CN105336834A - Circuit-structure-contained mirror-metal-based LED module, production method thereof, and application thereof - Google Patents

Abstract

The invention discloses a high-reflection metal-based LED module with a circuit structure, its application and its production method. It is a trapezoidal reflective cup array, and the upper surface of the metal substrate on both sides of each reflective cup is bonded with packaging electrodes and reflective circuits; gaskets, the gaskets are fixed on the bottom surface of the reflective cups, and pass through the circuit It is connected with the packaging electrode; the LED chip is connected with the upper surface of the pad; the reflective cup is provided with a packaging protection layer covering the LED chip, the pad and the circuit connection. Through the innovation of the circuit board preparation process of forming first and then bonding, the present invention can simultaneously prepare the circuit structure on the high-reflection metal-based packaging bracket to form a high-reflective metal-based packaging bracket with a circuit structure. The LED chip is placed on the In the reflector cup, mutual interference is avoided, and the light output efficiency of LED and the utilization rate of LED lamps are improved.

Description

A mirror-surface metal-based LED module with a circuit structure, production method and application thereof

technical field

The invention belongs to the technical field of LED lamps, and particularly relates to an LED module with a circuit structure and a high thermal conductivity double-sided metallized ceramic gasket, a mirror metal base or a nano high reflective coating metal base, an application and a production method thereof.

Background technique

The current traditional LED packaging bracket is mainly that LED particles are sealed in a bracket composed of a reflective cup with an inverted trapezoidal cross-section and plastic or ceramic + metal electrodes. As shown in Figure 1, there are two electrode pins extending from the left and right of the LED particles. outside the bracket. This traditional solution has complicated process, and because plastic is used as reflective material, on the one hand, it leads to low reflective efficiency; Overall cooling is poor. The packaged device with ceramic + metal structure has improved thermal conductivity, but its light efficiency, thermal conductivity and overall cost are all at a disadvantage. More importantly, when these devices are applied to lamps, it is necessary to prepare corresponding circuit boards, and use SMT equipment to carry out corresponding patching and welding of LED particles, which increases the complexity and cost of the industrial chain. In addition, due to the use of conventional metal-based circuit boards or other types of circuit boards, the heat dissipation path of LEDs is extended, or due to the extremely low thermal conductivity of the insulating layer of conventional circuit boards (high-end, PVD diamond-like high thermal conductivity circuit boards are extremely expensive ) prevents the heat energy of the LED from being dissipated smoothly, thereby reducing the light efficiency and reliability of the LED.

Another metal-based COB packaging device, as shown in Figure 2, uses thermoelectric separation and COB to package the LED device on the silver-plated aluminum substrate or even on the mirror aluminum substrate, which makes the light and thermal performance of the LED. Improvement, but most of them are targeted application designs, which cannot be applied to different types of lamps at the same time; metal-based COBs are mostly packaged on a plane, which causes mutual luminous interference between LED chips, resulting in waste of silica gel/phosphor materials. Increase its coating difficulty and affect its luminous performance. In fact, the luminous efficiency of products packaged with ordinary metal-based COB is even lower than that of the above-mentioned independently packaged SMD LEDs.

Although the conventional metal-based COB product solves the problem of the direct diffusion of LED heat to the metal substrate, it needs to be filled with thermal paste and then fixed on the metal heat sink with screws when it is used in the preparation of lamps, which increases the corresponding cost. Cost and thermal resistance, the heat dissipation effect is significantly reduced.

There is also a non-encapsulation LED, which has been coated with phosphor powder and has solderable electrodes during chip-level processing, but it still needs a good light, electricity, and thermal environment when manufacturing and applying lamps, and cannot meet the requirements of conventional chips at the same time. And the final product application of package-free LED.

Contents of the invention

Aiming at the technical problems of low light efficiency and high cost in the prior art, the present invention provides a highly reflective metal-based LED module with a circuit structure, its application and its production method, which can completely solve the above technical problems.

In order to solve the problems of the technologies described above, the technical solution adopted in the present invention is:

A kind of LED mold with mirror surface metal base or nanometer high reflective metal base with circuit structure

blocks, including

A highly reflective metal substrate, the highly reflective metal substrate has a reflective cup array with a trapezoidal cross-section, and the upper surface of the metal substrate on both sides of each reflective cup is bonded with a packaging electrode and a reflective circuit;

Gasket, the gasket is fixed on the bottom surface of the reflective cup, and is connected to the packaging electrode through a circuit; the upper and lower surfaces of the gasket are metallized, and the upper surface can be suitable for formal, vertical, and flip-chip structures. Silver paste, eutectic, reflow solder paste and other crystal-bonding forms of various medium and high-power LED chips;

an LED chip, the LED chip is connected to the upper surface of the spacer;

The reflective cup is provided with an encapsulation protective layer covering the LED chips, pads and circuit connections;

The LED chip is used in a vertical or flip-chip structure, and is fixed on the bottom of a mirror metal reflective cup or a metal + nanometer high reflective coating cup through the transition of a double-sided metallized high thermal conductivity insulating gasket by means of eutectic or soldering packaging form.

Further, the highly reflective metal substrate has an upper surface that can be partially welded or fully welded, and has a lower surface for soldering plating.

Further, the base material of the gasket is a high thermal conductivity insulating ceramic layer, and the high thermal conductivity insulating ceramic layer has two upper and lower layers of metallized surfaces for welding.

Further, for a flip-chip chip, the upper surface of the spacer can separate the insulating groove.

Further, the lower surface of the spacer is eutectically or reflow welded with the bottom surface of the reflective cup.

Further, the upper surface of the gasket has a eutectic soldering or solder paste soldering layer and gold wire (or silver wire or copper wire or aluminum wire) bonding that can be used to form an electrical connection between the LED chip and the package electrode. layer.

Further, the LED chip is soldered and connected to the upper surface of the gasket through eutectic paste/silver glue/solder paste with high thermal conductivity.

Furthermore, the modules can be cut into square, circular, rectangular or irregular shapes to finally meet the design and application of LED lighting fixtures.

A method for producing a mirror metal-based LED module with a circuit structure, comprising the steps of:

(1) After the high thermal conductivity mirror metal sheet is treated with a weldable coating on the upper surface and the back, an array of reflective cups with a trapezoidal (or bowl) cross-sectional shape is punched out; or the upper and lower surfaces of the high thermal conductivity metal sheet are weldable. , first punch out an array of reflective cups with a trapezoidal (or bowl-shaped) cross-sectional shape, and then perform local high-reflective nano-coating treatment to form the package module body;

(2) Silver-plate the surface of the conductor layer of the thin-film circuit substrate, prefabricate the shape of the packaging electrode and the circuit, and then attach the circuit and the packaging electrode to a predetermined position on the upper surface of the metal substrate;

(3) Prefabricate the high thermal conductivity insulating ceramic layer into a gasket of a certain size, the upper and lower surfaces of the gasket can be welded and metallized, and the lower surface and the bottom surface of the reflective cup can be eutectic or reflow welded;

(4) The upper surface of the spacer is welded and connected to the LED chip, and the LED chip is electrically connected to the packaging electrode, and then packaged and protected.

Further, the prepared LED module is treated with insulating coating or parylene coating for secondary electrical protection.

Compared with prior art, the beneficial effect that the present invention has is:

1. Modular and self-contained circuit, easy to design, use and install.

2. Using thermoelectric integration technology, the LED chip is welded and fixed on the surface of the metal layer of the highly reflective metal substrate 1 through high thermal conductivity insulating gasket, combined with the body and the metal solder layer to connect with the radiator, the heat dissipation is smooth and effective, and there is no heat dissipation bottleneck effect , thereby reducing the junction temperature, improving the light efficiency and the utilization efficiency of the LED.

3. The independent high-reflection mirror reflector cup significantly improves the light output efficiency of the LED; the phosphor/silicone material is uniform, economical, and reliable in quality (the temperature rise of the LED chip and phosphor is low, and there is almost no denaturation, degradation, discoloration and drift, and light attenuation).

4. When the module is installed in the lamp, the surface of the module is distributed with a large area of mirror surface and a partial silver-plated circuit surface, so it hardly absorbs the light emitted by the LED; coupled with the configuration and use of peripheral reflective materials, it can be more Greatly improve the overall luminous efficiency of the lamp.

5. The manufacture of lamps does not involve SMT equipment and SMD LED package bracket materials, which simplifies the structure of the industrial chain and reduces costs.

6. The invention is especially suitable for high-power and high-heat-density lamps, as well as medium and small power lamps that reduce junction temperature and improve light efficiency. Compared with SMDLED and COBLED, the light efficiency can be increased by 20% when using the same LED chips and phosphor materials. %, the temperature rise is reduced by 25 degrees Celsius, and the cost is saved by more than 15%.

7. Compared with the production method of welding vertical or flip-chip LED devices on ordinary circuit boards, the present invention can effectively improve the heat dissipation effect of LEDs and obtain higher packaging light efficiency;

Description of drawings

1 is a schematic diagram of the three-dimensional structure of a mirror metal-based LED module with a circuit structure of the present invention;

Fig. 2 is a cross-sectional structural schematic diagram of Fig. 1;

Fig. 3 is a structural schematic diagram of a mirror metal-based LED module with a circuit structure applied to a lamp according to the present invention;

Fig. 4 is a schematic diagram of a three-dimensional structure of a spacer suitable for flip-chip use.

In Fig. 1-Fig. 4, 1. Mirror metal substrate; 11. Reflective cup; 12. Encapsulation electrode; 2. Gasket; 21. High thermal conductivity insulating ceramic layer; 22. Flip-chip insulation groove; . Package protective layer; 5. Radiator; 6. Metal solder layer.

detailed description

In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be described in detail below in conjunction with the accompanying drawings and specific embodiments.

As shown in Figure 1 and Figure 2, a highly reflective metal-based LED module with a circuit structure, including

Mirror metal substrate (or ordinary metal+nano-reflective coating substrate) 1, the mirror metal substrate has a reflective cup array with a trapezoidal cross-section, and the upper surface of the mirror metal substrate on both sides of each reflective cup 11 is bonded with packaging electrodes 12 and Reflective circuit;

Gasket 2, the gasket 2 is fixed on the bottom surface of the reflective cup 11, and connected to the packaging electrode 12 through a circuit;

The LED chip 3 is connected to the upper surface of the gasket 2;

The reflective cup 11 is provided with an encapsulation protection layer 4 covering the LED chip 3, the gasket 2 and the connection of the circuit.

When the above-mentioned LED module is applied to LED lamps, the light emitted passes through the upper surface of the mirror metal substrate 1, the mirror surface inside the reflector cup 11, the reflective surface layer of the silver-plated circuit, and the reflective surface of the lamp cavity designed on the periphery of the module. After comprehensive optical design processing, the light efficiency is improved.

The mirror metal substrate 1 has a partially weldable or fully weldable upper surface, and has a lower surface for welding coatings, such as electroplating/electroless nickel plating, tin and other medium and low temperature welding coatings, so as to be compatible with weldable metals. The radiator is welded to facilitate heat dissipation.

The thickness of the mirror metal substrate 1 is uniform, and the performance form is that the bottom surface of the reflective cup 11 protrudes downward from the lower surface of the mirror metal substrate 1 .

The base material of the gasket 2 is a high thermal conductivity insulating ceramic layer, and the high thermal conductivity insulating ceramic layer has two upper and lower metallized surfaces for welding.

As shown in Fig. 4, the upper surface of 21 should be suitable for a chip with a positive or vertical structure; in order to be suitable for a flip chip, the upper surface of the gasket 2 can be divided into two parts by an insulating groove 22, and the bottom surface of the long groove 22 is a high thermal conductivity insulation The upper surface of the ceramic layer 21.

The gasket 2 is eutectically or reflow welded with the bottom surface of the reflector cup 11 through its lower surface.

The upper surface of the pad 2 has both a wire ball soldering layer (gold, silver, aluminum, copper wire).

The LED chip 3 is soldered and connected to the upper surface of the pad 2 through high thermal conductivity eutectic paste/silver glue/solder paste.

An application of a highly reflective metal-based LED module with a circuit structure, which can be cut into square, circular, rectangular or special shapes to form a shape that finally meets the design application of LED lighting fixtures.

A method for producing a highly reflective metal-based LED module with a circuit structure, comprising the steps of:

(1) A mirror metal substrate 1 is formed after the high thermal conductivity metal thin plate undergoes reflective treatment on the front, part or all of it can be welded, and the back can be welded and coated, and then a plurality of reflective cups 11 with a trapezoidal cross-sectional shape are punched out on the mirror metal substrate 1 , a plurality of optical cups 11 are arranged in an array. In this embodiment, as shown in FIG. 1, it is a rectangular array to form a package module body, which can realize thermoelectric separation, good heat conduction, maximized light output and cost optimization functions, and can avoid LED chips. Mutual light interference increases the amount of LED phosphors and silica gel used (compared to COB); improves efficiency, saves packaging materials and eliminates all processes and materials for mounting and welding LED devices on circuit boards (compared to COB) SMDLED).

(2) Silver-plate the surface of the conductor layer of the thin-film circuit substrate (its upper surface is a composite electrode material that can be "wire-bonded" and solderable, and has an insulating adhesive layer), so that it has conventional While welding and conduction (insulation) functions of the circuit board, it meets the ball welding requirements of the LED package, and at the same time realizes the light reflection function required for the application of the lamp, and then uses cold cutting (die cutting, stamping, low temperature laser, etc.) Cutting or stamping, etc., pre-form the conductor layer of the film circuit base material after silver plating into the shape required for the packaging electrode 12 and the circuit, and then through the placement machine positioning, hot pressing and medium temperature curing process, the circuit and packaging electrode 12 is accurately and firmly attached to a predetermined position on the upper surface of the mirror metal substrate 1 .

(3) Using laser cutting or numerical control scribing, the high thermal conductivity insulating ceramic layer (such as aluminum nitride, aluminum oxide, etc.) is prefabricated into a gasket 2 of a certain size, and the upper and lower surfaces of the gasket 2 are weldable metal Chemical treatment (such as: silver plating, nickel plating, etc.) to form a new type of gasket with conductive surface and high thermal conductivity, and the lower surface of the gasket 2 and the bottom surface of the reflector 11 can be eutectic or reflow welded;

(4) The upper surface of the gasket 2 is welded and connected to the LED chip 3 through a high thermal conductivity eutectic paste/or silver glue or solder paste, and an electrical connection is formed between the LED chip 3 and the packaging electrode 12; A certain line width interval is reserved on the edge of the upper surface for future gold or silver wire bonding to form a ball bonding layer for electrical connection between the LED chip 3 and the packaging electrode 12 .

(5) Finally, it is packaged and protected with fluorescent powder mixed with silica gel or remote fluorescent film.

For the above-mentioned prepared LED lighting modules, according to the insulation level requirements of different types of LED lighting products, if necessary, use insulating coating or parylene coating for secondary electrical protection treatment to ensure good light output, Under the premise of reflective function, the product's withstand voltage and antistatic level are improved.

The above-mentioned mirror metal-based LED modules containing conductive circuit structures after protection treatment can also be cut into square, round, rectangular or special-shaped by using V-CUT slotting machine and splitting machine, or other cutting equipment Wait for the shape that conforms to the design and application of the final LED lighting fixture, and assemble the LED lighting fixture for product application.

The circuit board preparation process innovation of forming first and then laminating can simultaneously prepare the circuit structure on the above-mentioned mirror metal-based packaging bracket to form a mirror metal-based packaging bracket with a circuit structure, and its upper surface has been prefabricated and integrated. LED conductive circuit, compared with traditional SMT LED packaging devices, does not need to use aluminum-based circuit boards or other types of circuit boards when preparing LED lighting fixtures, does not need to use SMT equipment for patch processing, and does not need this link other materials.

When the LED module in the present invention is applied to LED lamps, because of its own structural design of a series-parallel circuit, the output terminals of the power supply module of the LED lamp can be directly welded to the two poles of the circuit and drive the LED packaging module. .

Can be packaged and welded with high thermal conductivity and insulation composite ceramic materials, and multi-functional composite circuit substrates. Aluminum, stainless steel) foil circuit base material for innovative application of surface treatment such as silver plating (gold, nickel, titanium, etc.); multifunctional refers to a series of circuits such as solderability, conduction, insulation, high thermal conductivity, and bonding , The necessary functions of packaging electrodes.

As shown in Figure 3, the heat energy generated by the LED chip in the module can be dissipated directly through the mirror metal material with high thermal conductivity and the metal radiator 5 connected with the metal solder layer 6 on the back, that is, the LED chip is shared. The thermal resistance of crystal welding is very small, which makes the LED junction temperature lower than that of ordinary packaging applications.

The invention integrates the optimization of LED photoelectric and thermal environment, and the application-type packaging circuit substrate that can be manufactured and used in a modular manner, so that it can be directly used in the manufacture of lamps; and fully simplifies the industrial chain process——banning the traditional SMDLED and COB packaging applications The processes, links and materials required in the process, such as packaging bracket materials, circuit boards for mounting LED devices, SMT processes and materials, heat dissipation and fixing structural parts, and thermal conductive silicone grease, will have a great impact on the application technology development and product cost performance of the entire industry. Optimization and other aspects have had an important and positive impact.

The above embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and the protection scope of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent replacements to the present invention within the spirit and protection scope of the present invention, and such modifications or equivalent replacements should also be deemed to fall within the protection scope of the present invention.

Claims (10)

1., with a high reflecting metal base LED module for circuit structure, it is characterized in that, comprise

Described high reflecting metal substrate has the reflector array that cross section is trapezoidal (or bowl-type), and the upper surface of the metal substrate of each reflector both sides is all fitted with encapsulated electrode and reflective circuit;

Pad, described pad is fixed on the bottom surface of described reflector, and is connected with described encapsulated electrode by circuit;

LED chip, described LED chip is connected with the upper surface of described pad;

The packaging protection layer of coated LED chip, pad and circuit junction is provided with in described reflector.

2. the high reflecting metal base LED module with circuit structure according to claim 1, is characterized in that, described high reflecting metal substrate has the upper surface that process can be welded or all can be welded in local, and has the lower surface for welding coating; The consistency of thickness of described high reflecting metal substrate.

3. the high reflecting metal base LED module with circuit structure according to claim 1, it is characterized in that, the base material of described pad is high heat conductive insulating ceramic layer, and described high heat conductive insulating ceramic layer has the two-layer surface for welding through metalized up and down.

4. the high reflecting metal base LED module with circuit structure according to claim 3, is characterized in that, the upper surface of described pad, when it is when encapsulating the LED chip of vertical stratification or vertical thin-film structure, is the whole piece electrode of connected state; When encapsulating inverted structure LED chip, its upper surface forms two electrodes be electrically separated from each other by fluting.

5. the high reflecting metal base LED module with circuit structure according to claim 1, is characterized in that, described pad passes through bottom surface eutectic or the reflow soldering of its lower surface and reflector.

6. the high reflecting metal base LED module with circuit structure according to claim 1, it is characterized in that, the top surface edge of described pad has the spun gold, filamentary silver or the copper that can be used for forming electrical connection between described LED chip and encapsulated electrode/aluminium wire ball bonding layer.

7. the high reflecting metal base LED module with circuit structure according to claim 1, is characterized in that, described LED chip is welded to connect by the eutectic cream/elargol/tin cream of high heat conduction and the upper surface of pad.

8. with an application for the high reflecting metal base LED module of circuit structure, it is characterized in that, described module can cut into square, circular, rectangle or abnormity forms the shape finally meeting LED illumination lamp design ap-plication.

9. a production method for LED module according to claim 1, is characterized in that, comprises the steps:

(1) high heat conduction mirror metal thin plate can weld coating process through upper surface local, the back side, stamps out and has the array that cross sectional shape is the reflector of trapezoidal (or bowl-type); Or after high-thermal conductive metal thin plate upper and lower surface does solderability process, first stamp out and there is the array that cross sectional shape is the reflector of trapezoidal (or bowl-type), then do the high reflective nano coating process in local, form package module body;

(2) by thin film circuit base material conductor layer electroplate (or gold, nickel) process, be prefabricated into encapsulated electrode (bonding spun gold, filamentary silver or copper wire aluminium wire) and circuitry shapes, then circuit and encapsulated electrode be fitted on the precalculated position of mirror metal upper surface of base plate;

(3) high heat conductive insulating ceramic layer is prefabricated into a certain size pad, two surfaces up and down of described pad can weld metal process, and can eutectic or reflow soldering by the bottom surface of its lower surface and reflector;

(4) upper surface of described pad and LED chip are welded to connect, and form electrical connection, then carry out packaging protection to it between LED chip and encapsulated electrode.

10. the mirror metal base LED module with circuit structure according to claim 9, is characterized in that, the described LED module prepared carries out insulating coating for secondary electic protection or the process of Parylene coating.