Abstract:
A light-emitting diode device is disclosed. The light-emitting diode device includes a transparent substrate with a first surface, a second surface opposite to the first surface, and a side surface connected to the first surface and the second surface; a first light-emitting structure; a second light-emitting structure; a connecting layer, connected to the first light-emitting structure and the second light-emitting structure; a circuit arranged between the transparent substrate and the first light-emitting structure, and having a portion formed on the first surface without extending to the second surface; and a structure with diffusers, covering the first light-emitting structure and the second light-emitting structure on the first surface without crossing over the side surface.

Description:
REFERENCE TO RELATED APPLICATION 
       [0001]    This application is a continuation application of U.S. patent application Ser. No. 13/282,317, filed on Oct. 26, 2011, which claims the right of priority based on TW application Ser. No. 096143129, filed Nov. 13, 2007, entitled “LIGHT-EMITTING DEVICE PACKAGE”, U.S. application Ser. No. 12/292,161, filed Nov. 13, 2008, entitled “LIGHT-EMITTING DEVICE PACKAGE”, and the contents of which are incorporated herein by reference. 
     
    
     BACKGROUND 
       [0002]    1. Technical Field 
         [0003]    A light-emitting diode device is disclosed. 
         [0004]    2. Description of the Related Art 
         [0005]    Generally, light-emitting diodes (LEDs) having transparent substrates are divided into face-up type and flip-chip type. For the face-up type, the light-emitting diodes are attached to carriers by gels or metals; for flip-chip type, the light-emitting diodes are attached to carriers by metals or solders with the attached surface as the light extraction surface of the light-emitting diode or the surface parallel to it. Because the light extracted from the light-emitting layer of the light-emitting diodes are 360 degree, the light emitting downward is generally reflected to the front of the light extraction side by the reflecting layers or extracted from the transparent substrates. The thickness of the transparent substrate should be properly adjusted so that the brightness of the light extraction is acceptable. Besides, when the size of the light-emitting diodes is larger, there are more reflected light passing through the multi-quantum well (MQW) in the light-emitting layer. The light efficiency is reduced because of light absorption. 
         [0006]      FIG. 1  shows a schematic illustration of conventional light-emitting diode device. As shown in  FIG. 1 , a light-emitting diode chip  100  is attached to a carrier  3  with an attached surface  1  which is parallel to the front light extraction surface  4  of the light-emitting diode chip  100 . The light emitted downward is reflected to the front light extraction surface  4  or the lateral light extraction surface  5  by the reflector  2 . The disadvantage of this device is when the size of the light-emitting diode chip is larger, there are more reflected light passing through the multi-quantum well (MQW) in the light-emitting layer. The light efficiency is reduced because of light absorption. 
       SUMMARY 
       [0007]    A light-emitting diode device is disclosed. The light-emitting diode device includes a transparent substrate with a first surface, a second surface opposite to the first surface, and a side surface connected to the first surface and the second surface; a first light-emitting structure; a second light-emitting structure; a connecting layer, connected to the first light-emitting structure and the second light-emitting structure; a circuit arranged between the transparent substrate and the first light-emitting structure, and having a portion formed on the first surface without extending to the second surface; and a structure with diffusers, covering the first light-emitting structure and the second light-emitting structure on the first surface without crossing over the side surface. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The accompanying drawings are included to provide easy understanding of the invention, and are incorporated herein and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to illustrate the principles of the invention. 
           [0009]      FIG. 1  is an illustration of conventional light-emitting diode device. 
           [0010]      FIG. 2  is a lateral view of the light-emitting structure of the present invention. 
           [0011]      FIG. 3  is a lateral view of the light-emitting structure of another embodiment of the present invention. 
           [0012]      FIG. 4  is a lateral view of the light-emitting device of the present invention. 
           [0013]      FIG. 5  is a lateral view of the light-emitting device of another embodiment of the present invention. 
           [0014]      FIG. 6  is a lateral view of the light-emitting diode device of the present invention. 
           [0015]      FIG. 7  is a lateral view of the light-emitting diode device of another embodiment of the present invention. 
           [0016]      FIG. 8  is a lateral view of the light-emitting diode device of another embodiment of the present invention. 
           [0017]      FIG. 9  is a lateral view of the light-emitting diode device of another embodiment of the present invention. 
           [0018]      FIG. 10  is an illustration of the backlight module of the liquid crystal display device of the present invention. 
           [0019]      FIG. 11  is an illustration of another backlight module of the liquid crystal display device of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0020]    Reference is made in detail to the preferred embodiments of the present invention, 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. 
         [0021]      FIGS. 2 and 3  show the light-emitting structures in accordance with one embodiment of the present application. Referring to  FIG. 2 , a structure of a light-emitting diode chip  200  includes an epitaxial structure  202  formed on the growth substrate  201  by metal-organic chemical vapor deposition (MOCVD) process or an epitaxial structure formed on the supporting substrate by a bonding process, wherein the epitaxial structure having a first conductivity type semiconductor layer  202   a , an active layer  202   b , and a second conductivity type semiconductor layer  202   c . A first electrode  203  and a second electrode  204  are disposed on the epitaxial structure  202  to form a horizontal structure of the light-emitting diode chip  200 . 
         [0022]    The material of the growth substrate can be transparent material such as Sapphire, ZnO, or AlN. The growth substrate can also be high thermal-dissipative materials such as diamond like carbon (DLC), graphite, Si, SiC, GaP, GaAs, or LiAlO 2 . 
         [0023]    Referring to  FIG. 3 , a structure of a light-emitting diode chip  300  includes an epitaxial structure  302  formed on the growth substrate  301  by metal-organic chemical vapor deposition (MOCVD) process or an epitaxial structure formed on the supporting substrate by a bonding process, wherein the epitaxial structure having a first conductivity type semiconductor layer  302   a , an active layer  302   b , and a second conductivity type semiconductor layer  302   c . A first electrode  303  is formed on the first side of the epitaxial structure  302  and the second electrode  304  is formed on the second side opposite to first side of the epitaxial structure  302  to form a vertical structure of the light-emitting diode chip  300 . 
         [0024]    The material of the support substrate can be transparent material or electrically insulating material such as sapphire, diamond, glass, epoxy, quartz, acrylate, ZnO, or AlN. The support substrate can also be high thermal-dissipative materials or reflective materials such as Cu, Al, Mo, Cu—Sn, Cu—Zn, Cu—Cd, Ni—Sn, Ni—Co, Au alloy, diamond like carbon (DLC), graphite, carbon fiber, metal matrix composite (MMC), ceramic matrix composite (CMC), polymer matrix composite (PMC), Si, IP, ZnSe, GaAs, SiC, GaP, GaAsP, ZnSe, InP, LiGaO 2 , or LiAlO 2 . 
         [0025]      FIG. 4  is an illustration of the light-emitting device  400  in accordance with one embodiment of the present application. A structure of the light-emitting diode chip such as the light-emitting diode chip  200  or  300  is attached to a first surface  404   a  of the transparent substrate  404  to form a light-emitting device  400 . The structure of the light-emitting diode chip  200  includes a growth substrate  201 , an epitaxial structure  202  formed on the growth substrate  201  wherein the epitaxial structure having a first conductivity type semiconductor layer  202   a , an active layer  202   b , and a second conductivity type semiconductor layer  202   c ; a first electrode  203  and a second electrode  204  formed on the epitaxial structure  202 . 
         [0026]    The material of the transparent substrate can be sapphire, diamond, glass, epoxy, quartz, acrylate, ZnO, AlN, or SiC. 
         [0027]      FIG. 5  is an illustration of the light-emitting device  500  in accordance with one embodiment of the present application. A structure of the light-emitting diode chip such as light-emitting diode chip  200  or  300  is attached to a transparent substrate  504  containing phosphor materials to form a light-emitting device  500 . The structure of the light-emitting diode chip  200 , includes a growth substrate  201 , an epitaxial structure  202  formed on the growth substrate  201  wherein the epitaxial structure having a first conductivity type semiconductor layer  202   a , an active layer  202   b , and a second conductivity type semiconductor layer  202   c ; a first electrode  203  and a second electrode  204  formed on the epitaxial structure  202 . Following, a phosphor layer  505  is positioned over and around the structure of the light-emitting diode chip  200  to form a light-emitting device  500 . 
         [0028]    As shown in  FIG. 4  and  FIG. 5 , the structure of the light-emitting diode chip  200  or  300  can be attached to the transparent substrate  404  or  504  by a connecting layer (not shown in  FIG. 4  and  FIG. 5 ). The material of the connecting layer can be an insulating material such as polyimide, BCB, PFCB, MgO, SUB, epoxy, acrylic resin, COC, PMMA, PET, PC, polyetherimide, fluorocarbon polymer, silicone, glass, Al 2 O 3 , SiO x , TiO 2 , SiN x , SOG, or other organic adhesive material. The material of the connecting layer can also be a conductive material such as ITO, InO, SnO, CTO, ATO, AZO, ZTO, IZO, Ta 2 O 5 , DLC, Cu, Al, Sn, Au, Ag, Ti, Ni, Pb, Cr, Ag—Ti, Cu—Sn, Cu—Zn, Cu—Cd, Sn—Pb—Sb, Sn—Pb—Zn, Ni—Sn, Ni—Co, or Au alloy, and so on. The material of the connecting layer can also be a semiconductor layer such as ZnO, AlGaAs, GaN, GaP, GaAs, GaAsP, and so on. 
         [0029]      FIG. 6  is a lateral view of the light-emitting diode device  10  in accordance with one embodiment of the present application. The aforementioned structures of light-emitting device  400  or  500  are applicable to the light-emitting diode device  10  shown in the embodiments of the present application, and the light-emitting device  400  is chosen to describe the embodiments to avoid repeating description. Referring to  FIG. 6 , a carrier  601  having a reflective inside wall  602  is provided wherein the carrier can be a printed circuit board, a ceramics substrate, or a silicon substrate. A transparent substrate  404  of the light-emitting device  400  is attached to a platform  603  of the carrier  601  by an adhering material, wherein the first surface  404   a  of the transparent substrate  404  and its parallel surface (the second surface  404   b ) are disposed on the platform  603 . In a preferred embodiment, the transparent substrate  404  is approximately perpendicular to the platform  603 . In addition, the p and n electrode of the light-emitting device is electrically connected to a p electrode  606  and an n electrode  607  of the carrier respectively to form a light-emitting diode device  10 . The light emitted from the active layer of the light-emitting device  400  is omnidirectional. The light emitted to the first surface  404   a  of the transparent substrate  404  is passed through the transparent substrate  404 , and emitted from the second surface  404   b  of the transparent substrate  404 . The light is reflected from the reflective inside wall  602  of the carrier and leaves the light-emitting diode device  10 . Besides, a lens  604  can be positioned over the light-emitting diode device  10  to increase the light efficiency. 
         [0030]      FIG. 7  is a lateral view of the light-emitting diode device  20  of the second embodiment of the present invention. A transparent substrate  404  of a light-emitting device  400  is attached to a carrier  701  having a reflector  703  by an adhering material  704  wherein the carrier is a printed circuit board, a ceramics substrate, or a silicon substrate. In a preferred embodiment, the transparent substrate  404  is approximately perpendicular to the carrier  701 . The p and n electrode of the light-emitting device  400  is electrically connected to the p and n electrode of the carrier respectively. The diffusers  702  are filled in the light-emitting diode device  20  to scatter the light emitted from the light-emitting device  400 . The light (as the arrows indicating in  FIG. 7 ) passes through the transparent substrate  404  and is emitted out from the second surface  404   b  to form a lateral light-emitting diode device  20 . 
         [0031]      FIG. 8  is a lateral view of the light-emitting diode device  30  of another embodiment of the present application. A multi-LED structure  800  is formed by bonding two horizontal structures of the light-emitting diode chips  200  and  200 ′ back to back through a connecting layer (not shown in the figure). The structure of the light-emitting diode chip  200  can comprise GaN series material which emits blue light and the structure of the light-emitting diode chip  200 ′ can comprise AlGaInP series material which emits red light. Besides, an intermediate substrate  801  can be formed between the structures of the light-emitting diode chips  200  and  200 ′. The intermediate substrate  801  can be a transparent growth substrate of the blue light-emitting diode chip  200 . Besides, a mirror (not shown in the figure) can be further formed at one side of the intermediate substrate  801  to enhance the light extraction efficiency of the light-emitting diode device  30 . 
         [0032]    The material of the connecting layer can be insulating material such as polyimide, BCB, PFCB, MgO, SUB, epoxy, Acrylic Resin, COC, PMMA, PET, PC, polyetherimide, fluorocarbon polymer, silicone, glass, Al 2 O 3 , SiO x , TiO 2 , SiN x , SOG, or other organic adhesive material. The material of the connecting layer can also be a conductive material such as ITO, InO, SnO, CTO, ATO, AZO, ZTO, IZO, Ta 2 O 5 , DLC, Cu, Al, Sn, Au, Ag, Ti, Ni, Pb, Cr, Ag—Ti, Cu—Sn, Cu—Zn, Cu—Cd, Sn—Pb—Sb, Sn—Pb—Zn, Ni—Sn, Ni—Co, or Au alloy, and so on. The material of the connecting layer can also be a semiconductor layer such as ZnO, AlGaAs, GaN, GaP, GaAs, GaAsP, and so on. 
         [0033]    The multi-LED structure  800  is attached to the transparent substrate  404  and electrically connected to the circuit (not shown in the figure) on the transparent substrate  404  through directly bonding, solder bonding, and/or wire bonding. The transparent substrate  404  of the light-emitting device  800  is further attached to a carrier  701  having a reflective surface  703  by an adhering material  704  wherein the carrier  701  is a printed circuit board, a ceramics substrate, or a silicon substrate. In a preferred embodiment, the transparent substrate  404  is approximately perpendicular to the carrier  701 . The circuit (not shown in the figure) of the transparent substrate  404  is electrically connected to a first electrode (ex. p electrode)  701   a  and a second electrode (ex. n electrode)  701   b  of the carrier  701  respectively. Diffusers  702  are filled in the light-emitting diode device  30  to scatter the light emitted from the light-emitting device  800 . The light (as the arrows indicating in  FIG. 8 ) passes through the transparent substrate  404  and is emitted out from the second surface  404   b . In this embodiment, the structure of the light-emitting diode chip  200  and the structure of the light-emitting diode chip  200 ′ are electrically connected to each other in parallel. 
         [0034]      FIG. 9  is a lateral view of the light-emitting diode device  40  of one embodiment of the present application. A multi-LED structure  900  is formed by bonding one horizontal structure of the light-emitting diode chip  200  and one vertical structure of the light-emitting diode chip  300  back to back through a conductive bonding layer  901 . The structure of the light-emitting diode chip  200  can comprise GaN series material which emits blue light and the structure of the light-emitting diode chip  300  can comprise AlGaInP series material which emits red light. Besides, an intermediate substrate (not shown in the figure) can be formed between the structures of the light-emitting diode chips  200  and  300 . The intermediate substrate can be a transparent growth substrate of the blue light-emitting diode chip  200 . Besides, a mirror (not shown in the figure) can be further formed at one side of the intermediate substrate to enhance the light extraction efficiency of the light-emitting diode device  40 . 
         [0035]    The multi-LED structure  900  is attached to the transparent substrate  404  and electrically connected to the circuit (not shown in the figure) on the transparent substrate  404  through directly bonding, solder bonding, and/or wire bonding. The transparent substrate  404  of a light-emitting device  900  is further attached to a carrier  701  having a reflective surface  703  by an adhering material  704  wherein the carrier  701  is a printed circuit board, a ceramics substrate, or a silicon substrate. In a preferred embodiment, the transparent substrate  404  is approximately perpendicular to the carrier  701 . The circuit (not shown in the figure) of the transparent substrate  404  is electrically connected to a first electrode (ex. p electrode)  701   a  and a second electrode (ex. n electrode)  701   b  of the carrier  701  respectively. The diffusers  702  are filled in the light-emitting diode device  40  to scatter the light emitted from the light-emitting device  900 . The light (as the arrows indicating in  FIG. 9 ) passes through the transparent substrate  404  and is emitted out from the second surface  404   b . In this embodiment, because the vertical structure of the light-emitting diode chip  300  is electrically connecting to the horizontal structure of light-emitting diode chip  200  through the conductive bonding layer  901 , the structure of the light-emitting diode chip  200  and the structure of the light-emitting diode chip  300  are electrically connected to each other in series. 
         [0036]      FIG. 10  is a lateral-view of a backlight module  50  of the liquid crystal display devices accompanied with any one of the embodiments of the present application. A plurality of light-emitting diode devices  10  is attached to a carrier  801  having a reflecting layer  802  on the bottom by an adhering material  804  wherein the carrier is a printed circuit board, a ceramics substrate, or a silicon substrate. The p and n electrode of the light-emitting device is electrically connected to the p and n electrode of the carrier respectively wherein the structure of the light-emitting diode device and the manufacturing method thereof is the same with illustration of  FIG. 6  described above. The light emitted from the plurality light-emitting diode devices passes through the thin-film material  803  with different functions, such as prism sheet, to uniformly emit the desired light, and a backlight module  30  of the liquid crystal display device is formed accordingly. 
         [0037]      FIG. 11  is an illustration of another backlight module  60  coupled with a polarizer of the liquid crystal display device as shown in  FIG. 10 . A polarizer  902  having a reflecting layer  901  on the bottom is covered with a thin-film material  903  on the top layer. The polarizer coupled with a plurality of lateral light-emitting diode device  20  to form a backlight module  60  of the liquid crystal display device. The lateral light emitted from the backlight module  60  is guided to the polarizer  902  (as the arrows indicating in  FIG. 11 ) wherein the downward light is reflected from the reflecting layer  901  to the polarizer  902 . The mixed and polarized light is emitted through the thin-film material  903  to the other structure of the liquid crystal display device, such as liquid crystal layer wherein the emitting direction of the light is as the arrows indicating in  FIG. 11 .