Patent Publication Number: US-2015069450-A1

Title: Light emitting module

Description:
RELATED APPLICATIONS 
     This application claims priority to Taiwan Application Serial Number 102132620, filed Sep. 10, 2013, which is herein incorporated by reference. 
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to a light emitting module, 
     2. Description of Related Art 
     In the production a conventional light emitting module, a surface mounting process of surface mounted technology (STM) is performed to bond the light emitting diode on the substrate using solder. However, during the surface mounting process, instability occurs because different production machines have different tolerances, or various components have different temperature performances. As such, solders at different places may be electrically connected with each other to cause a short circuit. Further, in a next curing process after the surface mounting process, the solders at different places are possibly molten again under a high temperature, which also causes the respective solders to be electrically connected with each other. A general solution is to use a metal with higher melting temperature as the solder. However, when the melting point becomes higher, the processing temperature in the surface mounting process must increase with the higher melting temperature of the materials used as the solders. Consequently, more energy is consumed, much less the higher damage risks of the components during the surface mounting process. 
     SUMMARY 
     The present disclosure provides a light emitting module including a substrate, a light emitting diode, a first adhesive glue, and a second adhesive glue. The substrate has a first electrode and a second electrode. The light emitting diode is disposed on the substrate and has a third electrode and a fourth electrode. The first adhesive glue is located between the first electrode and the second electrode so as to enable the first electrode to be electrically connected to the second electrode. The first adhesive glue includes a first conductive body and a first insulation body surrounding the first conductive body. The second adhesive glue is located between the third electrode and the fourth electrode so as to make the third electrode be electrically connected to the fourth electrode. The second adhesive glue includes a second conductive body and a second insulation body surrounding the second conductive body, and thus the first adhesive glue and the second adhesive glue are not electrically connected to each other. 
     In an embodiment of the present disclosure, the light emitting diode is a light emitting diode package. The light emitting diode package includes a lead frame, a carrier, a light emitting diode chip, and a first encapsulant. The carrier covers a part of the lead frame and exposes a bonding zone of the lead frame, the third electrode, and the fourth electrode. The light emitting diode chip is disposed on the bonding zone and electrically connected to the third electrode and the fourth electrode. The first encapsulant is filled into the bonding zone of the carrier and covers the light emitting diode chip. 
     In an embodiment of the present disclosure, the light emitting diode is a light emitting diode chip. 
     In an embodiment of the present disclosure, the light emitting module further includes a second encapsulant covering the light emitting diode chip. 
     In an embodiment of the present disclosure, the light emitting diode chip is a flip chip. 
     In an embodiment of the present disclosure, the first conductive body and the second conductive body are tin, copper-tin alloy, gold-tin alloy, or the combination thereof. 
     In an embodiment of the present disclosure, the first insulation body and the second insulation body include silicone, epoxy, acrylate, acrylic, or the combination thereof. 
     The present disclosure further provides another light emitting module including a lead frame, a carrier, a light emitting diode chip, a first adhesive glue, and a second adhesive glue. The lead frame includes a predetermined bonding zone. The bonding zone includes a first electrode and a second electrode not electrically connected to each other. The carrier covers a part of the lead frame and exposes the bonding zone of the lead frame, the first electrode, and the second electrode. The light emitting diode chip is disposed on the bonding zone and has a third electrode and a fourth electrode. The first adhesive glue is located between the first electrode and the second electrode so as to enable the first electrode to be electrically connected to the second electrode. The first adhesive glue includes a first conductive body and a first insulation body surrounding the first conductive body. The second adhesive glue is located between the third electrode and the fourth electrode so as to enable the third electrode to be electrically connected to the fourth electrode. The second adhesive glue includes a second conductive body and a second insulation body surrounding the second conductive body, and thus the first adhesive glue and the second adhesive glue are not electrically connected to each other. 
     In an embodiment of the present disclosure, the light emitting module further includes an encapsulant covering the light emitting diode chip. 
     In an embodiment of the present disclosure, the light emitting diode chip is a flip chip. 
     In an embodiment of the present disclosure, the first conductive body and the second conductive body are made of tin, copper-tin alloy, gold-tin alloy, or the combination thereof. 
     In an embodiment of the present disclosure, the first insulation body and the second insulation body include silicone, epoxy, acrylate, acrylic, or the combination thereof. 
     Accordingly, the light emitting module of the present disclosure can solve a short circuit problem caused by solders at different places of a conventional light emitting module that are electrically connected to each other during the manufacturing processes. The present disclosure replaces the conventional solder into the composite glue having a conductive body and an insulation body. 
     The composite glue is electrically conductive and has the function of isolating from another composite glue, so that the short circuit problem during the manufacturing processes can be solved. The present disclosure effectively solves the short circuit problem when the light emitting diode package is electrically connected to the substrate. The present disclosure can also prevent the short circuit problem when the light emitting diode chip is electrically connected to the substrate directly. The present disclosure can also improve the short circuit problem within the light emitting diode package. Thus, the production yield of the light emitting module can be improved. 
     It is to be understood that both the foregoing general description and the following detailed description are by examples, and are intended to provide further explanation of the disclosure as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The disclosure can be more fully understood by reading the following detailed description of the embodiment, with reference made to the accompanying drawings as follows: 
         FIG. 1  is a cross-sectional view of a light emitting module according to an embodiment of the present disclosure; 
         FIG. 2  is a cross-sectional view of a light emitting module according to another embodiment of the present disclosure; 
         FIG. 3  is a cross-sectional view of a light emitting module according to another embodiment of the present disclosure; 
         FIG. 4  is a cross-sectional view of a composite glue in  FIG. 3  along line  4 - 4 ′ before curing; and 
         FIG. 5  is a cross-sectional view of the composite glue in  FIG. 3  along line  4 - 4  after curing. 
     
    
    
     DETAILED DESCRIPTION 
     Reference will now be made in detail to the present embodiments of the disclosure, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts. 
     In order to solve a problem that solders of a conventional light emitting module may cause a short circuit, the present disclosure provides a light emitting module to improve the problem.  FIG. 1  is a cross-sectional view of a light emitting module according to an embodiment of the present disclosure. The light emitting module  100   a  has a substrate  140 , a light emitting diode  200 , a first adhesive glue  120 , and a second adhesive glue  130 . In this embodiment of the present disclosure, the light emitting diode  200  is a light emitting diode package. The substrate  140  has a first electrode  142  and a second electrode  144 . The light emitting diode package (i.e., the light emitting diode  200 ) is disposed on the substrate  140  and has a third electrode  112 , and a fourth electrode  114 . The first adhesive glue  120  is located between the first electrode  142  and the second electrode  144  so as to make the first electrode  142  be connected to the second electrode  144 . The first adhesive glue  120  includes a first conductive body  122  and a first insulation body  124  surrounding the first conductive body  122 . The second adhesive glue  130  is located between the third electrode  112  and the fourth electrode  114 , so as to enable the third electrode  112  to be electrically connected to the fourth electrode  114 . The second adhesive glue  130  includes a second conductive body  132  and a second insulation body  134  surrounding the second conductive body  132 , and thus the first adhesive glue  120  and the second adhesive glue  130  are not electrically connected to each other. The light emitting diode package includes a lead frame  220 , a carrier  210 , a light emitting diode chip  320 , and a first encapsulant  400 . The carrier  210  covers a part of the lead frame  220  and exposes a bonding zone  230  of the lead frame  220 , the third electrode  112 , and the fourth electrode  114 . The light emitting diode chip  320  is disposed on the bonding zone  230  and electrically connected to the third electrode  112  and the fourth electrode  114 . The first encapsulant  400  is filled into the bonding zone  230  of the carrier  210  and covers the light emitting diode chip  320 . The first conductive body  122  and the second conductive body  132  are tin, copper-tin alloy, gold-tin alloy, or the combination thereof. The first insulation body  124  and the second insulation body  134  include silicone, epoxy, acrylate, acrylic, or the combination thereof. The present disclosure uses a composite glue in place of the conventional solders in order to rule out the possibility of electrical connection between the solders during manufacturing processes. Thus, the problem of short circuit is solved. 
     People having ordinary skill in the art can make proper modification to the materials of the first conductive body  122 , the second conductive body  132 , the first insulation body  124 , and the second insulation body  134  according to their actual needs. 
       FIG. 2  is a cross-sectional view of a light emitting module according to another embodiment of the present disclosure. The light emitting module  100   b  has a substrate  140 , a light emitting diode  250 , a first adhesive glue  120 , a second adhesive glue  130 , and the second encapsulant  420 . In this embodiment of the present disclosure, the light emitting diode  250  is the light emitting diode chip. The second encapsulant  420  covers the light emitting diode chip (i.e., the light emitting diode  250 ), and the light emitting diode chip is a flip chip. The substrate  140  has a first electrode  142  and a second electrode  144 . The light emitting diode chip is disposed on the substrate  140  and has a third electrode  112 ′, and a fourth electrode  114 . The first adhesive glue  120  is located between the first electrode  142  and the second electrode  144  so as to enable the first electrode  142  to be electrically connected to the second electrode  144 . The first adhesive glue  120  includes a first conductive body  122  and a first insulation body  124  surrounding the first conductive body  122 . The second adhesive glue  130  is located between the third electrode  112 ′ and the fourth electrode  114 ′ so as to enable the third electrode  112  to be electrically connected to the fourth electrode  114 ′. The second adhesive glue  130  includes a second conductive body  132  and a second insulation body  134  surrounding the second conductive body  132 , and thus the first adhesive glue  120  and the second adhesive glue  130  are not electrically connected to each other. The present disclosure uses a composite glue in place of the conventional solders in order to rule out the possibility of electrical, connection between the solders during manufacturing processes. Thus, the problem of short circuit is solved. The first conductive body  122  and the second conductive body  132  are tin, copper-tin alloy, gold-tin alloy, or the combination thereof. The first insulation body  124  and the second insulation body  134  include silicone, epoxy, acrylate, acrylic, or the combination thereof. 
       FIG. 3  is a cross-sectional view of a light emitting module according to another embodiment of the present disclosure. The light emitting module  100   c  has a lead frame  220 , a carrier  210 , a light emitting diode chip  300 , a first adhesive glue  120 , a second adhesive glue  130 , and a encapsulant  440 . The encapsulant  440  covers the light emitting diode chip  300 , and the light emitting diode chip  300  is flip chip. The lead frame  220  includes a predetermined bonding zone  230 . The bonding zone  230  includes a first electrode  142 ′ and a second electrode  144 ′ not electrically connected to each other. The carrier  210  covers a part of the lead frame  220  and exposes the bonding zone  230  of the lead frame  220 , the first electrode  142 ′, and the second electrode  144 ′. The light emitting diode chip  300  is disposed on the bonding zone  230 . The light emitting diode chip  300  has a third electrode  112 ′, and a fourth electrode  114 ′. The first adhesive glue  120  is located between the first electrode  142 ′ and the second electrode  144 ′ to make the first electrode  142 ′ electrically connected to the second electrode  144 ′. The first adhesive glue  120  includes a first conductive body  122  and a first insulation body  124  surrounding the first conductive body  122 . The second adhesive glue  130  is located between the third electrode  112 ′ and the fourth electrode  114 ′ to make the third electrode  112 ′ electrically connected to the fourth electrode  114 ′. The second adhesive glue  130  includes a second conductive body  132  and a second insulation body  134  surrounding the second conductive body  132 , and thus the first adhesive glue  120  and the second adhesive glue  130  are not electrically connected to each other. The present disclosure uses a composite glue in place of the conventional solders in order to rule out the possibility of electrical connection between the solders during manufacturing processes. Thus, the problem of short circuit is solved. The first conductive body  122  and the second conductive body  132  are tin, copper-tin alloy, gold-tin alloy, or the combination thereof. The first insulation body  124  and the second insulation body  134  include silicone, epoxy, acrylate, acrylic, or the combination thereof. 
       FIG. 4  is a cross-sectional view of a composite glue in  FIG. 3  along line  4 - 4 ′ before curing.  FIG. 5  is a cross-sectional view of the composite glue in  FIG. 3  along line  4 - 4 ′ after curing. The composite glue is made of a glue  500 , a first metal  600 , and the second metal  700 . The second metal  700  wraps up the first metal  600  and distributes randomly in the glue  500 . After the composite glue goes through the curing processes, the first metal  600  and the second metal  700  are heated to form an alloy  800 , and the glue  500  wraps up the alloy  800 . The alloy  800  becomes a conductive body, and the glue  500  becomes an insulation body. Because the glue  500  and the alloy  800  have different chemical properties, they do not melt together. In an embodiment of the present disclosure, the first metal  600  is tin, the second metal  700  is copper or gold, and thus the alloy  800  is a copper-tin alloy or a gold-tin alloy. 
     Accordingly, the light emitting module of the present disclosure can solve a short circuit problem caused by solders at different places of a conventional light emitting module that are electrically connected to each other during the manufacturing processes. The present disclosure replaces the conventional solder into the composite glue having a conductive body and an insulation body. The composite glue is electrically conductive and has the function of isolating from another composite glue, so that the short circuit problem during the manufacturing processes can be solved. The present disclosure effectively solves the short circuit problem when the light emitting diode package is electrically connected to the substrate. The present disclosure can also prevent the short circuit problem when the light emitting diode chip is electrically connected to the substrate directly. The present disclosure can also improve the short circuit problem within the light emitting diode package. Thus, the production yield of the light emitting module can be improved. 
     Although the present disclosure has been described in considerable detail with reference to certain embodiments thereof, other embodiments are possible. Therefore, the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein. 
     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present disclosure without departing from the scope or spirit of the disclosure. In view of the foregoing, it is intended that the present disclosure cover modifications and variations of this disclosure provided they fail within the scope of the following claims.