CN102102862B

CN102102862B - Method for packing micro-volume multi-LED (Light-Emitting Diode) integrated unit

Info

Publication number: CN102102862B
Application number: CN201010543818XA
Authority: CN
Inventors: 吴坚; 李倩; 陈涛; 刘世炳
Original assignee: Beijing University of Technology
Current assignee: Beijing University of Technology
Priority date: 2010-11-12
Filing date: 2010-11-12
Publication date: 2012-05-30
Anticipated expiration: 2030-11-12
Also published as: CN102102862A

Abstract

The invention discloses a method for packing a micro-volume multi-LED (Light-Emitting Diode) integrated unit and a method for packing electrodes thereof, belonging to the field of LED manufacture, specifically relating to a method for packing LED lamps. A micro-volume LED integrated unit consists of base plates, connecting films, LED chips, a UV (Ultraviolet) adhesive, a photomask, a UV lamp, a silver conductive adhesive and thin leads. The five base plates which can be combined into a spatial three-dimensional microstructure are mutually connected by the connecting films; the LED chips are fixed on the base plates; the silver conductive adhesive is used for connecting electrode points of the LED chips needing to be led out with the thin leads; the UV adhesive is used for fixing a micro-space formed by the base plates; the photomask covers the three-dimensional microstructure formed by the base plates; a gold wire ball bonder is used for bonding wires on the LED chips; and the UV lamp is used for solidifying the UV adhesive and the silver conductive adhesive. The invention realizes high-strength LED illumination in a micro-volume and can regulate the optical characters of output lights. In addition, the invention also provides a power source package technique in the micro-volume.

Description

The method for packing of the long-pending many LED integrated unit of a kind of microbody

Technical field

The method for packing of the long-pending many LED integrated unit of a kind of microbody and electrode package method thereof belong to LED and make the field, are specifically related to the method for packing of LED lamp.

Background technology

After Edison in 1879 invented the carbon filament incandescent lamp, lighting engineering just got into a brand-new era.Incandescent lamp just has birth defects from that day that it comes out, and tungsten filament heating power consumption is big, and the frangible power consumption of bulb is big, and gets an electric shock easily.Though fluorescent lamp is more unfavorable to people's eyesight than incandescent lamp electricity saving and energy saving, the mercury in the fluorescent tube also is harmful to human body and environment.Yet that really cause lighting engineering generation qualitative change still is LED.

LED (Light Emitting Diode), light emitting diode is expected to become " the 4th generation light source "; With the traditional lighting compared with techniques, the difference of the maximum of LED is the difference of structure and material, and it is a kind of semiconductor that can electric energy be converted into visible light; The two-layer up and down electrode that is equipped with; There is conductive material the centre, and material that can be luminous is in the interlayer of two electrodes, and the color of light changes according to the difference of material character to some extent.LED is produced the light of superhigh intensity by the superconduction luminescent crystal; The heat that it sends seldom; Waste too many heat unlike incandescent lamp; Also produce toxic gas unlike fluorescent lamp because of high energy consumption, also damage easily unlike neon light requires high voltage, LED has been known as the environmental protection high-tech light source of a new generation by the whole world.

The LED illuminating product utilizes LED as the produced ligthing paraphernalia of light source exactly; At lighting field; The application of LED luminous product is just attracting common people's sight; LED must be a developing tendency in future as a kind of novel green light source product, and it is the novel illumination light source epoch of representative that 21 century will get into LED.

LED has the following advantages.

1. reliability is high, the life-span is long: LED is the solid cold light source, and anti-vibration not have the part become flexible in the lamp body, does not have the luminous easy burning of waiting for death, heat deposition, strolls shortcoming such as decline, and can reach 60000～100000h service life, grows more than 10 times than the conventional light source life-span.The LED stable performance, can be under-30～+ 50 ℃ of environment operate as normal.

2. luminous efficiency is high: the luminous efficiency of LED is higher 2～3 times than incandescent lamp at present.Along with the continuous development of LED technology, luminous efficiency all has raising significantly every year, can reach 100lm/W soon in recent years.

3. caloric value is low: LED uses cold light source, and dazzle is little, no infra-red radiation, and therefore, aspect heating, LED is little more many than the caloric value of incandescent lamp.

4. response speed is fast: because LED utilizes electronics-hole to bury in oblivion directly luminous phenomenon, therefore, the luminous response time is very short, usually below 100ms.

5. anti-collision: except optical characteristics, what conventional light source was used all is glass tube, therefore has shock-sensitive moving and frangible characteristics; LED does not use glass, therefore has anti-vibration and crash-resistant advantage.

6. volume is little, light: LED is the solid light source by semi-conducting material manufacturing, has little, the light characteristics of volume, therefore in design, can make full use of this point.

7. new green environment protection light source: LED uses cold light source, and dazzle is little, and is radiationless, do not send harmful substance in the use.The LED operating voltage is low, DC driven, and (single tube 0.03～0.06W), electric light power transfer are near 100%, and the equal illumination effect is more energy-conservation more than 80% than conventional light source for super low-power consumption.The LED environmental benefit is better, and the spectrum of LED almost all concentrates on visible light frequency band, and visual efficiency is up to 80%～90%, and the incandescent lamp visual efficiency of equal light efficiency is merely 10%～20%.Do not have ultraviolet ray and infrared ray in the spectrum, and discarded object is recyclable, does not pollute, do not contain mercury element, can safe touch, belong to typical green illumination light source.

In recent years, LED developed rapidly, and the luminous efficiency of LED increases by 100 times, and cost descends 10 times, and its development prospect has attracted the global illuminating product manufacturer's adding led light source and the market development.LED is described as the 21 century new light sources, be expected to become after incandescent lamp, fluorescent lamp, high-intensity gas discharge lamp the 4th generation light source.

The LED encapsulation technology encapsulates the LED luminescence chip exactly, processes the light source that can directly use.The mostly development and differentiation on the Discrete device packaging technical foundation of LED encapsulation technology, but very big particularity is arranged.Generally speaking, the tube core of discrete device is sealed in the packaging body, and main four protection tube cores of the effect of encapsulation and completion are electrically connected.The LED encapsulation then is the function that will accomplish the output signal of telecommunication, protection tube core operate as normal, output visible light; The design of existing electrical quantity and specification requirement; The design and the specification requirement of optical parameter are arranged, so the encapsulation technology of LED has very important influence for the characteristics of luminescence of final led light source again.

Conventional LED is packaged with bullet cut and surface attaching type.Bullet cut LED encapsulation is the led chip of in the cup of band lead frame, packing into; Encapsulate with the epoxy resin bullet cut on every side; Key dimension varies for the packaging appearance of

surface attaching type LED; But all be in the cavity of pottery or ester moulding, led chip to be installed, and then at cavity potting resin or silicones etc.

LED is expected to become " the 4th generation light source " with its remarkable advantage.But LED still exists following problem to need to improve:

(1) luminous quantity is low.LED is the micron-sized semiconductor of hundreds of, and the electric current through chip has tens milliamperes, and voltage is about 3V, and power consumption is very low, is about 100mW, although therefore luminous efficiency is high, luminous quantity is also little, and is lower than the power of conventional light source, a little less than the luminous quantity.

(2) selective color is few.The glow color of the LED that buys that uses as light source in the market is merely red, blue, green three looks basically, for the application scenario existence very big inconvenience of other colors of needs as light source.

(3) processing of electrode is particularly important in the LED encapsulation technology; General electrode package method is to use special led support; LED is fixed in the middle of the support, with the gold wire bonder bonding wire LED both positive and negative polarity is connected with electrode points in the support, and stent electrode is put outside extraction electrode.This method by number of applications in the led light source encapsulation technology; The problem of this method for packing is that the led support volume is excessive relatively; In volume and weight being had the harsh special space that requires, like fields such as aerospace and biological microminiaturizations, this method is very inapplicable just; Wasted the space greatly and increased weight, very science not.

(4) LED has very big prospect in the application of small space.At present; LED is widely used in the large tracts of land picture and text and shows conventional light source application facet such as full-color screen, state indication, sign illumination; And because LED has little, the light characteristics of the not available volume of conventional light source; In conventional light source implemented the small space of comparison difficulty, LED had huge value, can advance the development of the science and technology research that in the past received the restriction of conventional light source volume weight factor.Therefore, LED has prospect and necessity as the research of miniature very much.

Summary of the invention

Microminiaturization based on above-mentioned LED is used, and the present invention proposes a kind of method for packing of LED luminescence unit, in microbody is long-pending, realizes high-intensity LED illumination, and the optical characteristics of adjustable output light, and a kind of power package technology under microbody is long-pending is provided simultaneously.

To achieve these goals, the present invention designs the luminescence unit of the long-pending integrated a plurality of LED of a kind of microbody.

Theoretical foundation of the present invention: because the power consumption of LED is very low; So although luminous efficiency is high; Single led luminous quantity is also little, and in order to reach enough luminous quantities, the present invention proposes a kind of common luminous method with the increase luminous quantity of a plurality of led chips of on substrate, arranging.

In order in the microbody product space, to obtain high-strength light; The present invention proposes the integrated approach at a kind of LED; Arrangement led chip as much as possible in unit space, utilization mixed light principle, and the refraction of light, principle of reflection; The light that the design space structure is sent led chip converges as far as possible, finally obtains the light source that volume is little, intensity is high.

Based on above structural design,,, thereby realize the scalable of the long-pending light source optical characteristics of microbody as long as the light intensity of the long-pending interior red, green, blue three-color LED chip of control microbody just can synthesize versicolor light source according to the principle of three primary colours.

When the encapsulation microbody amassed light source, for good conserve space and weight, traditional led support was gained in weight also inapplicable again owing to it promptly increases the space; In order to save space and weight; The drawing of electrode can use thin wire and inapplicable electrode suppor can use conductive silver glue directly to cover an end of LED electrode points and thin wire, and the other end of thin wire is extraction electrode like this; Can be connected on other elements the volume and weight of the long-pending light source of the not extra increase microbody of this kind method.

Based on above-mentioned theory, the present invention adopts following technical scheme to realize.

Design the method for packing and the electrode package method thereof of the long-pending monochromatic LED integrated unit of a kind of microbody, utilize substrate, led chip, UV glue that a plurality of led chips are integrated in the microbody product unit, concrete preparation method is:

(1) connects four equirotal squares or rectangular on four limits of a foursquare substrate respectively through junctional membrane

The shape substrate forms cube shaped side's tube when four square or rectangular substrates are turned up simultaneously;

(2) mount more than one led chip respectively on the surface of said five substrates;

(3) be together in series or parallel through the spun gold bonding wire with the electrode of gold wire bonder said each led chip;

(4) use conductive silver glue to cover the total electrode and the thin wire of the led chip behind the serial or parallel connection simultaneously,, and use UV light irradiation conductive silver glue, conductive silver glue is solidified as extraction electrode;

(5) four square or rectangular substrates on four limits are turned up the formation cube simultaneously, UV glue is splashed in the cube to filling up, and use UV light irradiation UV glue, make its curing;

(6) surround the cube that constitutes by substrate with photomask.

The size of said five substrates is all 1mm * 1mm * 0.5mm; Or one of them is 1mm * 1mm * 0.5mm, and all the other four is 1mm * 2mm * 0.5mm.Said substrate adopts potsherd.Said junctional membrane adopts rubber

For the color LED integrated unit, also be to utilize substrate, led chip, UV glue that a plurality of led chips are integrated in the microbody product unit, specifically adopt following method:

(1) connects four equirotal square or rectangular substrates on four limits of a foursquare substrate respectively through junctional membrane, when four square or rectangular substrates are turned up simultaneously, form cube shaped side's tube;

(2) mount the led chip more than four respectively on the surface of said five substrates, led chip comprises redness, green and blue, perhaps dichromatism wherein;

(3) be together in series through thin wire with the electrode of gold wire bonder said homochromy led chip;

(4) use conductive silver glue to cover the total electrode and the thin wire of the led chip that is together in series of all kinds respectively simultaneously,, and use UV light irradiation conductive silver glue, conductive silver glue is solidified as extraction electrode;

(6) surround the cube that constitutes by substrate with photomask.

The size of said five substrates is all 2mm * 2mm * 0.5mm; Or one of them is 2mm * 2mm * 0.5mm, and all the other four is 2mm * 4mm * 0.5mm.

For the situation that comprises three kinds of color led chips, the quantity ratio of said redness, green and blue led chip is 7: 6: 7.

Said substrate adopts resin sheet.Said junctional membrane adopts high-temperature resistant membrane.。

The invention has the advantages that: the method through a plurality of led chips are integrated, improved luminous quantity greatly; The long-pending structure of microbody has realized led chip dense arrangement spatially, has reduced the size of light source greatly, has established the basis of the long-pending higher source luminance of microbody; The elargol of novelty cover the power package mode very rare can the long-pending light source of well maintained microbody light, little characteristics, do not have extra increase volume and weight; Electric current through regulating led chip can be controlled luminous intensity, thereby can send the light of various different optical characteristics comparatively easily, satisfies the light source requirements under the different condition, with using important meaning is arranged all for the scientific research of LED.The long-pending higher source luminance of this kind microbody that the present invention proposes will be fully developed talents in the small space field, promote the scientific research progress and the technical development of microtechnology industry.

Description of drawings

Fig. 1 a is the sketch map that is connected of substrate and junctional membrane in the embodiment of the invention 1;

Fig. 1 b is the arrangement sketch map of led chip in the embodiment of the invention 1;

Fig. 1 c is that led chip is connected the encapsulation sketch map in the embodiment of the invention 1 with electrode;

Fig. 1 d is the long-pending high brightness integrated LED luminescence unit shaping schematic view of microbody in the embodiment of the invention 1;

Fig. 1 e is the long-pending high brightness integrated LED luminescence unit finished product sketch map of microbody in the embodiment of the invention 1;

Fig. 2 a is the sketch map that is connected of substrate and junctional membrane in the embodiment of the invention 2;

Fig. 2 b is the arrangement sketch map of led chip in the embodiment of the invention 2;

Fig. 3 is the circuit catenation principle figure of led chip in the embodiment of the invention 2;

Fig. 4 is that led chip is connected the encapsulation sketch map in the embodiment of the invention 2 with electrode;

Fig. 5 a is the long-pending high brightness integrated LED luminescence unit shaping schematic view of microbody in the embodiment of the invention 2;

Fig. 5 b is the long-pending high brightness integrated LED luminescence unit finished product sketch map of microbody in the embodiment of the invention 2.

Among the figure: 1, potsherd substrate, 2, the rubber junctional membrane, 3, led chip, 4, UV glue; 5, photomask, 8, conductive silver glue, 9, thin wire, 10, the spun gold bonding wire; 11, resin substrate, 12, high-temperature resistant membrane, 13, the green light LED chip, 14, red LED chip, 15, blue-light LED chip.

The specific embodiment

Below in conjunction with Fig. 1 a～e embodiments of the invention 1 are specified.

Include potsherd substrate 1, rubber junctional membrane 2, led chip 3, UV glue 4, photomask 5, UV lamp, conductive silver glue 8 and thin wire 9.Wherein, Potsherd substrate 1 is the potsherd of five 1mm * 1mm * 0.5mm; Rubber junctional membrane 2 materials are the rubber thin skin; Potsherd substrate 1 connects shown in Fig. 1 a through rubber junctional membrane 2, with five corresponding respectively being fixed on five potsherds of potsherd substrate 1, shown in Fig. 1 b of high-power LED chip 3 that are of a size of 45mil; Use gold wire bonder with 10 pairs of led chip 3 bonding wires of spun gold bonding wire, five led chips are connected in series; Use conductive silver glue 8 covers the need extraction electrode and the thin wire 9 of led chip 3 simultaneously, shown in Fig. 1 c; Use UV lamp 4 irradiation conductive silver glues 8, make its curing; The application machine structure is turned up 1 of four ceramic substrate on four limits then, shown in Fig. 1 d; UV glue 4 is splashed in the cube that is made up of potsherd substrate 1,, make its curing with UV light irradiation UV glue 4; Surround the cube that constitutes by potsherd substrate 1 with photomask 5; Fig. 1 e is the long-pending many led light sources of high brightness of the microbody of processing.

Below in conjunction with Fig. 2 a～b, Fig. 3, Fig. 4, Fig. 5 a～b embodiments of the invention 2 are specified.

Include resin substrate 11, high-temperature resistant membrane 12, LED blue chip 15, LED red light chips 14, LED green glow chip 13, UV glue 4, photomask 5, gold wire bonder, UV lamp, conductive silver glue 8 and thin wire 9.Wherein, Resin substrate 11 is the resin sheet of five 2mm * 2mm * 0.5mm; High-temperature resistant membrane 12 materials are high-temperature resistant membrane; Like the PET film, resin substrate 11 connects shown in Fig. 2 a through high-temperature resistant membrane 12, and seven high-power blue-light LED chips that are of a size of 45mil 15, seven are of a size of the resin sheet that the high-power red LED chip 14 of 45mil, six high-power green light LED chips 13 that are of a size of 45mil are individually fixed in five 2mm * 2mm * 0.5mm; Fixing four chips on each resin sheet are shown in Fig. 2 b; With gold wire bonder the electrode of led chip is carried out bonding wire, the connected mode of led chip adopts connection in series-parallel to connect, color chip series connection of the same race, and the parallel connection of different colours chip, the connection in series-parallel sketch map is as shown in Figure 3; After bonding wire finished, use conductive silver glue 8 covers the need extraction electrode and the thin wire 9 of led chip simultaneously, and was as shown in Figure 4; Use UV light irradiation conductive silver glue 8, make its curing; Four resin sheets around the substrate 11 are turned up, formed cube structure, shown in Fig. 5 a,, need carefully prevent the short circuit of spun gold bonding wire or drop at this; UV glue 4 is splashed in the cube, use 7 irradiations of UV lamp that UV glue 4 is solidified; At last, wrap other faces except that light-emitting window with photomask 5, Fig. 5 b is and makes the long-pending many led light sources of high brightness of the microbody of accomplishing.

Above-mentioned photomask 5 adopts the black wrappage, like black gummed paper, pitch-dark.

In the present embodiment, also can the electrode of each color led chip be drawn respectively, control the luminous quantity of each color, thereby obtain the light source of different optical characteristic, realize that light source is controlled through the branch current of regulating the LED modules with different colors chip.In addition, can also optical element such as optical filter, lens etc. be installed at the light-emitting window place as required and satisfy the light source requirements under the specified conditions.

Claims

1. the method for packing of the long-pending monochromatic LED integrated unit of a microbody is characterized in that: utilize substrate, led chip, UV glue that a plurality of led chips are integrated in the microbody product unit, concrete preparation method does,

(6) surround the cube that constitutes by substrate with photomask.

2. the method for packing of the long-pending monochromatic LED integrated unit of a kind of microbody as claimed in claim 1, it is characterized in that: the size of said five substrates is all 1mm * 1mm * 0.5mm; Or one of them is 1mm * 1mm * 0.5mm, and all the other four is 1mm * 2mm * 0.5mm.

3. according to claim 1 or claim 2 the method for packing of the long-pending monochromatic LED integrated unit of a kind of microbody, it is characterized in that: said substrate adopts potsherd.

4. according to claim 1 or claim 2 the method for packing of the long-pending monochromatic LED integrated unit of a kind of microbody, it is characterized in that: said junctional membrane adopts rubber.

5. the method for packing of the long-pending color LED integrated unit of a microbody is characterized in that: utilize substrate, led chip, UV glue that a plurality of led chips are integrated in the microbody product unit, concrete preparation method does,

(6) surround the cube that constitutes by substrate with photomask.

6. the method for packing of the long-pending color LED integrated unit of a kind of microbody as claimed in claim 5, it is characterized in that: the size of said five substrates is all 2mm * 2mm * 0.5mm; Or one of them is 2mm * 2mm * 0.5mm, and all the other four is 2mm * 4mm * 0.5mm.

7. like the method for packing of claim 5 or the long-pending color LED integrated unit of 6 described a kind of microbodys, it is characterized in that: the quantity ratio of said redness, green and blue led chip is 7: 6: 7.

8. like the method for packing of claim 5 or the long-pending color LED integrated unit of 6 described a kind of microbodys, it is characterized in that: said substrate adopts resin sheet.

9. like the method for packing of claim 5 or the long-pending color LED integrated unit of 6 described a kind of microbodys, it is characterized in that: said junctional membrane adopts high-temperature resistant membrane.