A kind of manufacturing approach of adopting surface mounted LED module
Technical field
The present invention relates to a kind of production method of making the adopting surface mounted LED module.
Background technology
Development along with the illumination LED technology; For the lighting source of conventional incandescent, Halogen lamp LED type; LED has had obviously energy-conservation, reliable, long-lived advantage, and can reach the illumination performance of fluorescent lamp gradually, for example light efficiency and color rendering index, life-span aspect.Therefore, in the global range, the development of illumination LED is in the ascendant, and the led light source annual production also progressively increases,
Compare traditional light source, led light source has some tangible characteristics, usually on volume; Led light source all is to be unit with single chip (chip), has electrode, fluorescent material, encapsulating structure or the like, has smaller volume and less luminous flux; If need to form suitable lighting; The then unavoidable module that uses a plurality of led light sources to form the array form can be integrated volume, structure form and unified power supply on the one hand, must reach enough luminous fluxes on the other hand.These characteristics are just very outstanding at general illumination, room lighting: more common way, exactly with the led light source of complete package be arranged in fixing on the substrate, be communicated with, formation can the luminous LED module of integral body, is assembled into complete light fixture with this module again.If the light fixture form is bigger, the luminous flux higher (more than 1000lm) that single light fixture is required, the quantity of then single LEDs light source is inevitable very many, and is very obvious when particularly adopting middle low power (like 10mil) encapsulated LED light source.So the manufacturing process processing procedure of entire module is very long, must accomplish the encapsulation of single LEDs light source earlier, just be welded on and process module on the substrate.
To this problem, it is COB (chip-on-board) technology that one type of way is arranged, and after soon chip is fixed on the substrate, carries out routing again and connects, and applies fluorescent material, covering protection glue etc. at last.This type mode has been exempted the packaging body of single led light source; But brought new problem: led chip is fixed in after the substrate, always needs to be directed against the single processing such as routing, dusting of carrying out, and considers the intensity of metal wire; Its failure rate is higher, handles and causes technology hidden danger more.And the manufacturing process time is oversize, and the quantity of getting the raw materials ready is many, so Material Cost of making and time cost all are difficult to reduction.
So when the large-scale production of LED module, the technological process that always is difficult to avoid encapsulating structure to bring too high cost and numerous and diverse material to bring is oversize, and the not high problem of reliability.
Summary of the invention
Main purpose of the present invention is to provide a kind of manufacturing approach of adopting surface mounted LED module, consumes the too much Material Cost problem of material of encapsulation when solving the large-scale production of LED module; Oversize time cost problem of manufacturing process time when another purpose is to solve by the large-scale production of LED module; A purpose is to solve and produces the LED module that finishes not high, the hidden danger with processing technology of single LEDs light source reliability on it again:
A kind of manufacturing approach of adopting surface mounted LED module may further comprise the steps:
Get the raw materials ready: the led chip of flip chip structure is provided, and the one side of this led chip has metal electrode, and the surface spacing of said metal electrode is not less than 80 μ m;
Layout: a plurality of said led chips are placed in the middle of the braid, and its metal electrode of said led chip is positioned at the bottom of said braid accommodation space, and the exiting surface of said led chip is positioned at said accommodation space opening part;
Mount: adopt vacuum slot with the sucking-off from said braid of said led chip, place on the pad of a substrate; Said metal electrode is relative with said pad, and the exiting surface of said led chip up; And
Fixing: with said pad and the corresponding fixing and connection of metal electrode.
As the improvement of present technique scheme, can aspect following, embody:
In the preferred embodiment, the said step that mounts takies, and said braid places on the chip mounter of an auto-feed, and controlled feeding one by one.
In the preferred embodiment, said mounting in the step established tin cream in advance on the said pad, and the metal electrode of said led chip utilizes the surface tension of said tin cream temporarily to be fixed in said substrate.
In the preferred embodiment, adopt reflow machine that the tin cream between said metal electrode and the pad is solidified in the said fixing step.
In the preferred embodiment, said reflow machine comprises following flow process:
Send plate: the said substrate that will mount is positioned on the transport tape, and said transport tape is controlled and advance;
Preheating: the secondary solvent in the said tin cream is volatilized;
Samming: the scaling powder in the said tin cream of activation, and evaporating surplus moisture;
Reflow: the said tin cream of fusion makes it to fill between said metal electrode and the pad zone and with the two connection;
Cooling: make the temperature of said tin cream, metal electrode, pad be reduced to chilling temperature.
In the preferred embodiment, said pad has a plurality of on said substrate, and said tin cream adopts the mode of silk screen printing to be attached to said pad.
In the preferred embodiment, after said fixing step is accomplished, with the exiting surface covering fluorescent film of said led chip,
Said fluorescent film is corresponding one by one with said led chip, mounts separately.
In the preferred embodiment, after said fixing step is accomplished, with the exiting surface covering fluorescent film of said led chip,
Said fluorescent film is the form of a monolithic film membrane, is covered in the surface portion of said led chip together with its place substrate.
In the preferred embodiment, after said fixing step was accomplished, with the exiting surface covering fluorescent film of said led chip, said fluorescent film adopted the liquid mode that sprays directly to be sprayed at the exiting surface of said led chip, together with the said substrate surface of its homonymy.
In the preferred embodiment, said led chip is the blue light person for sending visible light, and its wave-length coverage is 440-470nm.Also can be the person that sends the ultraviolet light, its wave-length coverage is 240-355nm.
In the preferred embodiment, said mounting in the step, other being provided with of said pad has the auxiliary colloid that said led chip bottom temporarily is fixed in said substrate surface.
The beneficial effect that the present invention brings is:
1. will cover the mode that brilliant led chip directly adopts braid to load, avoid the encapsulation of single led light source, save encapsulation material and the packaging technology time and the production line of single led light source;
2. what draw with vacuum slot is the exiting surface of led chip, its geometric properties high conformity, and the situation that the adhesive that does not have irregular form to bring was lost efficacy, its paster failure rate is low, and the location is accurately;
3. the led chip of braid formula, all paster techniques can be continued to use existing SMT equipment, need not make the input of additional hardware, have avoided the cost and the process time of packaging line, and the realization of its volume production is easier to;
4. after the led chip of flip chip structure is mounted on substrate, be easy to realize the stroke of fluorescent film, can use the mode of integral spray; Realize that in large area fluorescent material applies; Spraying equipment can not touch led chip, and its process time is short, the hidden danger that does not have contact process to bring.
Description of drawings
Embodiment is described further the present invention below in conjunction with accompanying drawing:
Fig. 1 is led chip 10 end views of the used flip chip structure of the embodiment of the invention one;
Fig. 2 is that embodiment one led chip braid step receives the form of back led chip 10 in braid 20;
Fig. 3 is the vertical view of embodiment one braid 20;
Fig. 4 is the state that embodiment one mounts step;
Fig. 5 is another state that embodiment one mounts step;
Fig. 6 is the vertical view after embodiment one fixing step finishes;
The end view of Fig. 7 state shown in Figure 6;
Fig. 8 is that embodiment one mounts a step dusting step state diagram afterwards;
Fig. 9 is the state diagram that the embodiment of the invention two mounts step;
Figure 10 is that embodiment two mounts the step back dusting step state diagram that finishes.
Embodiment
Embodiment one:
Shown in Figure 1; The led chip 10 that covers crystalline substance (Flip-chip) structure that the present invention utilized, its main body 10 is the semi-conducting material part, the below is the positive and negative metal electrode that constitutes ohmic contact with main body 10; In the plane below main body 10, metal electrode 13 spacing G1 each other is 80 μ m; The led chip of this type of flip chip structure, the metal electrode 13 of light-emitting area 12 and current-carrying part is positioned at the two sides of main body 10, mutually noninterfere, its luminous efficiency is higher.
As shown in Figures 2 and 3, led chip 10 is put into braid 20 one by one, each led chip occupies an accommodation space 23, and is independently of one another; And the metal electrode 13 of led chip 10 is positioned at accommodation space 23 bottoms; Exiting surface 12 is positioned at the opening part of accommodation space.Insert accommodation space when led chip 13 and finish, the opening part of braid 20 has diaphragm 21 with accommodation space 23 sealings, thinks protection.Braid 20 has location hole along its length direction, makes things convenient for mechanisms such as the ratchet extracting of braider and drive it to advance, and realizes auto-feed one by one.This braid of present embodiment is applicable to the chip mounter of all patch products, has good versatility.
Like Fig. 4 and shown in Figure 5, mount two states of step respectively; After braid 20 is installed on the automatic placement machine, again chip mounter is loaded substrate 40 to be mounted; Vacuum slot 30 stretches in the accommodation space, touch the exiting surface 12 of led chip 10 after, with the attitude sucking-off, this is a sucking-off state shown in Figure 4 with it; Move to pad 41 tops of substrate 40 again, wherein pad 41 is final and metal electrode 13 corresponding person one by one, has had the tin cream 42 of silk screen printing on the while pad 41; Pad 41 clearance G 2 also are 80 μ m.This is a paster state shown in Figure 5.After state shown in Figure 5, utilize the tension force of tin cream 42 itself, it is temporary transient fixing that metal electrode 13 and pad 41 are able to, and can be because of air-flow, rock and arbitrarily dislocation.
After this, tin cream 42 has passed through following steps at reflow machine:
Send plate: the substrate 40 that will mount is positioned on the transport tape, and transport tape is controlled and advance;
Preheating: the secondary solvent in the tin cream 42 is volatilized;
Samming: the scaling powder in the activation tin cream 42, and evaporating surplus moisture;
Reflow: fusion tin cream 42 makes it to fill between metal electrode 13 and the pad 41 zone and with the two connection;
Cooling: make the temperature of tin cream 42, metal electrode 13, pad 41 be reduced to chilling temperature.
After accomplishing said process, like Fig. 6 and shown in Figure 7, the led chip 10 that has mounted and fixedly finished, metal electrode 13 is fixed by solid-state tin cream 42 with pad 41 and is kept being communicated with.Tin cream 42 has relied on self tension force with metal electrode 13 pulling contrapositions before solidifying.So, substrate 40 has fixed led chip 10, and all led chip 10 connects according to the circuit of its pad 41 on the substrate 40, has constituted a complete module, can integral body light through inserting power supply.
What present embodiment adopted is 455nm blue-light LED chip 10; Need entire module to realize the white light output of 4000K colour temperature; So, also must carry out fluorescent material and apply module, present embodiment adopts the mode of liquid spraying; Fluorescent material directly is sprayed at the exiting surface of led chip 10, together with the said substrate surface of its homonymy.Pass through suitable baking again, make led chip 10 exiting surface 12 surfaces, with and the side, one deck fluorescent film 12 is all arranged, so the led chip 10 that whole base plate 40 is fixed can entire body send white light, reach the requirement of Gao Guangtong illumination.
It is thus clear that; To cover the mode that brilliant led chip 10 directly adopts braid to load; Have tangible characteristics; Make the manufacturing process of whole LED module avoid the encapsulation of single led light source, finally do not need single encapsulation just can all led chips 10 fixed and be communicated on the substrate 40, saved encapsulation material and the packaging technology time and the production line of single led light source; And, with the chip mounter of vacuum slot 30, absorption be the exiting surface of led chip 10, its geometric properties high conformity, the situation that does not have adhesive that irregular form brings to lose efficacy, the out-of-flatness face of fluorescent material for example, so its paster failure rate is low, the location accurately; Moreover when the led chip 10 that has used the braid formula, all paster techniques can be continued to use existing SMT equipment, need not make the input of additional hardware, have avoided the cost and the process time of packaging line, and the realization of its volume production is easier to; At last, after the led chip 10 of flip chip structure is mounted on substrate 40, be easy to realize the stroke of fluorescent film; Can use the mode of integral spray, realize that in large area fluorescent material applies, spraying equipment can not touch led chip 10; Its process time is short, the hidden danger that does not have contact process to bring.
Embodiment two:
Like Fig. 9, Figure 10, two state diagrams of the embodiment of the invention two:
Present embodiment is compared with embodiment one, and different is, in mounting step; Has auxiliary colloid 45 between substrate 40 its pads 41; These auxiliary colloid 45 effects are that when led chip 10 volumes were big, the tension force of depending merely on tin cream 42 was difficult to led chip 10 temporarily is fixed in substrate; Auxiliary colloid 45 just makes led chip 10 and pad 41 relative accurate and stable as temporary parts, even also attitude misalignment can not take place through reflow soldering.
What another were different is, after led chip 10 fixing step finish, the exiting surface of led chip 10 is covered fluorescent film 50; This fluorescent film is the form of a monolithic film membrane, and so moulding separately is can be directly with suitable pressure and binding agent; Make fluorescent film 50 integral body be covered in the surface portion of led chip 10 together with its place substrate 40, this mode has further shortened the molding time of entire module, does not need spraying; Need not toast yet and wait for its curing, so have very technological process fast.
It is thus clear that this mode that directly led chip 10 usefulness chip mounters is fitted in substrate 40 applies fluorescent material to large tracts of land and has tangible facility, makes its available several different methods moulding fluorescent film effectively.
The above is merely preferred embodiment of the present invention, so can not limit the scope that the present invention implements according to this, the equivalence of promptly doing according to claim of the present invention and description changes and modifies, and all should still belong in the scope that the present invention contains.