  and a p-type semiconductor region  508 . A reverse electric field is created at the junction between the two regions, which cause the electrons and holes to move away from the junction to form an active region  506 . When a forward voltage sufficient to overcome the reverse electric field is applied across the p-n junction through a pair of electrodes  510 ,  512 , electrons and holes are forced into the active region  506  and recombine. When electrons recombine with holes, they fall to lower energy levels and release energy in the form of light. 
     In this example, the n-type semiconductor region  504  is formed on a substrate  502  and the p-type semiconductor region  508  is formed on the active layer  506 , however, the regions may be reversed. That is, the p-type semiconductor region  508  may be formed on the substrate  502  and the n-type semiconductor region  504  may formed on the active layer  506 . As those skilled in the art will readily appreciate, the various concepts described throughout this disclosure may be extended to any suitable layered structure. Additional layers or regions (not shown) may also be included in the LED  500 , including but not limited to buffer, nucleation, contact and current spreading layers or regions, as well as light extraction layers. 
     The p-type semiconductor region  508  is exposed at the top surface, and therefore, the p-type electrode  512  may be readily formed thereon. However, the n-type semiconductor region  504  is buried beneath the p-type semiconductor layer  508  and the active layer  506 . Accordingly, to form the n-type electrode  510  on the n-type semiconductor region  504 , a cutout area or “mesa” is formed by removing a portion of the active layer  506  and the p-type semiconductor region  508  by means well known in the art to expose the n-type semiconductor layer  504  there beneath. After this portion is removed, the n-type electrode  510  may be formed. 
       FIG. 11  is a conceptual cross-sectional view illustrating an example of an LED with a phosphor layer. In this example, a phosphor layer  602  is formed on the top surface of the LED  500  by means well known in the art. The phosphor layer  602  converts a portion of the light emitted by the LED  500  to light having a different spectrum. A white LED light source can be constructed by using an LED that emits light in the blue region of the spectrum and a phosphor that converts blue light to yellow light. A white light source is well suited as a replacement lamp for conventional luminaries; however, the invention may be practiced with other LED and phosphor combinations to produce different color lights. The phosphor layer  602  may include, by way of example, phosphor particles suspended in a carrier or be constructed from a soluble phosphor that is dissolved in the carrier. 
     In a configuration of LED luminaries, an LED array may be used to provide increased luminance.  FIG. 12A  is a conceptual top view illustrating an example of an LED array, and  FIG. 12B  is a conceptual cross-sectional view of the LED array of  FIG. 12A . In this example, a number of phosphor-coated LEDs  600  may be formed on a substrate  702 . The bond wires (not shown) extending from the LEDs  600  may be connected to traces (not shown) on the surface of the substrate  702 , which connect the LEDs  600  in a parallel and/or series fashion. In some embodiments, the LEDs  600  may be connected in parallel streams of series LEDs with a current limiting resistor (not shown) in each stream. The substrate  702  may be any suitable material that can provide support to the LEDs  600  and can be mounted within a light fixture (not shown). 
       FIG. 13A  is a conceptual top view illustrating an example of an alternative configuration of an LED array, and  FIG. 13B  is a conceptual cross-sectional view of the LED array of  FIG. 13A . In a manner similar to that described in connection with  FIGS. 12A and 12B , a substrate  702  designed for mounting in a light fixture (not shown) may be used to support an array of LEDs  500 . However, in this configuration, a phosphor layer is not formed on each individual LED. Instead, phosphor  806  is deposited within a cavity  802  bounded by an annular ring  804  that extends circumferentially around the outer surface of the substrate  702 . The annular ring  804  may be formed by boring a cylindrical hole in a material that forms the substrate  702 . Alternatively, the substrate  702  and the annular ring  804  may be formed with a suitable mold, or the annular ring  804  may be formed separately from the substrate  702  and attached to the substrate using an adhesive or other suitable means. In the latter configuration, the annular ring  804  is generally attached to the substrate  702  before the LEDs  500 , however, in some configurations, the LEDs may be attached first. Once the LEDs  500  and the annular ring  804  are attached to the substrate  702 , a suspension of phosphor particles in a carrier may be introduced into the cavity  802 . The carrier material may be an epoxy or silicone; however, carriers based on other materials may also be used. The carrier material may be cured to produce a solid material in which the phosphor particles are immobilized. 
       FIG. 14  shows exemplary devices including LEDs or LED devices using metal traces in accordance with aspects of the present invention. The devices  900  include a lamp  902 , an illumination device  904 , and a street light  906 . Each of the devices shown in  FIG. 14  includes at least an LED or an LED device using metal traces as described herein. For example, lamp  902  includes a package  916  and an LED  908 , in which LED  908  employs one or more metal traces to provide flexible connections. Lamp  902  may be used for any type of general illumination. For example, lamp  902  may be used in an automobile headlamp, street light, overhead light, or in any other general illumination application. Illumination device  904  includes a power source  910  that is electrically coupled to a lamp  912 , which may be configured as lamp  902 . In an aspect, power source  910  may be batteries or any other suitable type of power source, such as a solar cell. Street light  906  includes a power source connected to a lamp  914 , which may be configured as lamp  902 . It should be noted that aspects of the LED described herein are suitable for use with virtually any type of LED assembly, which in turn may be used in any type of illumination device and are not limited to the devices shown in  FIG. 14 . 
     The various aspects of this disclosure are provided to enable one of ordinary skill in the art to practice the present invention. Various modifications to aspects presented throughout this disclosure will be readily apparent to those skilled in the art, and the concepts disclosed herein may be extended to other LED lamp configurations regardless of the shape or diameter of the glass enclosure and the base and the arrangement of electrical contacts on the lamp. Thus, the claims are not intended to be limited to the various aspects of this disclosure, but are to be accorded the full scope consistent with the language of the claims. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. §112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.”