Embodiment
In order to meet that, for the specification for application, the light that filtering LED is launched is sometimes necessary.In the reality of the present inventionApply in example, filter is placed in the light path that LED is launched.Can on the filter it is square into protective layer with LED'sAmbient light filter during processing and/or operation.Although light emitting semiconductor device is transmitting blue light or UV light in following exampleIII- nitrogen LED, but light emitting semiconductor device in addition to the LED of such as laser diode can be used and by such asOther materials of other III-V materials, III- phosphides, III- arsenides, II-VI material, ZnO or the material based on Si etcLight emitting semiconductor device obtained by material system.
Fig. 2 is attached to one group of LED 60 of base top view.In fig. 2, it is illustrated that base is attached to 2x2 arrays62 four LED 60.As indicated by the application, can suitably it be arranged single led or any number of LED with any60 are attached to base 62.In certain embodiments, power is supplied to LED 60 using the joint sheet 72 on base 62.
Can for example be configured to launch falling for most of light from the top surface of the LED with any LED 60 in figure belowCartridge chip device.Suitable LED 60 example is illustrated in Fig. 1, but can use any suitable LED.In order toIII- nitrogen LED are formed, as it is known in the art, growing III- nitrogen semi-conductor structures first in growth substrates.Growth substratesCan be any suitable substrate, such as sapphire, SiC, Si, GaN or compound substrate.Semiconductor structure includes being clipped in nLuminous zone or active area between type area and p-type area.Can growing n-type area, and it can include different component and mix firstMultiple layers of miscellaneous concentration, such as the plurality of layer include such as cushion or nucleating layer, and/or are designed to promote growth substratesThe preparation layer of the layer of removal etc（The preparation layer can be n-type or unintentionally adulterate）, and efficiently send out for luminous zoneThe n-type penetrating the desired particular optical of light, material or electrical properties and design or even p-type device layer.It is raw above n-type areaLong luminous zone or active area.The example of suitable luminous zone includes single thick or thin luminescent layer, or including by barrier layerMultiple quantum well radiation areas of the multiple thin or thick luminescent layer separated.It is then possible to p-type is grown above luminous zoneArea.Similar to n-type area, p-type area can include multiple layers of different component, thickness and doping concentration, and the plurality of layer has including non-The layer or n-layer of meaning doping.The gross thickness of all semi-conducting materials is less than 10 μm and one in certain embodiments in deviceIt is less than 6 μm in a little embodiments.In certain embodiments, p-type area is grown first, followed by active area and n-type area.
Metal p contacts are formed in p-type area.If most of be just exported by the surface relative with p contacts is partly ledBody structure（Such as in flip chip devices）, then p contacts can be reflexive.Half can be made by being operated by standard lithographicConductor structure is patterned and the semiconductor structure is etched to remove a part for the whole thickness of p-type area and luminous zoneA part for whole thickness is to form the table top on the surface for exposing the n-type area for being formed on metal n contacts, to form upside-down mounting corePiece device.Table top and p contacts and n contacts can be formed in any suitable manner.Form table top and p contacts and n contactsIt is well known to those skilled in the art.
Fig. 3 is attached to the section view of four LED 60 of base 62 simplification.LED can be 2x2 arrays, linear battle arrayRow or any other part suitably arranged.It can be installed on single-base 62 more more or less than illustrated fourLED.P contacts and n contacts, gold stud bump can be passed through（gold stud bump）Or any other suitable connection mechanism willLED 60 is connected to base 62.Can be by the underfill of such as epoxy resin, silicones or any other suitable material etcIn any space below material injection LED, between LED 60 and base 62.Such as removing the place later of growth substrates etcDuring managing step, base 62 and underfill can mechanically support semiconductor structure.Any suitable base can be used.CloseThe example of suitable base includes the insulation of the conductive via with being used to be formed to the electrical connection of semiconductor structure or semi-insulating chip（Such as silicon wafer or ceramic wafers）, metal structure or any other suitable base.In certain embodiments, in semiconductor junctionThick metal bond pads are formed on structure to support semiconductor structure during the processing of growth substrates etc is such as removed.Can beGrowth substrates partly or are generally removed before or after LED 60 is attached into base 62, or growth substrates can leaveA part as device.The semiconductor structure exposed by removing growth substrates can be roughened, pattern or linePhysics and chemistry is to improve light extraction.
During with the process phase independence illustrated in Fig. 3, Wavelength transformational structure is prepared, as illustrated in Fig. 4,5 and 6's.
In Fig. 4, light filter layer 102 is formed on Wavelength transformational structure 100.Wavelength transformational structure 100 is pre-productionWavelength converting member（The self-supporting being formed separately with Fig. 3 LED 60 and base 62（self-supporting）RippleLong translation building block）, it includes the light absorbed by LED transmittings and launches one or more wavelength convert materials of the light of different wave lengthMaterial.One example of suitable Wavelength transformational structure 100 is self-supporting wavelength converting ceramic plate.Wavelength converting ceramic can be exampleSuch as it is sintered into the powder phosphor of self-supporting slab.Except phosphor itself, the plate, which does not include typically, combines agent material.SuitablyPlate can for example be at least 50 μ m-thicks in certain embodiments, in certain embodiments no more than 500 μ m-thicks, in some embodimentsIn at least 100 μ m-thicks, and be no more than 300 μ m-thicks in certain embodiments.Another example of suitable Wavelength transformational structure 100It is to be placed in transparent material to form the powder material for transformation of wave length of self supporting structure.The example of suitable transparent material includesSilicones, glass and epoxy resin.
In Wavelength transformational structure 100（It is a variety of）Material for transformation of wave length can be conventional phosphor, organic phosphor, amountSub- point, organic semiconductor, II-VI or III-V semiconductors, II-VI or III-V semiconductor-quantum-points or nanocrystal, dyestuff, gatherCompound or luminous material.Any suitable powder phosphor can be used, including but not limited to based on garnet phosphor,Such as,（ItsInAnd）、、、、And based on nitrogenPhosphor（Such asWith）.
Wavelength transformational structure 100 can include single material for transformation of wave length, material for transformation of wave length mixing or be formed as singleOnly layer rather than the multiple material for transformation of wave length mixed.The material for transformation of wave length that can will launch the light of different colours is pacifiedPut in the individual region of Wavelength transformational structure 100 or be blended together.
Light filter layer 102 can be deposited on the side of Wavelength transformational structure 100.In certain embodiments, filterLayer 102 is dichroic filter.Dichroic filter can be by such asEtc it is alternate（alternating）The thin layer of material and any other suitable material is formed.The thickness of filter layer 102 can be in some realitiesIt is at least 10nm to apply in example, in certain embodiments no more than 5 μ m-thicks, at least 1 μ m-thick, and at some in certain embodimentsIt is no more than 2 μ m-thicks in embodiment.Total number of plies can be at least 2 layers in certain embodiments in light filter layer 102, in some realitiesApply no more than 50 layers, in certain embodiments at least 10 layers in example, and be no more than 30 layers in certain embodiments.Each layer canTo be identical thickness or the layer of different-thickness can be used.Can by being sputtered including megatron, DC sputtering, etc. fromDichroic filter layer 102 is deposited on wavelength and turned by any appropriate technology of son vapour deposition, chemical vapor deposition and evaporationChange in structure 100.
In certain embodiments, as illustrated in figure 10, disposed between Wavelength transformational structure 100 and filter 102Smooth layer 103.The surface of Wavelength transformational structure 100 can play a role in terms of the validity of filter 102.In some implementationsIn example, if filter 102 is smoother, its performance is improved；Correspondingly, can be before filter 102 be deposited in rippleSmooth layer 103 is formed in long transformational structure 100, the smooth layer 103 is designed to be formed thereon the smooth of placement filter 102Surface.For example, wavelength converting ceramic plate can have the surface Root Mean Square between 10nm and 600 μm（RMS）Roughness.IfRMS roughness is more than such as 300 μm in some embodiments, then can be before filter 102 is formed in Wavelength transformational structure 100Top forms smooth layer 103.Smooth layer 103 can be for example, one or more Si oxides, one or more titanylsCompound, one or more silicon nitrides, one or more transition metal oxides, or one or more transitional metal nitridesThing.Smooth layer 103 can for example be at least 5nm thickness in certain embodiments, in certain embodiments no more than 500 μ m-thicks,At least 1 μ m-thick in some embodiments, and it is no more than 20 μ m-thicks in certain embodiments.
Change in the thickness of dichroic filter layer 102 may undesirably increase the " color extracted from deviceCloud "（The distribution of the color point extracted from device）Size and/or interference for being launched by material for transformation of wave length and LEDThe color target of combination spectrum.
Correspondingly, in Figure 5, it has been created above clearly in light filter layer 102（clear）Non-wavelength translation and protection layer104.The protective layer 104 can include such as silicone compounds KJR9222A/B and KRJ9226D, and other materials.OneIn a little embodiments, protective layer 104 have with the identical refractive index of light filter layer 102, to avoid the side between layer 102 and 104Loss at boundary.Can use includes such as silk-screen printing, lamination, post forming（overmolding）, casting etc. it is variousAny one in technology to form protective layer 104 above light filter layer 102.
In order to promote formation of the protective layer 104 above light filter layer 102, light filter layer 102 can be subjected to usual 2 minutesWith 30 minutes between such as oxygen plasma, UV ozone etc. processing.In order to maximize the validity of the processing, the processingThe delay between formation with protective layer 104（If any）A few houres should not be exceeded.
The thickness of protective layer 104 will be depended on for microballon explosion（micro-bead blasting）Effect reduces thickThe expected degree of control of other processes of degree, and can be from 2 to 100 μm.Assuming that conventional treatment technology, then 20-40 μM protective layer thickness typically will be enough.If silicones is used as into protection materials, the timetable solidified can be 80DEG C 1 hour, then 120 DEG C 1 hour, and be then followed by 150 DEG C 4 hours.
Another example of suitable protective layer 104 is optical clear solid film, is such as formed at the top of light filter layer 102Individual layerOr.The advantages of solid protective layer 104, is utilizing and above-described dichroicThe identical instrument of filter 102 and the number that processing step can be reduced in the case of depositing solid protective layer simultaneously.Solid-state is protectedSheath 104 can be no more than 5 μ m-thicks in certain embodiments, and it is thick to be no more than 500nm in certain embodiments.
In figure 6, for example, by sawing or any other suitable technology in area 106 to including Wavelength transformational structure100th, light filter layer 102, smooth layer 103（If there is）And the structure of protective layer 104 carries out scribing（diced）.
In the figure 7, LED 60 will be attached to by the structure of scribing, the LED 60 is attached to base 62.IllustrateOne joint sheet 110 in the left side of base 62.Each Wavelength transformational structure 100 can be connected to by LED by adhesive 10860.Any suitable adhesive can be used.One example of suitable adhesive is disposed between the tops of LED 60, in wavelengthOn the surface relative with light filter layer 102 of transformational structure 100 or silicones on both surfaces.For example, in some realitiesApply in example, adhesive 108 is dropwise distributed above each LED 60（It is distributed as a series of drop）.
In certain embodiments, material for transformation of wave length can be placed in adhesive phase 108.For example, can be by powderPhosphor is mixed with layer of silicone adhesive 108, is then placed in the tops of LED 60.
In certain embodiments, to the selection of the material for transformation of wave length in any Wavelength transformational structure in device（Such as rippleLong transformational structure 100 and adhesive phase 108, the amount of used material for transformation of wave length, filter material and thickness）It is selected toMatching by the light launched of LED 60 peak wavelength so that the non-switched pump light from LED 60 of combination and leave thisThe light wavelength conversion of structure meets predetermined specification, such as is exported for color point and lumen.
The non-conversion light launched by LED 60 is often from a part for the final spectrum of the light of the structure extraction, although simultaneouslyNeed not be such.The example of common combination includes the blue transmitting LED being combined with yellow launch wavelength transition material and green transmittingBlue transmitting LED, the UV being combined with blue transmitting and yellow launch wavelength transition material being combined with red launch wavelength transition materialLaunch LED, and launch LED with the UV that the material for transformation of wave length of blue transmitting, green transmitting and red transmitting is combined.Hair can be addedThe material for transformation of wave length of the light of other colors is penetrated with customized（tailor）From the spectrum of the light of structure transmitting.
In certain embodiments, LED 60 transmitting with blue peak wavelength light, Wavelength transformational structure 100 include absorb byThe light and green and/or gold-tinted the one or more material for transformation of wave length of transmitting that LED 60 launches, and such as absorb and come from LED60 blue light or light wavelength conversion and the material for transformation of wave length of the phosphor of transmitting feux rouges etc from Wavelength transformational structure 100It is positioned in adhesive phase 108.In certain embodiments, light of the transmittings of LED 60 with blue peak wavelength, and wavelength turnsChange the one or more that structure 100 includes absorbing by the light launched of LED 60 and launching some or all of green, yellow and feux rougesMaterial for transformation of wave length so that the material for transformation of wave length not added is positioned in adhesive phase 108.
In fig. 8, reflecting material 74 is formed above LED 60 and base 62.Reflecting material 74 fills adjacent LED 60Between area 70.Reflecting material 74 can be the transparent or reflective support matrix for being for example such as placed in such as silicones etc（matrix）In TiO2Or the reflection grain of alumina particle etc.Can be by including for example by reflection grain and branch support groupIn the mixture press-in area 70 of body or mould（molding）Any suitable technology form layer of reflective material 74.Such as Fig. 8In it is illustrated, in the area 76 for the over top that reflecting material 74 can be placed in the protective layer 104 above each device.In some embodiments, by the skill for such as promoting molding of thinner area 112 of formation reflecting material etc above joint sheet 110Art forms reflecting material 74, as illustrated in fig. 8.
In fig.9, make reflecting material 74 thinning to expose the top 78 of the protective layer 104 of the tops of LED 60 and exposed regionJoint sheet 110 in 114.When reflecting material 74 is removed, the ambient light filter layer 102 of protective layer 104 is against damages.It can lead toCross including any suitable of such as etching or such as mechanical technique of microballon explosion, wet pearl explosion, dry pearl explosion and grinding etcTechnology remove excessive reflecting material 74.For example, in dry pearl explosion, 80 μm of sodium bicarbonate particle hits instead in the gas flowPenetrate the surface of material 74.In another example, in wet pearl explosion, 180 μm of plastic grain in water slurry is guided to reflectionAt the surface of material 74.Due to different etching mechanism, when protective layer 104 is silicones dry pearl explosion be suitable,And when protective layer 104 is silicones or such asEtc solid-state material when wet pearl explosion be suitable's.
Protective layer 104 is protected and preserves the thickness of light filter layer 102, potentially avoids undesirably increasing colorThe thickness change of point cloud.Protective layer 104 should be sufficiently thick to adapt to be used to remove the removal of the technology of excessive reflecting material 74Change without allowing the break-through of light filter layer 102 to damage.Reflecting material 74 can less be resistant to and remove compared with protective layer 104Journey.The surface roughening of protective layer 104 can be promoted for removing the technology of excessive reflecting material 74, the surface roughening can be withImprove light extraction.
In certain embodiments, after excessive reflecting material 74 is eliminated, the top surface 78 of protective layer 104 is sudden and violentDew, as illustrated in Fig. 9.The reflecting material 74 between LED 60 in area 70 prevents light from LED 60 side and wavelengthThe side escape of transformational structure 100 so that pass through the big of LED 60 top, Wavelength transformational structure 100 and light filter layer 102Part light is extracted.In certain embodiments, reflecting material 74 and LED 60 side, Wavelength transformational structure, filter 102 withAnd a part for protective layer 104 directly contacts, as illustrated in Fig. 9.In certain embodiments, the top surface of reflecting material 74Flushed with the top surface 78 of protective layer 104（Planarization）.
In certain embodiments, the top surface 78 of diaphragm 68 is roughened, textures or patterned is carried with improving lightTake.Can be by removing the same process of excessive reflecting material 74 or in one or more individually processing steps on surfaceIt is upper to form roughening, veining or patterning.
Although the present invention is described in detail, skilled artisans will appreciate that, the disclosure is given, can be withThe modification of the present invention is made in the case of the spirit without departing from inventive concepts described herein.Therefore, it is not intended that this is sent outBright scope is restricted to illustrated and description specific embodiment.