Background technology
LED can be luminous energy by electric energy conversion expeditiously, and has low-power consumption and the longer features such as service life.Therefore, LED not only can be applicable to display unit, also may be used in lighting.In recent years, LED is widely applied in various lighting fields as a kind of novel light source.
At present, for traditional LED packaging, be generally that LED chip is matched and used with mounting bracket, then they are fixed on aluminum base plate together.Afterwards, aluminum base plate carries out hot link with heat sink again.Yet this preparation method can produce the shortcoming that thermal resistance is higher.In order to reduce thermal resistance, the encapsulating structure of another main flow be by LED chip directly and substrate coordinate, carry out hot link with heat sink more afterwards.In this case, LED chip can be placed in the groove of being located at substrate surface, then by scolder, connect such as tin cream etc.Tin cream can form concordant with substrate surface, also can form the arc surface that protrudes from substrate surface.
Patent documentation CN202487662U discloses a kind of LED encapsulating structure, and it comprises base plate for packaging, is located at the LED chip on this base plate for packaging, and is covered in the packaging plastic on base plate for packaging and LED chip.Wherein, between LED chip and packaging plastic, be also provided with hemispheric lens.Here, base plate for packaging is generally hard substrate, for example, adopt metal or ceramic substrate.
Patent documentation CN202474038U discloses a kind of LED support type encapsulating structure, and it comprises lead frame and LED chip.In the upper and lower both sides of lead frame, be respectively arranged with encapsulating housing and lower encapsulating housing.LED chip is arranged in encapsulating housing, and the pin of LED chip is connected on lead frame.In upper encapsulating housing, be also provided with the upper packaging plastic being covered on LED chip, and in lower encapsulating housing, be provided with lower packaging plastic.For this LED device, it in use needs to be welded on substrate to use.Therefore, the complex process of the method, conforming product rate is lower.
As can be seen from above, existing LED encapsulation is generally to coordinate the hard substrates such as aluminium base, ceramic substrate to use together LED chip or LED device, and the encapsulating structure of gained is comparatively complicated.In addition, from LED chip, to heat sink, there is sandwich construction, cause existing larger thermal resistance.In addition, traditional encapsulating structure is applicable to adopting blue chip points of engagement adhesive process scheme more, and its technique is loaded down with trivial details, and conforming product rate is lower.
Therefore, in this area, wish to address the above problem for LED encapsulating structure, especially White-light LED package structure.
Summary of the invention
For above-mentioned technical problem, the present invention aims to provide a kind of LED package assembling, and it can reduce production costs effectively.In addition, the present invention it would also be desirable to provide a kind of LED package assembling, and wherein the substrate in this LED package assembling is flexible, and substrate is simple in structure, makes formed thermal resistance lower.
According to the present invention, a kind of LED package assembling is provided, comprising: flexible base, board, is wherein formed with line layer; Setting is arranged on the reflector layer in the first side of described flexible base, board; Be arranged on the LED chip on described flexible base, board, the electrode of described LED chip is electrically connected to described line layer through described reflector layer; Be arranged on the protective layer in the second side of described flexible base, board.
According to LED package assembling of the present invention, especially can send the LED package assembling of white light.Yet, those skilled in the art will appreciate that LED package assembling according to the present invention also can send the light of other color after the necessity of having carried out knowing is revised.
In one embodiment, described LED chip is White-light LED chip.In this case, described protective layer can be polymer material layer, is especially the polymer composite layer containing titanium oxide.Especially, described LED chip is white light LEDs flip-chip, and its end face and side are surrounded by hemispherical lens.
In another embodiment, described LED chip is blue-ray LED flip-chip.The hemispherical lens that now, can be provided with phosphor powder layer or be made by the material that is mixed with fluorescent material in the surrounding of described LED chip.
Preferably, described fluorescent material is one or more the mixture in yellow fluorescent powder, red fluorescence powder and green emitting phosphor.
In another embodiment, described LED chip is the positive cartridge chip of blue-ray LED, and it is electrically connected to described line layer by Bonding.
According to the present invention, described protective layer is metal level, preferably by copper, aluminium, gold, silver, is made.Especially, the thickness of described protective layer is equal to or greater than the thickness of described line layer.
In one embodiment, be also provided with insulating barrier between described flexible base, board and protective layer, described insulating barrier is preferably made with PI, PET or epoxy resin.
In one embodiment, described LED package assembling also comprises the adhesive layer of the side away from described flexible base, board that is arranged on described protective layer, and it is for being connected with heat sink.
LED package assembling according to the present invention has flexible substrate, has expanded its range of application.In addition, the substrate of this LED package assembling has simple structure, makes formed thermal resistance lower.In addition, the preparation of this LED package assembling is simple, and production cost is low.
Embodiment
Below by take can send white light LED package assembling as example and describe by reference to the accompanying drawings the present invention.
Fig. 1 has shown the white-light LED encapsulation assembly according to the first embodiment of the present invention.As shown in Figure 1, this white-light LED encapsulation assembly 10 comprises flexible base, board 11, is formed with therein line layer 14.Flexible base, board 11 and line layer wherein 14 can be made with common used material known in the art and conventional process.
In the first side of flexible base, board 11, be coated with reflector layer 15, this first side is shown as upside in Fig. 1.In one embodiment, reflector layer 15 can be white oil layer.In the first side of flexible base, board 11, LED chip 16 is also installed.In this embodiment, LED chip 16 is white light LEDs flip-chip.Preferably, this white light LEDs flip-chip is surrounded by the lens 18 of dome-type.Yet be appreciated that this embodiment comprises the situation without lens 18 equally, this is decided according to the needs of concrete application by those skilled in the art completely.LED chip 16 comprises the electrode part 17 (for clarity sake only having shown in figure) of right quantity, and it is connected with the line layer 14 in flexible base, board 11 through being opened in the through hole in reflector layer 15.Thus, electrical connection/signal of having realized between LED chip 16 and flexible base, board 11 connects.
In the second relative side of flexible base, board 11, be provided with insulating barrier 12, this second side is shown as downside in Fig. 1.This insulating barrier 12 for example can be made by polyimides (PI), polyethylene terephthalate (PET) or epoxy resin.In the side away from flexible base, board 11 (being the downside in Fig. 1) of insulating barrier 12, be provided with protective layer 13.In this embodiment, protective layer 13 is made by macromolecular material.Preferably, protective layer 13 is made by the polymer composite that contains titanium oxide.
According to the present invention, protective layer 13 is connected with heat sink (not shown) by tack coat (not shown).Tack coat for example can be made by heat-conducting silicone grease or heat-conducting glue.Therefore, from LED chip 16, to heat sink, only there is simple a few layer material, make formed thermal resistance relatively little.This is that the thermal resistance of substrate is directly proportional to the number of plies of material because for identical material.Therefore according to the present invention, at LED chip 16, to the material layer that is only provided with lesser amt between heat sink, cause formed thermal resistance relatively little.In addition, owing to having used flexible base, board 11 at this white-light LED encapsulation assembly 10, so its encapsulating structure is comparatively simple, has reduced production cost, also can adapt to multiple different purposes.In addition, owing to directly having used White-light LED chip, can remove the series of LED encapsulation flow processs such as bonding wire, some glue, baking from, shorten the LED technological process of production, further improving product yields.In addition, because White-light LED chip has carried out sorting, so can remove the step of sorting from subsequent operation.The above-mentioned simplification that all causes manufacturing process.
This LED package assembling 10 can be prepared by following method.First, prepare flexible base, board 11, be wherein formed with line layer 14, and on flexible base, board 11, insulating barrier 12 is set, protective layer 13 and reflector layer 15.Then, White-light LED chip 16 is placed on flexible base, board 11, the electrode part 17 of White-light LED chip 16 is connected with line layer 14.If necessary, lens 18 can be set in the surrounding of LED chip 16.Be cured afterwards step, White-light LED chip 16 is fixedly connected with flexible base, board 11.After this, whole LED light source is carried out to photochromic detection.Finally, free side (away from a side of insulating barrier 12) the coating tack coat at protective layer 13, is connected with heat sink by this tack coat.
From above, can see, according to LED package assembling of the present invention, can prepare by enough simple processing steps, it has greatly reduced production cost.
Although LED chip 16 is chosen as white light LEDs flip-chip in this embodiment, yet be appreciated that LED chip 16 can be also blue-ray LED flip-chip.Now, in order to export white light, lens 18 should be made by the transparent material that is mixed with fluorescent material.In certain embodiments, fluorescent material can be one or more the mixture in yellow fluorescent powder, red fluorescence powder and green emitting phosphor.Thus, under the acting in conjunction of blue-ray LED flip-chip and the lens of the fluorescent material that contains particular color, this LED package assembling 10 can send white light.
Fig. 2 has shown white-light LED encapsulation assembly according to a second embodiment of the present invention.As shown in Figure 2, this white-light LED encapsulation assembly 20 is roughly the same with the white-light LED encapsulation assembly 10 shown in Fig. 1.Therefore,, for difference is, LED chip is wherein blue-ray LED flip-chip 26, is provided with phosphor powder layer 28 on its end face and side.The mixture of one or more that similarly, phosphor powder layer 28 can be in yellow fluorescent powder, red fluorescence powder and green emitting phosphor forms.Thus, under the acting in conjunction of the lens of the phosphor powder layer 28 of blue-ray LED flip-chip and particular color, this LED package assembling 20 can send white light.
In addition, in this embodiment, protective layer 23 is made by metal material.Preferably, protective layer 23 is made by materials such as aluminium, copper, gold, silver.Preferably, protective layer 23 is configured with the line layer with flexible base, board 11, being especially formed on wherein and has identical thickness.Yet protective layer 23 also can be configured with than flexible base, board 11, especially be formed on the larger thickness of line layer wherein.Therefore, protective layer 23 can be designed to according to different purposes to have different thickness, to meet the requirement of mechanical strength and heat dispersion.In addition, the material of protective layer 23 can design according to radiating requirements and welding demand, and very high design freedom is provided.
In addition, in this embodiment, insulating barrier 22 is not necessary, but also can omit.
Easily understand, in this embodiment, phosphor powder layer 28 also can be substituted by the lens of making such as the transparent material by being mixed with fluorescent material in the first embodiment.
In a unshowned example, the LED chip in the second embodiment can be also White-light LED chip.Now, can dispense phosphor powder layer 28.
This LED package assembling 20 can be prepared by following method.First, prepare flexible base, board 21, be wherein formed with line layer, and on flexible base, board 21, insulating barrier 22 is set, protective layer 23 and reflector layer.Then, blue-light LED chip 26 is placed on flexible base, board 21, the electrode part of blue-light LED chip 26 is connected with line layer.Be cured afterwards step, White-light LED chip 26 is fixedly connected with flexible base, board 21.Then, can or lens 28 be set at surrounding's coating phosphor powder layer 28 of LED chip 26.Take and lens 28 are set as example, be again cured after this, its temperature arranges by the curing parameter of silica gel.Afterwards, whole LED light source is carried out to photochromic detection.Finally, free side (away from a side of insulating barrier 22) the coating tack coat at protective layer 23, is connected with heat sink by this tack coat.
Fig. 3 has shown the white-light LED encapsulation assembly of a third embodiment in accordance with the invention.As shown in Figure 3, this white-light LED encapsulation assembly 30 is roughly the same with the white-light LED encapsulation assembly 10 shown in Fig. 1.Difference is, LED chip is wherein the positive cartridge chip 36 of blue-ray LED.The lens 38 that the positive cartridge chip 36 of this blue-ray LED is made by the transparent material that is mixed with fluorescent material surround.In addition, the positive cartridge chip 36 of this blue-ray LED is connected with the line layer of flexible base, board by Bonding.Bonding is that those skilled in the art is known, therefore at this, omits its detailed description.
The preparation method of above-mentioned white-light LED encapsulation assembly 30 is roughly similar to the preparation method of the white-light LED encapsulation assembly 10 in the first embodiment.Difference is, after positive cartridge chip 36 is installed on flexible base, board by blue-ray LED, also will carry out the operation of Bonding.
In a unshowned example, the LED chip in the 3rd embodiment can be also White-light LED chip.Now can dispense lens 38, or make lens 38 not comprise phosphor material powder.
Although above, in conjunction with white-light LED encapsulation assembly, the present invention is described in detail, yet easily understands, the present invention can be applied to send the LED package assembling of the light of other color equally.Now only need to, by the more known conversion of those skilled in the art, can send the light of other color, for example the gold-tinted of colour temperature 3000k.
Below by reference to the accompanying drawings and by specific embodiment the present invention is had been described in detail.Yet easily understand, these explanations can not be understood to limit scope of the present invention.Protection scope of the present invention is limited by the claims of enclosing, and any change on the claims in the present invention basis all belongs in protection scope of the present invention.