Thermoelectric separation LED module and manufacturing method thereof

Abstract

The invention discloses a thermoelectrically separated LED device module and a manufacturing method thereof, the thermoelectrically separated LED device module comprises a radiator, an insulating layer, a PCB and an LED device, the top surface of the radiator is provided with a groove for embedding the lower part of the PCB, and the bottom surface of the radiator is provided with a plurality of radiating fins; one end of the groove is concave and is provided with a first groove section and a second groove section which are parallel to each other, and the PCB is provided with a connecting part between the first groove section and the second groove section; the LED device comprises a substrate installed on the radiator, an external bonding pad, a light-emitting layer and a light conversion layer are arranged on the substrate from bottom to top, a light blocking layer surrounds the light-emitting layer and the side face of the light conversion layer, and the end, away from the light-emitting layer, of the external bonding pad abuts against the lower surface of the connecting part. The connecting part is provided with two conductive through holes, and the external bonding pad can seal the bottoms of the two conductive through holes; the insulating layer surrounds the side surface of the substrate. The manufacturing method of the thermoelectric separation LED device module is used for manufacturing the LED device module, the manufacturing method is simple, thermoelectric separation of the LED device and the PCB can be achieved, and the heat dissipation effect is good.

Description

Technical Field

[0001] The invention belongs to the technical field of LEDs, and in particular relates to a thermal and electrical separation LED module and a manufacturing method thereof. Background Art

[0002] At present, there are two ways to connect high-power LED modules: wire bonding, which connects the LED wire bonding pad to the PCB pad. This method requires high-precision bonding equipment and high-reliability wire arcs, which greatly limits the mass production and use of LED modules. Another method is soldering, which connects the bottom pad of the LED to the PCB pad with solder paste to achieve conduction. However, heat and electricity are both conducted through the solder paste layer. In this module where heat and electricity are not separated, the solder paste layer is very likely to crack or even break during long-term use.

[0003] Among them, high-power ceramic LEDs generate a lot of heat, and their heat dissipation restricts the lumen maintenance rate of LEDs in hot states. High-power ceramic LEDs use separate heat dissipation and are only electrically connected to PCBs through external connections. For such thermal and electrical separation modules, the electrical connection between the PCB and the LED is usually made by wire bonding. However, the wire bonding of high-power LEDs requires high reliability of bonding equipment and wire arcs, which is not easy to manufacture. In addition, existing high-power LED modules usually use PCBs as heat dissipation and circuit conduction carriers, and LED lamp beads as heat sources are welded on the PCBs; and PCBs are generally made of FR-4 and other boards with poor heat dissipation performance. It is difficult for the heat generated by the LED to be conducted away through the PCB by heat transfer, and the heat dissipation effect is poor, so that heat is concentrated at the LED, causing the LED to heat up and light decay or even die.

[0004] Therefore, a new technology is needed to solve the problems in the prior art that LED modules are inconvenient to manufacture and have poor heat dissipation effects. Summary of the invention

[0005] In order to solve the above problems in the prior art, the present invention provides a thermoelectrically separated LED module and a manufacturing method thereof, which can realize the separate connection between the PCB board and the LED heat source, avoid the lead bonding between the PCB circuit board and the LED pad, thereby avoiding the risk of bonding failure such as wire collapse or wire breakage, shortening the heat conduction path of the LED heat source, greatly reducing the heat accumulation of the LED, and has a simple structure and is easy to manufacture.

[0006] The present invention adopts the following technical solutions:

[0007] A thermal and electrical separation LED module comprises a heat sink, a PCB board and an LED device, wherein the top surface of the heat sink is provided with a groove for the lower part of the PCB board to be embedded, and the bottom surface is provided with a plurality of heat dissipation fins at intervals;

[0008] One end of the PCB board is horizontally provided with a connecting portion. The horizontal cross-section of the groove is concave at this end. The groove is provided with a first groove section and a second groove section that are parallel to each other and protrude at this end. The connecting portion is located between the first groove section and the second groove section and above the radiator.

[0009] The LED device is mounted on the top surface of the radiator and one end is located below the connecting portion. The LED device includes a substrate and a light-emitting layer, a light-converting layer, and a light-blocking layer provided on the top of the substrate. The light-emitting layer is provided at one end of the substrate away from the PCB board. The light-converting layer covers the light-emitting layer. The light-blocking layer is annularly arranged around the sides of the light-emitting layer and the light-converting layer.

[0010] An external pad is also provided on the upper surface of the substrate. One end of the external pad away from the light-emitting layer abuts against the lower surface of the connecting portion. Two conductive through holes are vertically provided on the connecting portion. The upper surface of the external pad can close the bottom openings of the two conductive through holes.

[0011] An insulating layer is further included. The insulating layer surrounds the side surface of the substrate.

[0012] As a further improvement of the technical solution of the present invention, there is a gap between the side of the light-blocking layer close to the boss and the side surface of the boss.

[0013] As a further improvement of the technical solution of the present invention, bottom pads are provided on the bottom surface of the substrate.

[0014] As a further improvement of the technical solution of the present invention, an adhesive layer is further included. The adhesive layer is located between the bottom pad and the radiator. The adhesive layer is used to fix the substrate to the radiator.

[0015] As a further improvement of the technical solution of the present invention, the radiator has a first end and a second end that are oppositely arranged. The LED is located between the groove and the edge of the second end. There is a spacing between the side of the insulating layer away from the PCB board and the edge of the second end.

[0016] As a further improvement of the technical solution of the present invention, a first convex portion and a second convex portion corresponding to the first groove section and the second groove section are provided on the PCB board. The upper surfaces of the first convex portion, the connecting portion, and the second convex portion are flush with the top surface of the PCB board. The lower surfaces of the first convex portion and the second convex portion are both flush with the bottom surface of the PCB board. The lower part of the first convex portion is embedded in the first groove section. The lower part of the second convex portion is embedded in the second groove section. The first convex portion, the connecting portion, and the second convex portion are sequentially connected to form a U-shaped structure with an opening downward.

[0017] As a further improvement of the technical solution of the present invention, the bottom of the groove is provided with a first boss and a second boss at intervals, and the PCB board is provided with a first limiting hole and a second limiting hole corresponding to the first boss and the second boss respectively.

[0018] As a further improvement of the technical solution of the present invention, the radiator is further provided with a first mounting hole, the first mounting hole is located between the first boss and the second boss, and the PCB board is provided with a second mounting hole with the same diameter and coaxial with the first mounting hole; the first boss is located on a side of the first mounting hole close to the first end, and the second boss is located on a side of the first mounting hole close to the second end;

[0019] A plurality of heat dissipation fins are respectively distributed on both sides of the first mounting hole.

[0020] As a further improvement of the technical solution of the present invention, the heat sink is further provided with a first positioning hole and a second positioning hole, the first positioning hole and the second positioning hole are both close to the second end and are respectively located on both sides of the LED device, and the center line of the light-emitting layer coincides with the center line of the first positioning hole and the second positioning hole.

[0021] A method for manufacturing a thermoelectrically separated LED module, for manufacturing the thermoelectrically separated LED module as described above, comprises the following steps:

[0022] S1. First, the LED device is bonded by SMT bonding, and then the LED device is fixed on the top surface of the heat sink by thermal conductive glue;

[0023] S2. Using insulating glue to form the insulating layer around the LED device;

[0024] S3. Place the PCB board in the groove of the heat sink, and then press the PCB board downward to make the bottom surface of the PCB board close to the bottom of the groove, and at the same time, the lower surface of the connecting portion is close to the upper surface of the external solder pad of the LED device;

[0025] S4. Fill each of the conductive through holes of the PCB board with solder paste by dispensing or spraying, and then connect the LED device to the PCB board by reflow soldering, so that the LED device is electrically connected to the PCB board.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] In the thermoelectrically separated LED module of this scheme, the PCB board is electrically connected to the LED through the conductive through-hole on the connecting part, so that the PCB board can be individually connected to the heat source of the LED device, avoiding the wire bonding between the PCB circuit board and the LED pad, thereby avoiding the risk of bonding failure such as wire collapse or wire breakage. The LED device is directly connected to the heat sink, shortening the heat conduction path of the LED heat source, greatly reducing the heat accumulation of the LED, and has a simple structure and a simple manufacturing method, which is easy to manufacture. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The technology of the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments:

[0029] Figure 1 is a top view of the LED device module with thermal and electrical separation of the present invention;

[0030] Figure 2 yes Figure 1 Schematic diagram of the cross section of the middle AA section;

[0031] Figure 3 yes Figure 2 A partial enlarged view of the structure of part C in the middle;

[0032] Figure 4 yes Figure 1 Schematic diagram of the cross section of the middle BB section;

[0033] Figure 5 is a top view of the PCB board structure of the present invention;

[0034] Figure 6 It is a top view of the radiator structure;

[0035] Figure 7 yes Figure 6 Schematic diagram of the cross section of the middle AA section;

[0036] Figure 8 It is a top view of the LED device mounted on the heat sink;

[0037] Fig. 9 yes Figure 8 Schematic diagram of the cross section of the middle AA section;

[0038] Fig.10 This is a top view after the insulating dam is built around the LED device;

[0039] Fig.11 yes Fig.10 Schematic diagram of the cross section of the AA section.

[0040] Reference numerals:

[0041] 1- radiator; 11- cooling fin; 12- groove; 121- first groove section; 122- second groove section; 13- first boss; 14- second boss; 15- first mounting hole; 16- first end; 17- second end; 18- first positioning hole; 19- second positioning hole; 20- placement area;

[0042] 2-PCB board; 21-connecting part; 211-conductive through hole; 2111-copper layer; 22-first limiting hole; 23-second limiting hole; 24-second mounting hole; 25-FR-4 plate; 26-circuit layer; 27-solder resist layer; 28-first convex part; 29-second convex part;

[0043] 3-LED device; 31-light conversion layer; 32-light emitting layer; 33-light blocking layer; 34-substrate; 35-external solder pad; 36-bottom solder pad;

[0044] 4- Adhesion layer;

[0045] 5-Insulation layer. DETAILED DESCRIPTION

[0046] The following will be combined with the embodiments and drawings to clearly and completely describe the concept, specific structure and technical effects of the present invention, so as to fully understand the purpose, scheme and effect of the present invention. It should be noted that the embodiments in this application and the features in the embodiments can be combined with each other without conflict. The same reference numerals used throughout the drawings indicate the same or similar parts.

[0047] It should be noted that, unless otherwise specified, when a feature is referred to as being "fixed" or "connected" to another feature, it may be directly fixed or connected to the other feature, or it may be indirectly fixed or connected to the other feature. In addition, the descriptions of up, down, left, right, etc. used in the present invention are only relative to the relative positional relationship of the components of the present invention in the drawings.

[0048] Reference Figures 1 to 11 A heat-electric separation LED module comprises a heat sink 1, a PCB board 2 and an LED device 3. The top surface of the heat sink 1 is provided with a groove 12 for the lower part of the PCB board 2 to be embedded, and the bottom surface is provided with a plurality of heat dissipation fins 11 at intervals. A connecting portion 21 is horizontally provided on the side surface of one end of the PCB board 2. The horizontal cross-section of the groove 12 is concave at this end. The groove 12 is provided with a first groove section 121 and a second groove section 122 parallel to each other at this end. The connecting portion 21 is located between the first groove section 121 and the second groove section 122 and is located above the heat sink 1. The top surface of the connecting portion 21 is flush with the top surface of the PCB board 2, and the bottom surface is higher than the bottom surface of the PCB board 2.

[0049] The LED device 3 is mounted on the top surface of the heat sink 1 and one end of the LED device 3 is located below the connecting portion 21. The LED device 3 includes a substrate 34 and a light-emitting layer 32, a light conversion layer 31, and a light blocking layer 33 arranged on the top of the substrate 34. The light-emitting layer 32 is arranged at one end of the substrate 34 away from the PCB board 2. The light conversion layer 31 covers the top of the light-emitting layer 32. The light blocking layer 33 is annularly surrounded by the sides of the light-emitting layer 32 and the light conversion layer 31. The side of the light-emitting layer 32 and the lower part of the side of the light conversion layer 31 are all wrapped by the light blocking layer 33. Only the top or top surface of the light conversion layer 31 emits light. The upper end surface of the light conversion layer 31 is higher than the top surface of the PCB board 2. The upper end surface of the light conversion layer 31 is located at the highest point of the overall structure to prevent the light from being blocked by other parts. The light-emitting layer 32 is disposed on the substrate 34 , and the substrate 34 of the LED is directly fixed on the heat sink 1 , forming a heat dissipation path that directly dissipates heat to the heat sink 1 , shortening the heat conduction path of the LED heat source and greatly reducing the heat accumulation of the LED.

[0050] The upper surface of the substrate 34 is also provided with an external solder pad 35, and one end of the external solder pad 35 away from the light-emitting layer 32 is located below the connecting portion 21 and abuts against the lower surface of the connecting portion 21. Two conductive through holes 211 are vertically provided on the connecting portion 21, and the two conductive through holes 211 are spaced and symmetrically arranged on the connecting portion 21. The upper surface of the external solder pad 35 can close the bottom openings of the two conductive through holes 211, wherein each of the conductive through holes 211 is filled with solder paste. The LED module of the thermal and electrical separation of this scheme also includes an insulating layer 5, referring to Fig.10 The insulating layer 5 surrounds the side of the substrate 34, and there is a gap between the substrate 34 and the side of the PCB board 2. Part of the insulating layer 5 is located between the substrate 34 and the PCB board 2 to prevent the substrate 34 and the top surface of the heat sink 1 from being connected and leaking. The connecting portion 21 is convexly arranged above the heat sink 1. After the connecting portion 21 is pressed onto the external solder pad 35 of the LED, the PCB board 2 and the LED are soldered and fastened by solder paste, and are electrically connected through the conductive through hole 211, thereby avoiding wire bonding, and the LED is directly fixed on the upper surface of the heat sink 1, realizing the thermal and electrical separation of the LED heat source.

[0051] The thermoelectrically separated LED module of this solution makes the PCB board 2 with the connecting part 21 into a flip-chip structure, that is, the connecting part 21 is inverted above the external pad 35 of the LED device 3, and the electrical connection between the PCB board 2 and the LED device 3 is realized through the conductive through-hole 211 on the connecting part 21 to achieve a separate connection with the LED heat source. It avoids the wire bonding between the PCB circuit board and the LED pad, and avoids the bonding failure risks such as wire collapse or breakage. It simplifies the electrical connection method between the PCB board 2 and the LED, and realizes welding through the conventional chip mounting method, which is beneficial to mass production and facilitates the production of LED modules. The substrate 34 of the LED is directly fixed on the heat sink 1, shortening the heat conduction path of the LED heat source and greatly reducing the heat accumulation of the LED.

[0052] Specifically, there is a gap between the side of the light-blocking layer 33 close to the connecting part 21 and the side of the connecting part 21, and the side of the connecting part 21 does not contact the light-blocking layer 33.

[0053] Specifically, the bottom surface of the substrate 34 is provided with a bottom pad 36. Referring to Figure 3 , the thermoelectrically separated LED module of this solution further includes an adhesive layer 4. The adhesive layer 4 is located between the bottom pad 36 and the heat sink 1, and the adhesive layer 4 is used to fix the substrate 34 and the heat sink 1. The material of the adhesive layer 4 is thermal conductive glue. The LED and the heat sink 1 are connected through thermal conductive glue, and the thermal conductive glue has a high thermal conductivity, and its thermal conductivity includes but is not limited to 6.5W / mk, etc.

[0054] Specifically, the heat sink 1 has a first end 16 and a second end 17 arranged oppositely. The LED is located between the groove 12 and the edge of the second end 17, and there is a spacing between the side of the insulating layer 5 away from the PCB board 2 and the edge of the second end 17.

[0055] Specifically, the PCB board 2 is provided with a first convex part 28 and a second convex part 29 corresponding to the first groove section 121 and the second groove section 122 in sequence. Referring to Figure 4 , the upper surfaces of the first convex part 28, the connecting part 21, and the second convex part 29 are flush with the top surface of the PCB board 2, the lower surfaces of the first convex part 28 and the second convex part 29 are both flush with the bottom surface of the PCB board 2, the lower part of the first convex part 28 is embedded in the first groove section 121, and the lower part of the second convex part 29 is embedded in the second groove section 122. Among them, the cross-section of the sequential connection structure of the first convex part, the connecting part, and the second convex part in the vertical direction is a U-shaped structure with an opening downward.

[0056] Specifically, the bottom of the groove 12 is provided with a first boss 13 and a second boss 14 at intervals, and the PCB board 2 is provided with a first limiting hole 22 and a second limiting hole 23 corresponding to the first boss 13 and the second boss 14 in sequence, and the first limiting hole 22 and the second limiting hole 23 respectively form an interference fit with the first boss 13 and the second boss 14 of the radiator 1. The PCB board 2 is docked with the first boss 13 and the second boss 14 on the radiator 1 through the first limiting hole 22 and the second limiting hole 23, so that the PCB board 2 and the radiator 1 are positioned, and the PCB board 2 can be accurately fixed to the groove 12 of the radiator 1.

[0057] Specifically, the heat sink 1 is further provided with a first mounting hole 15, the first mounting hole 15 is located between the first convex column 13 and the second convex column 14, and the PCB board 2 is provided with a second mounting hole 24 having the same diameter and being coaxial with the first mounting hole 15; the first convex column 13 is located on a side of the first mounting hole 15 close to the first end 16, and the second convex column 14 is located on a side of the first mounting hole 15 close to the second end 17. A plurality of the heat dissipation fins 11 are respectively distributed on both sides of the first mounting hole 15. The provision of the first mounting hole 15 and the second mounting hole 24 facilitates installation and fixation with other structures.

[0058] Specifically, the heat sink 1 has a rectangular shape, and a horizontal cross section of the heat sink 1 is rectangular. The first mounting hole 15 is located at the center of the heat sink 1. The heat dissipation fins 11 are distributed on both sides of the first mounting hole 15, and there is no heat dissipation fin 11 below the first mounting hole 15. The first convex column 13 and the second convex column 14 are distributed on both sides of the first mounting hole 15, wherein the first convex column 13 is located on the left side near the first end 16, and the second convex column 14 is located on the right side near the second end 17. The heights of the first convex column 13 and the second convex column 14 are not higher than the top surface of the light-emitting layer 32 of the LED device 3.

[0059] Specifically, the upper surface of the heat sink 1 is provided with an LED placement area 20 for placing the LED, the left side of the placement area 20 is located between the first groove section 121 and the second groove section 122, and the right side is close to the second end 17. The placement area 20 is rectangular, and the area of ​​the placement area 20 is larger than the area of ​​the LED. The PCB board 2 and the groove 12 on the heat sink 1 are clearance-matched, and the depth of the groove 12 on the heat sink 1 for installing the PCB board 2 is greater than or equal to half the thickness of the PCB board 2. The shape of the groove 12 is consistent with the PCB shape, and the horizontal dimension is wider than the PCB shape, so that the PCB board 2 can be smoothly mounted in the groove 12.

[0060] Specifically, the heat sink 1 is further provided with a first positioning hole 18 and a second positioning hole 19, the first positioning hole 18 and the second positioning hole 19 are both close to the second end 17 and are respectively located on both sides of the LED device 3, the center line of the light-emitting layer 32 coincides with the center lines of the first positioning hole 18 and the second positioning hole 19, and is parallel to the edge of the heat sink 1 at the second end 17. The first positioning hole 18 and the second positioning hole 19 can both be circular holes, or the first positioning hole 18 is a circular hole and the second positioning hole 19 is an elliptical hole, the center lines of the first positioning hole 18 and the second positioning hole 19 coincide and are symmetrically distributed on both sides of the LED placement area 20, and the distances between the first positioning hole 18, the second positioning hole 19 and the edge of the heat sink 1 at the second end 17 are equal. When mounting the LED device 3, the center line of the light-emitting layer 32 coincides with the center lines of the first positioning hole 18 and the second positioning hole 19, so that the LED can be positioned in the placement area 20 of the heat sink 1.

[0061] Specifically, the PCB board 2 includes a FR-4 flat plate 25, a circuit layer 26, and a solder resist layer 27 arranged in sequence from bottom to top, and the circuit of the PCB board 2 is located on the front. The solder resist layer 27 covers the circuit layer 26, and the circuit layer 26 and the FR-4 flat plate 25 are laminated. The circuit layer 26 is 1 oz thick, and the solder resist layer 27 is made of white oil.

[0062] Specifically, the light-emitting layer 32 may be a fluorescent sheet or a fluorescent film, and only the top surface emits light. The composition of the light-blocking layer 33 includes, but is not limited to, a fluid and highly reflective material such as a mixture of TiO2 powder and silica gel. The coating composition of the external pad 35 and the bottom pad is consistent and can be well soldered with solder paste, and its composition includes, but is not limited to, nickel-palladium-gold or nickel-gold alloy.

[0063] Specifically, the solder paste between the PCB board 2 and the LED is consistent with the front circuit of the PCB, and both use medium-temperature solder paste. The mounting is achieved by tinning the patch, and then soldering is performed by a reflow soldering method. The solder paste composition includes but is not limited to Sn3.0Ag0.5Cu or Sn0.7Cu.

[0064] Reference Figures 1 to 11 A method for manufacturing a thermoelectrically separated LED module, which can be used to manufacture the thermoelectrically separated LED module as described above, comprises the following steps:

[0065] S1. First, the LED device 3 is bonded by SMT bonding, and then the LED device 3 is fixed to the top surface of the heat sink 1 by thermal conductive glue to form an LED heat dissipation path. Among them, the bottom pad is fixed to the LED placement area 20 on the heat sink 1 by glue bonding, and the glue can be a thermal conductive glue with a good thermal conductivity. The material of the heat sink 1 is aluminum alloy, the groove 12 and the first protrusion 13 and the second protrusion 14 can be formed by stamping and casting, and each heat dissipation fin 11 is riveted or welded to the bottom of the heat sink 1, and the first mounting hole 15, the first positioning hole 18, and the second positioning hole 19 can be made of precision drilling technology.

[0066] S2. Use insulating glue to build a dam around the LED device 3 to form the insulating layer 5, so as to achieve insulation between the LED and the PCB board 2, and also prevent the solder paste from flowing to the heat sink 1 and causing leakage. After using the insulating glue to build a dam, the insulating layer 5 is formed around the external solder pad 35, and part of the insulating layer 5 is located in the gap between the substrate 34 and the PCB board 2.

[0067] S3. Place the PCB board 2 in the groove 12 of the heat sink 1 by sucking it with a nozzle or mechanically grabbing it, and then press the PCB board 2 downward by a pressure head or riveting it so that the bottom surface of the PCB board 2 is closely attached to the bottom of the groove 12, and the PCB board 2 is fastened to the first boss 13 and the second boss 14 of the heat sink 1. At the same time, the lower surface of the connecting part 21 is closely attached to the upper surface of the external solder pad 35 of the LED device 3. The connecting part 21 is in the shape of a right-angle step, and the side surface of the connecting part 21 close to the second end is perpendicular to the lower surface of the connecting part 21. The connecting part 21 can be formed by a gong groove process, and the vertical depth of the connecting part 21 is equal to the sum of the thickness of the LED substrate 34 and the depth of the groove 12, that is, the vertical distance between the lower surface of the connecting part 21 and the lower surface of the PCB is equal to the vertical spacing between the upper surface of the LED substrate 34 and the bottom of the groove 12. The horizontal surface length of the connecting portion 21 is greater than the length of the LED external solder pad 35, that is, in the direction perpendicular to the first end 16 and the second end 17, the length of the lower surface of the connecting portion 21 is greater than the length of the external solder pad 35, and at the same time, the right side boundary of the connecting portion 21 does not contact the LED light blocking layer 33, and the distance between the right side surface of the connecting portion 21 and the left side surface of the LED light blocking layer 33 is at least 0.5 mm.

[0068] The bottom surface of each conductive through hole 211 directly fits the LED external solder pad 35, and the diameter of each conductive through hole 211 is smaller than the length of the LED external solder pad 35. The two conductive through holes 211 are arranged in a straight line, and the straight line structure is parallel to the edge of the heat sink 1 at the second end 17. The leftmost side of the hole wall of each conductive through hole 211 can be connected to the left boundary of the external solder pad 35, or the leftmost side of the hole wall of each conductive through hole 211 is inside the left boundary of the external solder pad 35. The distance between the rightmost side of the hole wall of the conductive through hole 211 and the right side surface of the PCB board 2 is greater than 2.5 mm. A copper layer 2111 is electroplated in the conductive through hole 211, and the thickness of the copper layer 2111 is not less than 50 um.

[0069] Among them, the external solder pad 35 is pressed by the lower surface of the connecting part 21 on the PCB, and the conductive through holes 211 are aligned at the external solder pad 35. The electrical connection between the two is achieved by tinning the conductive through hole 211 and then using a reflow soldering process. In order to prevent the solder paste from flowing to the surface of the heat sink 1, before the PCB board 2 is installed on the heat sink 1, a dam is formed around the LED external solder pad 35 using an insulating glue with good thixotropy to block it.

[0070] S4. Fill each of the conductive through holes 211 of the PCB with solder paste by dispensing, and then connect the LED device 3 to the PCB board 2 by reflow soldering or vacuum reflow soldering, so that the LED device 3 is electrically connected to the PCB. The conductive through hole 211 can be formed by drilling + electroplating copper.

[0071] For other contents of the LED module with thermal and electrical separation and the manufacturing method thereof described in the present invention, please refer to the prior art and will not be described in detail here.

[0072] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Therefore, any modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the technical solution of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A thermal and electrical separation LED module, characterized in that: It includes a radiator, a PCB board, and an LED device. A groove for the lower part of the PCB board to be embedded is provided on the top surface of the radiator, and a number of heat dissipation fins are convexly provided at intervals on the bottom surface. One end of the PCB board is horizontally provided with a connecting part. The horizontal cross-section of the groove is concave at this end. The groove is convexly provided with parallel first groove segments and second groove segments at this end. The connecting part is located between the first groove segment and the second groove segment and above the radiator. The LED device is installed on the top surface of the radiator and one end is located below the connecting part. The LED device includes a substrate and a light-emitting layer, a light conversion layer, and a light blocking layer provided on the top of the substrate. The light-emitting layer is provided at the end of the substrate away from the PCB board. The light conversion layer covers the light-emitting layer. The light blocking layer is annularly arranged around the sides of the light-emitting layer and the light conversion layer. An external bonding pad is also provided on the upper surface of the substrate. One end of the external bonding pad away from the light-emitting layer abuts against the lower surface of the connecting part. Two conductive through holes are vertically provided on the connecting part. The upper surface of the external bonding pad can seal the bottom openings of the two conductive through holes. It also includes an insulating layer that surrounds the side of the substrate.

2. The LED module with thermal and electrical separation according to claim 1, characterized in that: There is a gap between the side of the light blocking layer close to the connecting part and the side of the connecting part.

3. The LED module with thermal and electrical separation according to claim 2, characterized in that: The bottom surface of the substrate is provided with a bottom bonding pad.

4. The LED module with thermal and electrical separation according to claim 3, characterized in that: It also includes an adhesive layer that is located between the bottom bonding pad and the radiator. The adhesive layer is used to fix the substrate to the radiator.

5. The LED module with thermal and electrical separation according to claim 4, characterized in that: The radiator has a first end and a second end arranged oppositely. The LED is located between the groove and the edge of the second end. There is a spacing between the side of the insulating layer away from the PCB board and the edge of the second end.

6. The LED module with thermal and electrical separation according to claim 4, characterized in that: The PCB board is provided with a first convex part and a second convex part corresponding to the first groove segment and the second groove segment in sequence. The upper surfaces of the first convex part, the connecting part, and the second convex part are flush with the top surface of the PCB board. The lower surfaces of the first convex part and the second convex part are both flush with the bottom surface of the PCB board. The lower part of the first convex part is embedded in the first groove segment. The lower part of the second convex part is embedded in the second groove segment. The first convex part, the connecting part, and the second convex part are sequentially connected to form a U-shaped structure with an opening downward.

7. The LED module with thermal and electrical separation according to claim 5, characterized in that: First convex columns and second convex columns are convexly provided at intervals on the bottom of the groove. The PCB board is provided with a first limiting hole and a second limiting hole corresponding to the first convex column and the second convex column in sequence.

8. The LED module with thermal and electrical separation according to claim 7, characterized in that: The radiator is also provided with a first mounting hole that is located between the first convex column and the second convex column. The PCB board is provided with a second mounting hole that has the same diameter and is coaxial with the first mounting hole. The first convex column is located on the side of the first mounting hole close to the first end. The second convex column is located on the side of the first mounting hole close to the second end. A number of the heat dissipation fins are respectively distributed on both sides of the first mounting hole.

9. The LED module with thermal and electrical separation according to claim 7, characterized in that: The heat sink is also provided with a first positioning hole and a second positioning hole, both of which are close to the second end and are respectively located on both sides of the LED device, and the center line of the light-emitting layer coincides with the center lines of the first positioning hole and the second positioning hole.

10. A method for manufacturing a thermoelectrically separated LED module, for manufacturing the thermoelectrically separated LED module according to any one of claims 1 to 9, characterized in that: The following steps are involved: S1. First, the LED device is bonded by SMT bonding, and then the LED device is fixed on the top surface of the heat sink by thermal conductive glue; S2. Using insulating glue to form the insulating layer around the LED device; S3. Place the PCB board in the groove of the heat sink, and then press the PCB board downward to make the bottom surface of the PCB board close to the bottom of the groove, and at the same time, the lower surface of the connecting portion is close to the upper surface of the external solder pad of the LED device; S4. Fill each of the conductive through holes of the PCB board with solder paste by dispensing or spraying, and then connect the LED device to the PCB board by reflow soldering, so that the LED device is electrically connected to the PCB board.

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