TWI389359B - Solid-state lighting device and light source module - Google Patents

Description

Solid state light emitting element and light source module

The present invention relates to a solid state light emitting device, and a light source module including the solid state light emitting device.

Light Emitting Diode (LED) is a solid-state light-emitting element whose electrical, optical properties and lifetime are sensitive to temperature. Generally, higher temperatures result in low internal quantum effects and a much shorter lifetime; while semiconductor resistance decreases with increasing temperature, and slipping resistance will result in larger currents and more thermal energy, resulting in heat buildup. The occurrence of a phenomenon; this thermal destruction of the loop usually accelerates the destruction of the working efficiency of the light-emitting diode.

As shown in FIG. 1 , a typical light emitting diode 100 includes a package body 102 , a light emitting diode chip 104 and a resin layer 106 . The package 102 is formed by injecting a plastic 1022 onto a prefabricated metal frame 1020. The LED substrate 104 is disposed on the metal frame 1020 and electrically connected to the metal frame 1020. The resin layer 106 and the package are The bodies 102 are combined to seal the light emitting diode wafer 104. During operation, the heat generated when the LED wafer 104 emits light is dissipated via the metal frame 1020. However, since the metal frame 1020 electrically connects the LED chip 104 as an electrode and the heat dissipation of the LED wafer 104, the thermal resistance of the LED 100 is increased, thereby causing the The overall heat dissipation performance of the light-emitting diode 100 is not good, and on the other hand, it may also have a negative influence on the conductive performance of the light-emitting diode 100.

In view of the above, it is necessary to provide a solid-state light-emitting element having good heat dissipation performance, and a light source module including the solid-state light-emitting element.

A solid state light emitting device having good heat dissipation performance, and a light source module including the solid state light emitting device will be described below by way of embodiments.

A solid state light emitting device comprising a thermally conductive layer, an electrically insulating layer, two electrode pin layers, and a solid state light emitting wafer. The thermally conductive layer has a first surface. The electrically insulating layer is disposed on the first surface of the heat conducting layer, and has a second surface away from the side of the heat conducting layer, wherein the electrically insulating layer defines a through hole inwardly from the second surface to expose the heat conducting layer. The heat conducting layer has a bearing surface corresponding to the through hole. The two electrode pin layers are isolated from each other and disposed on the second surface, and each of the electrode pin layers has a third surface away from one side of the electrically insulating layer. The solid state light emitting chip is disposed on the bearing surface and electrically connected to the two electrode pin layers respectively.

And a light source module comprising at least one solid state light emitting component, a circuit board, and a heat sink. The at least one solid state light emitting device comprises a thermally conductive layer, an electrically insulating layer, two electrode pin layers, and a solid state light emitting wafer. The thermally conductive layer has a first surface. The electrically insulating layer is disposed on the first surface of the heat conducting layer, and has a second surface away from the side of the heat conducting layer, wherein the electrically insulating layer defines a through hole inwardly from the second surface to expose the heat conducting layer. The heat conducting layer has a bearing surface corresponding to the through hole. The two electrode pin layers are isolated from each other and disposed on the second surface, and each of the electrode pin layers has a third surface away from one side of the electrically insulating layer. The solid state light emitting chip is disposed on the bearing surface and electrically connected to the two electrode pin layers respectively. The circuit board is in thermal contact with the two electrode pin layers, and the circuit board defines at least one optical through hole corresponding to the solid state light emitting element, and light emitted by the solid state light emitting chip can be transmitted to the outside through the light through hole. The heat sink is located on a side of the substrate away from the circuit board and in thermal contact with the heat conductive layer.

Compared with the prior art, the solid-state light-emitting element includes a heat-conducting layer and an electrode pin layer, and the solid-state light-emitting chip is disposed on the heat-conducting layer while being powered by the electrode pin layer, and the heat-conducting layer and the electrode pin layer are The electrically insulating layer is isolated, so the solid state light emitting element is thermally and electrically separated and has good heat dissipation performance.

The embodiments of the present invention will be further described in detail below with reference to the drawings.

Referring to FIG. 2, a first embodiment of the present invention provides a solid state light emitting device 10 comprising: a solid state light emitting chip 11, a heat conducting layer 13, an electrically insulating layer 15, and two electrode pin layers 17.

The solid-state light-emitting chip 11 is specifically an LED chip 11 having a light-emitting surface 110 and a bottom surface 112 opposite to the light-emitting surface 110. The light-emitting surface 110 is provided with a positive electrode (not shown) and a negative electrode. (not shown). Specifically, the LED wafer 11 may include a phosphide such as Al _x In _y Ga _(1-xy) P (0≦x≦1, 0≦y≦1, x+y≦1) or an arsenide such as AlInGaAs, including phosphorus. The LED wafer 11 of the compound or arsenide can emit visible light in the yellow to red wavelength band. Of course, the LED chip 11 may also be made of other materials such as a nitride semiconductor (In _x Al _y Ga _(1-xy) N, 0≦x≦1, 0≦y≦1, x+y≦1). The substrate of the LED chip 11 is an intrinsic semiconductor or an unintentionally doped semiconductor. The carrier concentration of the substrate is less than or equal to 5×10 ⁶ cm ⁻³ . The lower the carrier concentration is, the lower the conductivity of the substrate is, so that the current is prevented from flowing through the substrate. Preferably, the substrate has a carrier concentration of less than or equal to 2 x 10 ⁶ cm ^-3 . The substrate can be made of materials such as spinel, SiC, Si, ZnO, GaN, GaAs, GaP, AlN, etc., of course, the substrate can also be made of materials with better thermal conductivity and lower conductivity, such as diamonds. .

The heat conducting layer 13 is for dissipating heat from the solid state light emitting wafer 11. In this embodiment, the heat conducting layer 13 is plate-shaped and has a first surface 130 and a first bottom surface 132 opposite to the first surface 130. The material of the heat conductive layer 13 may be a metal such as copper, aluminum or the like. Of course, the material of the heat conductive layer 13 may also be an alloy such as an alloy containing copper or aluminum.

In this embodiment, the heat conductive layer 13 has a solid structure. It can be understood that the heat conducting layer 13 can also be a porous structure, which can have a plurality of irregular pores, which can enhance the circulation of the gas, so that the heat conducting layer 13 obtains a better heat dissipation effect.

The electrically insulating layer 15 is disposed on the first surface 130 of the heat conducting layer 13, and may specifically be made of a material having better electrical insulating properties, such as polyester, polyimide film (PI), polycarbonate (PC), and pressure. PMMA, polymer, silicone, epoxy, spin on glass (SOG), yttrium oxide (SiO ₂ ), tantalum nitride (Si _x N _y ), At least one of cerium oxynitride (SiON), titanium oxide (TiO ₂ ), titanium nitride (TiO ₂ ), and aluminum oxide (Al _x O _y ). The electrically insulating layer 15 has a second surface 150 away from one side of the thermally conductive layer 13. A central portion of the electrically insulating layer 15 defines a through hole 15a inwardly from the second surface 150 to expose the thermally conductive layer 13. The heat conducting layer 13 has a bearing surface 133 corresponding to the through hole 15a. In this embodiment, the bearing surface 133 is coplanar with the first surface 130.

The two electrode pin layers 17 are respectively disposed on the second surface 150 of the electrically insulating layer 15, and the two electrode pin layers 17 are isolated from each other. In this embodiment, the two electrode pin layers 17 are located on opposite sides of the through hole 15a of the electrically insulating layer 15. It can be understood that the two electrode pin layers 17 can also be disposed on the same side of the through hole 15a, which is not limited to the specific embodiment. The two electrode pin layers 17 respectively have a third surface 170 away from one side of the electrically insulating layer 15 . In this embodiment, the two electrode pin layers 17 have the same thickness, and correspondingly, the two third surfaces 170 are coplanar. In addition, each of the electrode pin layers 17 may specifically be made of a metal material such as copper, gold, aluminum, indium, tin, and an alloy of the above metals. Of course, other materials such as indium tin oxide (ITO) may also be used. The thickness of the two electrode pin layers 17 is greater than 3 microns, respectively. Preferably, the thickness of the two electrode pin layers 17 is greater than 7 microns, respectively.

The solid-state light-emitting wafer 11 is disposed on the bearing surface 133 of the heat-conducting layer 13 and is located in the through-hole 15a of the electrically insulating layer 15. Specifically, the bottom surface 112 of the solid-state light-emitting chip 11 and the bearing surface 133 of the heat-conducting layer 13 are connected by a thermal conductive adhesive such as Ag epoxy, so that the solid-state light-emitting wafer 11 is in thermal contact with the heat conductive layer 13. . It can be understood that the solid-state light-emitting chip 11 and the heat-conducting layer 13 can also be connected by a solder bonding process, in particular, a solder ball is disposed between the solid-state light-emitting chip 11 and the heat-conducting layer 13 in a temperature environment. The solder balls are melted and cooled to cause the solid-state light-emitting wafer 11 to be connected to the heat-conducting layer 13. Of course, the solid-state light-emitting chip 11 and the heat-conducting layer 13 may also be connected by a eutectic process, specifically pressing the solid-state light-emitting chip 11 under high temperature and ultrasonic environment, so that the solid-state light is emitted. The wafer 11 is bonded to the heat conductive layer 13. In addition, the positive and negative electrodes of the solid state light emitting wafer 11 are wire bonded to the two electrode pin layers 17. In this embodiment, the solid state light emitting wafer 11 is respectively connected to the third surface 170 of the two electrode pin layers 17 by two metal wires 18. Preferably, the light emitting surface 110 of the solid state light emitting chip 11 is coplanar with the third surface 170 of the two electrode pin layers 17. Since the light emitting surface 110 of the solid state light emitting chip 11 is coplanar with the third surface 170 of the two electrode pin layers 17, the metal wires 18 are connected to the positive and negative electrodes of the solid state light emitting chip 11, and the electrode pin layer 17 When the third surface 170 is used, there is no need to further adjust the height of the connection of the metal wires 18, that is, the heights of the two ends of the metal wires 18 are the same, which is advantageous for saving the manufacturing process and improving the productivity.

The solid state light emitting device 10 can further include a light transmissive protective layer 19 for sealing the solid state light emitting wafer 11. Specifically, the material of the light transmissive protective layer 19 may be resin, silicone, epoxy resin, polymethyl methacrylate (PMMA), or glass. In this embodiment, the light transmissive protective layer 19 is substantially semi-spherical. The light-transmissive protective layer 19 may be filled with a light-converting substance such as phosphor powder or the like to convert the light emitted from the solid-state light-emitting chip 11 into other color lights, and after being mixed and emitted. The phosphor powder may include red, yellow, and green phosphor powder, and the material may be Sulfides, Aluminates, Oxides, Silicones, or Nitredes. Wait. Specifically, the phosphor powder may be Ca ₂ Al ₁₂ O ₁₉ :Mn, (Ca, Sr, Ba)Al ₂ O ₄ :Eu, Y ₃ A _l5 O12Ce ³⁺ (YAG), Tb ₃ Al ₅ O ₁₂ : Ce ³⁺ (YAG), BaMgAl ₁₀ O ₁₇ :Eu ²⁺ (Mn ²⁺ ), Ca ₂ Si ₅ N ₈ :Eu ²⁺ , (Ca, Sr, Ba)S:Eu ²⁺ , (Mg, Ca, Sr,Ba) ₂ SiO ₄ : Eu ²⁺ , (Mg, Ca, Sr, Ba) ₃ Si ₂ O ₇ : Eu ²⁺ , Ca ₈ Mg(SiO ₄ ) ₄ Cl ₂ :Eu ²⁺ , Y ₂ O ₂ S: Eu ³⁺ , (Sr, Ca, Ba)Si _x O _y N _z :Eu ²⁺ , (Ca,Mg, Y)SiwAl _x O _y N _z :Eu ²⁺ , CdS, CdTe or CdSe, and the like.

In operation, an external power source (not shown) supplies power to the solid state light emitting wafer 11 via the electrode pin layer 17 and the metal wires 18. On the one hand, the light emitted from the solid-state light-emitting wafer 11 is transmitted through the light-transmitting protective layer 19; on the other hand, the heat generated by the solid-state light-emitting wafer 11 is led out through the heat conductive layer 13.

Since the two electrode pin layers 17 and the heat conductive layer 13 are separated from each other by the two sides of the electrically insulating layer 15 so as to be separated from each other, the paths of the conductive and heat conduction of the solid state light emitting chip 11 can be isolated from each other, so that the solid state light emitting wafer 11 is ensured. The heat generated by the solid-state light-emitting chip 11 can be preferably led out through the heat-conducting layer 13 at the same time, and the solid-state light-emitting element 10 has better light-emitting characteristics and better heat dissipation efficiency.

Referring to FIG. 3, a second embodiment of the present invention provides a solid state light emitting device 20 substantially the same as the solid state light emitting device 10 provided in the first embodiment, except that the first surface 230 of the heat conducting layer 23 further extends. a bearing block 233 of the heat conducting layer 23 is located on a side of the bump 23a away from the first surface 230, and the bearing surface 233 and the electrically insulating layer 25 are disposed. The second surface 250 is coplanar. Since the bearing surface 233 is coplanar with the second surface 250 of the electrically insulating layer 25, the electrically insulating layer 25 can be formed on the heat conducting layer 23 by using a printing technique without complicated processing. Exposure development technology is used for production.

Referring to FIG. 4, a third embodiment of the present invention provides a solid state light emitting device 30, which is substantially the same as the solid state light emitting device 20 provided in the second embodiment, except that the bearing surface 333 of the bump 33a and the electrode pin layer The third surface 370 of the 37 is coplanar; the solid state light emitting element 30 further includes a reflecting cup 38 partially covering the electrode pin layer 37 and located in the electrically insulating layer 35 away from the heat conducting layer 33 Side, and the reflective bowl 38 is disposed around the solid-state light-emitting chip 31; further, the reflective bowl 38 has a reflective surface 380 therein, the transparent protective layer 39 fully filling the reflective surface 380 and sealing the solid-state light-emitting chip 31; The layer 39 is away from the solid-state light-emitting chip 31 and has a light-emitting surface 390. The light emitted by the solid-state light-emitting chip 31 is transmitted and converted by the light-transmitting protective layer 39, and then emitted from the light-emitting surface 390 to the outside.

In this embodiment, the light exit surface 390 is a plane. It can be understood that the light exit surface 390 can be other shapes. In the solid state light emitting device 40 provided by the fourth embodiment of the present invention, the light exit surface 490 of the light transmissive protective layer 49 is a convex curved surface (refer to FIG. 5).

The present invention also provides a light source module, which can select any of the solid state light emitting elements 10-40 of any of the first to fourth embodiments. Hereinafter, the light source module will be described by taking only the case of using the solid-state light-emitting elements 30 shown in FIG. 4 as an example.

The light source module 50 shown in FIG. 6 includes three solid state light emitting elements 30, a circuit board 52, and a heat sink 54.

The heat sink 54 includes a base 540 and a plurality of heat dissipation fins 542 extending from the base 540 away from one side of the heat conductive layer 33. The pedestal 540 can be connected to the heat conducting layer 33 of the solid state light emitting device 30 by thermal reflow of solder balls. In this embodiment, the base 740 has a second bottom surface 5400. The solder ball is disposed between the second bottom surface 5400 and the first bottom surface 332 of the heat conductive layer 33. In addition, a plurality of protrusions 546 may be further extended on the second bottom surface 5400 of the base 740, and the plurality of protrusions 546 partially fill the plurality of gaps 300 respectively, so that the plurality of solid state light emitting elements 30 are buckled thereon. The heat sink 54 is placed to form a tight bond.

The circuit board 52 has a fourth surface 520 and a fifth surface 522 opposite the fourth surface 520. The fourth surface 520 of the circuit board 52 defines a light through hole 524 corresponding to each of the solid state light emitting elements 30. During installation, the fifth surface 522 of the circuit board 52 can be connected to the third surface 370 of the electrode pin layer 37 by thermal reflow, and the reflective bowl 38 and the transparent protective layer 39 penetrate the light of the circuit board 52. The via 524 protrudes from the fourth surface 520 of the circuit board 52.

The circuit board 52 is a flexible printed circuit board (FPPCB), and the substrate can be a polyester (PET), a polyimide film (PI), a polyethylene naphthenic (PEN), a thin ring. Oxygen resin, or fiberglass material (FR4), etc.

In operation, the circuit board 52 is powered by an external power source (not shown) that energizes the solid state light emitting wafer 31 after passing through the two electrode pin layers 37. On the one hand, the light emitted by the solid-state light-emitting chip 31 is transmitted through the light-transmitting protective layer 39 and transmitted through the light-transmitting protective layer 39. On the other hand, the heat generated by the solid-state light-emitting chip 39 can be conducted to the heat sink 54 through the heat-conducting layer 33 for heat dissipation.

Since the two electrode pin layers 37 and the heat conductive layer 33 are separated from each other, the paths of the conductive and heat conduction of the solid state light emitting chip 31 can be isolated from each other, so that the solid state light emitting chip 31 is supplied with power to make it emit light before the solid state is lifted. The heat generated by the illuminating chip 31 is preferably transmitted to the heat sink 54 via the heat conducting layer 33 for heat dissipation. The light source module 50 has better illuminating characteristics and better heat dissipation efficiency.

In summary, the present invention has indeed met the requirements of the invention patent, and has filed a patent application according to law. However, the above description is only a preferred embodiment of the present invention, and it is not possible to limit the scope of the patent application of the present invention. Equivalent modifications or variations made by persons skilled in the art in light of the spirit of the invention are intended to be included within the scope of the following claims.

100‧‧‧Lighting diode

102‧‧‧Package

104‧‧‧Light Emitter Wafer

106‧‧‧ resin layer

1020‧‧‧Metal frame

1022‧‧‧ plastic

10, 20, 30, 40‧‧‧ solid state light-emitting elements

11, 31‧‧‧ Solid-state light-emitting chips

13, 23, 33‧‧‧ Thermal Conductive Layer

15, 25, 35‧‧‧ electrical insulation

17, 37‧‧‧electrode pin layers

18‧‧‧Metal wire

19, 39, 49‧‧ ‧ light protective layer

110‧‧‧Glossy surface

112‧‧‧ bottom

130, 230‧‧‧ first surface

132, 332‧‧‧ first bottom

133, 233, 333‧‧ ‧ bearing surface

150, 250‧‧‧ second surface

15a, 25a‧‧‧through hole

170, 370‧‧‧ third surface

23a, 33a, 546‧‧ ‧ bumps

38‧‧‧Reflection bowl

380‧‧‧reflecting surface

390, 490‧‧‧ light exit surface

300‧‧‧ gap

50‧‧‧Light source module

52‧‧‧ boards

520‧‧‧ fourth surface

522‧‧‧ fifth surface

524‧‧‧Light through hole

54‧‧‧heating device

540‧‧‧Base

542‧‧‧Fixed fins

5400‧‧‧second bottom surface

1 is a schematic cross-sectional view of a solid state light emitting device in the prior art.

Fig. 2 is a schematic cross-sectional view showing a solid state light emitting device according to a first embodiment of the present invention.

Figure 3 is a schematic cross-sectional view showing a solid state light emitting device according to a second embodiment of the present invention.

Figure 4 is a schematic cross-sectional view showing a solid state light emitting device according to a third embodiment of the present invention.

Figure 5 is a schematic cross-sectional view showing a solid state light emitting device according to a fourth embodiment of the present invention.

Fig. 6 is a schematic cross-sectional view showing a light source module using the solid state light emitting element shown in Fig. 4.

10‧‧‧Solid light-emitting elements

11‧‧‧Solid luminescent wafer

13‧‧‧Conducting layer

15‧‧‧Electrical insulation

17‧‧‧Electrode pins

18‧‧‧Metal wire

19‧‧‧Light protective layer

110‧‧‧Glossy surface

112‧‧‧ bottom

130‧‧‧ first surface

132‧‧‧ first bottom surface

133‧‧‧ bearing surface

150‧‧‧second surface

15a‧‧‧through hole

170‧‧‧ third surface

Claims (11)

A solid state light emitting device comprising:
a thermally conductive layer having a first surface;
An electrically insulating layer disposed on the first surface of the thermally conductive layer, the electrically insulating layer having a second surface away from the side of the thermally conductive layer, the electrically insulating layer opening a through hole inwardly from the second surface to expose The heat conducting layer has a bearing surface corresponding to the through hole;
Two electrode pin layers are separated from each other and respectively disposed on the second surface, each electrode pin layer having a third surface away from one side of the electrically insulating layer;
A solid state light emitting chip is disposed on the carrying surface and electrically connected to the two electrode pin layers respectively. The solid state light emitting device of claim 1, wherein the bearing surface is coplanar with the first surface. The solid-state light-emitting device of claim 2, wherein the solid-state light-emitting chip has a light-emitting surface away from one side of the bearing surface, and the light-emitting surface is coplanar with each of the third surfaces. The solid-state light-emitting device of claim 1, wherein the first surface of the heat-conducting layer further extends a bump received in the through-hole of the electrically insulating layer, and the bearing surface of the heat-conducting layer is located at the convex The block is away from one side of the first surface, and the bearing surface is coplanar with the second surface. The solid-state light-emitting device of claim 1, wherein the first surface of the heat-conducting layer further extends a bump received in the through-hole of the electrically insulating layer, and the bearing surface of the heat-conducting layer is located at the convex The block is away from one side of the first surface, and the bearing surface is coplanar with the electrode pin layer. The solid state light emitting device of claim 1, wherein the solid state light emitting wafer comprises a light emitting diode chip. The solid-state light-emitting device of claim 1, wherein the heat-conducting layer further extends from the side of the electrically insulating layer to a plurality of spaced-apart heat sinks. A light source module comprising:
At least one solid state light emitting element, the at least one solid state light emitting element comprising:
a thermally conductive layer having a first surface,
An electrically insulating layer disposed on the first surface of the thermally conductive layer, the electrically insulating layer having a second surface away from the side of the thermally conductive layer, the electrically insulating layer opening a through hole inwardly from the second surface to expose The heat conducting layer has a bearing surface corresponding to the through hole,
Two electrode pin layers are separated from each other and respectively disposed on the second surface, and each of the electrode pin layers has a third surface away from a side of the electrically insulating layer.
a solid-state light-emitting chip disposed on the bearing surface and electrically connected to the two electrode pin layers respectively;
a circuit board respectively in thermal contact with the two electrode pin layers, and the circuit board defines at least one optical through hole corresponding to the solid state light emitting element, and the light emitted by the solid state light emitting chip is transmitted through the light through hole to And a heat sink disposed on a side of the substrate away from the circuit board and in thermal contact with the thermally conductive layer. The light source module of claim 8, wherein the heat conducting layer is a plate-like structure, the heat dissipating device comprises a base in thermal contact with the heat conducting layer, and the base is away from the heat conducting layer A plurality of fins extending from one side. The light source module of claim 8, wherein the at least one solid state light emitting element comprises a plurality of spaced apart solid state light emitting elements, and a gap between adjacent two solid state light emitting elements. The light source module of claim 10, wherein the heat dissipating device further extends a plurality of protrusions corresponding to the gap, the plurality of protrusions partially filling the plurality of gaps, respectively.