CN205282501U - Flip -chip white light LED device - Google Patents

Abstract

The utility model provides a flip -chip white light LED device, this white light LED device contains wavelength conversion layer and luminescence unit, and the luminescence unit is flip chip structure, the outside extension in order to form the protruding portion of the 2nd semiconductor layer of luminescence unit for the luminescence unit is the structure of falling T, wavelength conversion layer covers epitaxial layer substrate, a semiconductor layer and the active layer of luminescence unit totally, the upper surface of through protruding portion, and do not cover two semiconductor layer and the conventional electrode metal level of luminescence unit, set up a through -hole between a conventional electrode metal level and the semiconductor layer, this through -hole only runs through in conventional electrode metal level, the 2nd semiconductor layer and active layer for the first electrode of conventional electrode metal level and a semiconductor layer's electric connection and the second electrode of conventional electrode metal level and the 2nd semiconductor layer's electric connection. The utility model discloses the reliability is high, the light -emitting effect is good, and its manufacture craft step is simple moreover, has reduced manufacturing cost, has improved the productivity effectively.

Description

A kind of upside-down mounting white light LED part

Technical field

The utility model belongs to LED technology field, is specifically related to a kind of upside-down mounting white light LED part.

Background technology

Photodiode (LED) is response current and is excited the semiconducter device producing the light of shades of colour, have high-level efficiency, the long lifetime, not containing the advantage of the objectionable impuritiess such as Hg. Along with the fast development of LED technology, the performances such as the brightness of LED, life-span are obtained for great lifting so that the Application Areas of LED is more and more extensive, from exterior lightings such as street lamps to city's intraoral illuminations such as ornament lamps, uses all one after another or is replaced with LED as light source.

In semiconductor lighting industry, generally the structure of LED chip is divided into positive cartridge chip structure, vertical chip structure and flip-chip structure three class. Compared with other two kinds of chip structures, flip-chip structure has that heat dispersion is good, light extraction efficiency height, saturation currnet height and the advantage such as cost of manufacture is moderate, has been subjected to the great attention of Ge great LED chip producer.

For tradition upside-down mounting white light LEDs product, its packaged type is that mode that is LED wafer is bonding by crystal-bonding adhesive or eutectic welding is fixed in the bowl cup of support, gold thread is adopted to be connected with the positive pole of support by the positive pole of wafer, the negative pole of wafer is connected with the negative pole of support, then in bowl cup, fills the fluorescent glue meeting aim colour district. Based on traditional encapsulation technology, a kind of diagrammatic cross-section of traditional white light LED part structure is as shown in Figure 1, namely after being filled with bowl cup as the fluorescent glue of wavelength conversion layer, the blue light that sends in order to abundant conversion luminescence layer is also mixed to form white light, and fluorescent glue 101 covers substrate 102, first semiconductor layer 103, active layer 104 and the 2nd semiconductor layer 105 substantially. Such as, application number be 201510206231.2 patent document disclose a kind of low thermal resistance patch light-emitting diode encapsulation structure, this structure comprise the support of material at the bottom of copper, packaging plastic, at least one LED chip, one be provided for LED chip and the gold thread of support conducting, wherein, LED chip is fixed on support, gold thread is bonded on LED chip and support, and the external sheath of LED chip has packaging plastic.

But, for the encapsulation structure of this quasi-tradition, owing to the thermal expansivity of the fluorescent glue on support, LED chip, packaging plastic is different, there is certain hidden danger in package in reliability; And, for this kind of encapsulation structure, fluorescent material easily applies uneven, variable thickness and causes, and then causes the generation of the problems such as photochromic uneven, the colour cast of white light.

In addition, on existing market, LED support mostly is PPA, PCT or EMC material, and these materials all exist bigger defect in high thermal resistance, resistance to air loss etc. Although ceramics bracket has good high thermal resistance and resistance to air loss, but ceramics bracket cost is close to wafer cost, again because its sidewall can not be coated and easily leak blue light by fluorescent material, and manufacturing expense needed for ceramics bracket packaged LED is expensive, equipment investment is big, thus the LED product production capacity causing ceramics bracket is less than normal, on the high side.

In other words, the defect of traditional upside-down mounting white light LEDs product in reliability, light-out effect, manufacturing cost and price etc. becomes its bigger obstruction substituting traditional lighting product.

Practical novel content

The technical problems to be solved in the utility model overcomes the deficiencies in the prior art and provides a kind of upside-down mounting white light LED part, and this LED component reliability height, light-out effect are good, and manufacturing cost reduces, and production capacity effectively improves.

For solving above technical problem, the utility model have employed following technical scheme:

The utility model provides a kind of upside-down mounting white light LED part, this white light LED part comprises wavelength conversion layer and luminous unit, described luminous unit comprises epitaxial film substrate, successively stacking and grows the first semiconductor layer on described epitaxial film substrate, active layer, the 2nd semiconductor layer and conventional electrodes metal level, namely described luminous unit is flip-chip structure, and its key is:

Described 2nd semiconductor layer outwards extends to form protuberance so that described luminous unit is in the structure of falling T;

Described wavelength conversion layer covers described epitaxial film substrate, described first semiconductor layer, described active layer completely, until the upper surface of described protuberance, and described wavelength conversion layer does not cover described 2nd semiconductor layer and described conventional electrodes metal level, based on this kind of structure, described wavelength conversion layer can not directly contact described conventional electrodes metal level, reduce the possibility that electrode is contaminated, improve the reliability of described luminous unit further;

Between described conventional electrodes metal level and described first semiconductor layer, a through hole is set, described through hole is only through described conventional electrodes metal level, described 2nd semiconductor layer and described active layer, and described through hole is used for the first electrode of described conventional electrodes metal level and the electric connection of the electric connection of described first semiconductor layer and the 2nd electrode of described conventional electrodes metal level and described 2nd semiconductor layer.

Further, the width of described protuberance is less than or equal to 50 microns, and this width range is preferred range, both ensure that wavelength conversion layer was covered in the stability of the upper surface of described protuberance, in turn ensure that the wavelength Conversion effect of blue light in wavelength conversion layer.

Further, on described protuberance, the width of optional position is all equal, is convenient to wavelength conversion layer and more uniformly applies.

Further, the first sidewall border on described wavelength conversion layer and the 2nd sidewall border on described protuberance are put down together.

Further, the 3rd sidewall border on described epitaxial film substrate, the 4th sidewall border on described first semiconductor layer and the 5th sidewall border on described active layer form the 6th sidewall border jointly, and described 6th sidewall border is skewed, the overall appearance making described luminous unit is trapezoidal shape, this kind of structure can reduce the probability on the 2nd sidewall border that the light of first wave length passes through on described protuberance on the one hand, thus reduce the risk that blue light overflows to a certain extent, can ensure that on the other hand the light of first wave length passes through the distance of described wavelength conversion layer more even, effectively reduce aberration, make photochromic more equal one.

Further, the inclination angle scope on described 6th sidewall border is 60 �㡫80 ��, and this angle scope is preferred range, can reduce to bigger possibility the risk that blue light overflows, and ensure good photochromic homogeneity.

Further, the take up an official post described inclination angle of meaning position, described 6th sidewall border is all equal, is convenient to wavelength conversion layer and more uniformly applies.

Further, described white light LED part also includes transparent glue-line, described transparent glue-line is covered on described wavelength conversion layer, by increasing transparent glue-line on described wavelength conversion layer, the possibility that the fluorescent material greatly reduced in described wavelength conversion layer drops, thus improve the stability of manufacture craft and the reliability of described white light LED part.

Further, between described epitaxial film substrate and described first semiconductor layer, buffer layer is set, to reduce lattice mismatch.

Adopting above technical scheme, the useful effect acquired by the utility model is:

(1) the upside-down mounting white light LED part that the utility model provides, first, it is only made up of flipped light emitting unit and the wavelength conversion layer containing fluorescent material, remove support and gold thread from, reliability is far above conventional package pattern, and its wavelength conversion layer can not directly touch conventional electrodes metal level, greatly reduce the contaminated possibility of electrode, improve product reliability further; Secondly, this upside-down mounting white light LED part is directly coated on flip-chip surface due to wavelength conversion layer, it is different from the packing forms that fluorescent glue filled by conventional stent bowl cup, color can be controlled better, reducing aberration, color more equal, light-out effect is good, but also the scattering-in of photon between fluorescent material support and loss can be reduced in a large number, the brightness of improving product effectively; Moreover, the making method that this upside-down mounting white light LED part uses, removes support cost from, saves a large amount of powder glue consumption, and processing step is more simple, and manufacturing expense is low, equipment investment is few, effectively reduces manufacturing cost, it is to increase production capacity.

(2) the upside-down mounting white light LED part that the utility model provides, direct SMT encapsulation, flexible design, high performance-price ratio, saves downstream light fixture manufacturing cost greatly.

(3) the utility model provide upside-down mounting white light LED part, flip-chip can directly be mounted on heat sink on, there is better heat dispersion, longer service life, and without the restriction of support shape, size is little, light-emitting area is little, is beneficial to very much the large-scale integrated encapsulation of LED product.

Accompanying drawing explanation

Fig. 1 is a kind of diagrammatic cross-section of upside-down mounting white light LED part structure in prior art;

Fig. 2 is a kind of diagrammatic cross-section of the upside-down mounting white light LED part structure of the utility model embodiment 1;

Fig. 3 a Fig. 3 d is the making processes schematic diagram of the upside-down mounting white light LED part of the utility model embodiment 1;

Wherein,

Fig. 3 a is a kind of diagrammatic cross-section of the luminous unit of the upside-down mounting white light LED part of the utility model embodiment 1;

The array type groove that Fig. 3 b is the upside-down mounting white light LED part of the utility model embodiment 1 makes schematic diagram;

The wavelength conversion layer that Fig. 3 c is the upside-down mounting white light LED part of the utility model embodiment 1 is filled or overlapping operation schematic diagram;

Fig. 3 d is the cutting operation schematic diagram of the upside-down mounting white light LED part of the utility model embodiment 1;

Fig. 4 is a kind of diagrammatic cross-section of the upside-down mounting white light LED part structure of the utility model embodiment 2;

Fig. 5 is a kind of diagrammatic cross-section of the upside-down mounting white light LED part structure of the utility model embodiment 3.

Embodiment

Below in conjunction with the drawings and specific embodiments, the technical scheme that the utility model provides is described in further detail:

Embodiment 1

As shown in Fig. 2, Fig. 3 a, present embodiments provide a kind of upside-down mounting white light LED part, this white light LED part comprises wavelength conversion layer 201 and luminous unit 208, luminous unit 208 comprises epitaxial film substrate 202, successively stacking and grows the first semiconductor layer 203 on epitaxial film substrate 202, active layer 204, the 2nd semiconductor layer 205 and conventional electrodes metal level 206, and namely luminous unit 208 is flip-chip structure.

Especially, the 2nd semiconductor layer 205 outwards extends to be formed protuberance 2051 so that luminous unit 208 is in the structure of falling T.

Especially, wavelength conversion layer 201 covers epitaxial film substrate 202, first semiconductor layer 203, active layer 204 completely, until the upper surface 20511 of protuberance, and wavelength conversion layer 201 do not cover the 2nd semiconductor layer 205 and conventional electrodes metal level 206. By this structure, the blue light that the yellow light that the blue light that luminous unit 208 sends sends through wavelength conversion layer 201 excitated fluorescent powder containing fluorescent material itself sends with luminous unit 208, thus form white light; And, in this structure, wavelength conversion layer 201 is only formed on the upper surface 20511 of protuberance, can not directly contact conventional electrodes metal level 206, reduce the possibility that electrode is contaminated, improves the reliability of luminous unit further.

Especially, between conventional electrodes metal level 206 and the first semiconductor layer 203, a through hole 207 is set, through hole 207 only through conventional electrodes metal level 206, the 2nd semiconductor layer 205 and active layer 204, the electric connection of first electrode 2061 of through hole 207 for conventional electrodes metal level 206 and the electric connection of the first semiconductor layer 203 and the 2nd electrode 2062 of conventional electrodes metal level 206 and the 2nd semiconductor layer 205.

Wherein, the width of protuberance 2051 is less than or equal to 50 microns, this width range is preferred range, both ensure that wavelength conversion layer 201 was covered in the stability of the upper surface 20511 of protuberance, in turn ensure that the wavelength Conversion effect of blue light in wavelength conversion layer, but noting, the width range of protuberance 2051 is not limited thereto range values; In addition, on protuberance 2051, the width of optional position is all equal, is convenient to wavelength conversion layer and more uniformly applies.

Wherein, the first sidewall border 2011 on wavelength conversion layer is put down together with the 2nd sidewall border 20512 on protuberance 2051.

As a kind of preference, between epitaxial film substrate 202 and the first semiconductor layer 203, buffer layer is set, with the lattice mismatch of epitaxial film substrate 202 generation when buffer layer grows for reducing the first semiconductor layer 203.

For ease of understanding the upside-down mounting white light LED part that the present embodiment provides better, the making processes of the upside-down mounting white light LED part of the present embodiment being introduced below, for reference, as shown in Fig. 3 a Fig. 3 d, making processes comprises the following steps:

S1, preparing an epitaxial film substrate 202, by controlled collapsible chip connec-tion, on epitaxial film substrate 202, stacking growth has the first semiconductor layer 203, active layer 204, the 2nd semiconductor layer 205 and conventional electrodes metal level 206 successively, forms array of light emitting cells 209;

In step sl, controlled collapsible chip connec-tion can adopt the method for metallorganic chemical vapor deposition, and metallorganic chemical vapor deposition unstripped gas used is trimethyl-gallium, trimethyl indium, trimethyl aluminium, ammonia, silane, cyclopentadienyl magnesium, two luxuriant magnesium, hydrogen or nitrogen etc.; The material of conventional electrodes metal level 206 comprises platinum (Pt), gold (Au), copper (Cu), tin (Sn), silver (Ag), aluminium (Al), or their alloy or composition, electrode is formed by steaming plating (Evaporation), deposition (Deposition), plating (ElectricalPlating) or chemical plating (ChemicalPlating) technique usually.

S2, offer one interim substrate 211, engaged the bottom surface of array of light emitting cells 209 by viscosity glue material 210 with the upper surface of interim substrate 211 so that array of light emitting cells 209 is fixed on interim substrate 211 and compresses laminating;

The execution of step S2 is to prevent sliver, viscosity glue material 210 by two-sided being coated with high-quality High-viscosity hot melt adhesive or rubber etc. at it, then with two-sided separate-type paper compound to make, the characteristics such as biadhesive power stable, sticky is strong, charge stripping efficiency height that it has.

S3, making array type groove 212 at the end face of array of light emitting cells 209, array type groove 212 penetrates epitaxial film substrate 202, first semiconductor layer 203, active layer 204, the upper surface of through 2nd semiconductor layer 205;

S4, in array type groove 212 fill wavelength conversion layer 201, and described wavelength conversion layer 201 covers described epitaxial film substrate 202, first semiconductor layer 203 and active layer 204 completely, but wavelength conversion layer 201 can not cover the 2nd semiconductor layer 205 and conventional electrodes metal level 206, form white light LED part array 213;

Wavelength conversion layer 201 on S5, baking-curing white light LED part array 213;

In step s 5, white light LED part array 213 enters roasting together with interim substrate 211, baking-curing wavelength conversion layer 201, and its best storing temperature is 150 DEG C, and best baking time is 4 hours.

S6, the interim substrate 211 removed on white light LED part array 213, and remove viscosity glue material 210;

Step S6 performs after wavelength conversion layer 201 curing molding of the fluorescent material contained, and interim substrate 211 can repeatedly reuse, and effectively saves manufacturing cost.

S7, mid-way along array type groove 212 are cut, and isolate sidewall also by the single white light LED part that wavelength conversion layer 201 is coated, and the sidewall of the 2nd semiconductor layer 205 is completely exposed;

S8, test, sorting, the single white light LED part of packaging.

Wherein, in step s3, the making method of array type groove 212 comprises cut mechanically, laser cutting, wet etching or dry etching; In step s 4 which, the filling of wavelength conversion layer 201 or covering method comprise flourescent sheet MOLDING, spray, revolve and be coated with or sputtering fluorescent material; In step s 6, the removing method of interim substrate 211 comprises thermal separation method, water soluble method or laser separation process, and the material of middle viscosity glue material 210 is depended in the selection of the removing method of interim substrate 211.

Wherein, in step s3, the width of array type groove 212 is 100 microns, and this width value can ensure to cut out the 2nd semiconductor layer protuberance 2051 that width is less than or equals 50 microns.

Wherein, interim substrate 211 is aluminium oxide ceramic substrate or metal substrate, it is possible to effectively ensure that interim substrate has certain degree of hardness and rigidity.

Embodiment 2

A kind of upside-down mounting white light LED part that the present embodiment provides, as shown in Figure 4, only it is with embodiment 1 difference structurally: the 6th sidewall border 2081 that the 4th sidewall border 2031 on the 3rd sidewall border 2021, first semiconductor layer 203 on epitaxial film substrate 202 and the 5th sidewall border 2041 on active layer 204 are formed jointly is in skewed so that the overall appearance of luminous unit 208 is trapezoidal shape.

Owing to the 2nd sidewall border 20512 of protuberance 2051 is not covered by wavelength conversion layer 201, there is the risk of the blue light of certain leakage. After the 6th sidewall border 2081 is skewed, the light with first wave length is through reflective layer reflects and when passing through wavelength conversion layer 201, the light that can reduce first wave length passes through the probability of the sidewall 20512 of protuberance 2051, thus reduces the risk that blue light overflows to a certain extent; Further, the distance that this structure makes the light of first wave length pass through wavelength conversion layer 201 is more even, thus reduces aberration so that photochromic more equal one.

Preferably, the scope at inclination angle 302 and 303 is 60 �㡫80 ��, and this value range can reduce to bigger possibility the risk that blue light overflows, and ensures good photochromic homogeneity.

In addition, on the 6th sidewall border 2081, the inclination angle 301 of optional position is all equal, so that wavelength conversion layer 201 more uniformly applies.

For a kind of upside-down mounting white light LED part that the present embodiment provides, its making method is identical with embodiment 1, but its inclination angle can depending on different situations.

Embodiment 3

A kind of upside-down mounting white light LED part that the present embodiment provides, as shown in Figure 5, and embodiment 2 difference structurally is only: this white light LED part also includes transparent glue-line 401, and transparent glue-line 401 is covered on wavelength conversion layer 201.

Identical with embodiment 2, also in skewed, there is inclination angle 402 in the 6th sidewall border 2081 in the present embodiment.

Wherein, the thickness range of wavelength conversion layer 201 is 5��15 microns so that the thickness of wavelength conversion layer 201 is in thinner and preferably in scope, to ensure that this white light LED part has good photochromic homogeneity. But the thickness of wavelength conversion layer 201 is not limited thereto in thickness range, concrete thickness is determined according to the needs of actual product.

A kind of upside-down mounting white light LED part that the present embodiment provides, is with the difference of embodiment 1, embodiment 2 in making method,

(1) in step s 4 which, being also filled with transparent glue-line in array type groove 212, transparent glue-line 401 is covered on wavelength conversion layer 201, step S4 be divided into following 3 step by step:

1st substep: fill wavelength conversion layer 201 in array type groove 212, and wavelength conversion layer 201 covers epitaxial film substrate 202, first semiconductor layer 203 and active layer 204 completely, but wavelength conversion layer 201 can not cover the 2nd semiconductor layer 205 and conventional electrodes metal level 206;

Wherein, wavelength conversion layer 201 only comprises fluorescent material, and the filling of wavelength conversion layer 201 or covering method can for spraying, revolve painting and sputtering etc.

2nd substep: Procuring wavelength conversion layer 201;

In this step, by Procuring operation so that wavelength conversion layer 201 is in solid-state, to prevent it have impact on the homogeneity of wavelength Conversion layer thickness in the random flowing in array of light emitting cells 209 surface, further, it is more conducive to transparent glue-line in solid-state wavelength conversion layer apply on its surface.

3rd substep: make transparent glue-line 401 on wavelength conversion layer 201;

The possibility that the fluorescent material that transparent glue-line 401 can reduce in wavelength conversion layer 201 drops, thus improve the stability of making technology and the reliability of this white light LED part. Transparent glue-line 401 can be made by revolving painting, printing or shaping process for filling colloid, the material of transparent glue-line 401 can be transparent and flexible material, such as epoxy resin (EPOXY), silicon rubber (SILICONERUBBER), silicone resin (SILICONERESIN), Silica hydrogel (SILICONEGEL), elasticity PU (ELASTICPU), porous PU (POROUSPU) or propylene vinegar rubber (ACRYLICRUBBER) etc.

In step s 5, (2) wavelength conversion layer 201 carries out baking-curing together with transparent glue-line 401.

In the step s 7, (3) sidewall of single white light LED part is coated by wavelength conversion layer 201 and transparent glue-line 401.

Finally it is noted that these are only preferred embodiment of the present utility model; it is not limited to the utility model; although the utility model being described in detail with reference to embodiment; for a person skilled in the art; technical scheme described in foregoing embodiments still can be modified by it; or wherein part technology feature is carried out equivalent replacement; but it is all within spirit of the present utility model and principle; any amendment of being done, equivalent replacement, improvement etc., all should be included within protection domain of the present utility model.

Claims (9)

1. a upside-down mounting white light LED part, this white light LED part comprises wavelength conversion layer (201) and luminous unit (208), described luminous unit (208) comprises epitaxial film substrate (202), successively stacking and grows the first semiconductor layer (203) on described epitaxial film substrate (202), active layer (204), the 2nd semiconductor layer (205) and conventional electrodes metal level (206), it is characterised in that:

Described 2nd semiconductor layer (205) outwards extends to form protuberance (2051) so that described luminous unit (208) is in the structure of falling T;

Described wavelength conversion layer (201) covers described epitaxial film substrate (202), described first semiconductor layer (203), described active layer (204) completely, until the upper surface (20511) of described protuberance (2051), and described wavelength conversion layer (201) do not cover described 2nd semiconductor layer (205) and described conventional electrodes metal level (206);

Between described conventional electrodes metal level (206) and described first semiconductor layer (203), a through hole (207) is set, described through hole (207) is only through described conventional electrodes metal level (206), described 2nd semiconductor layer (205) and described active layer (204), the electric connection of first electrode (2061) of described through hole (207) for described conventional electrodes metal level (206) and described first semiconductor layer (203), and the electric connection of the 2nd electrode (2062) of described conventional electrodes metal level (206) and described 2nd semiconductor layer (205).

2. upside-down mounting white light LED part according to claim 1, it is characterised in that: the width of described protuberance (2051) is less than or equal to 50 microns.

3. upside-down mounting white light LED part according to claim 1 and 2, it is characterised in that: the width of the upper optional position of described protuberance (2051) is all equal.

4. upside-down mounting white light LED part according to claim 1, it is characterised in that: the first sidewall border (2011) on described wavelength conversion layer (201) is put down together with the 2nd sidewall border (20512) on described protuberance (2051).

5. upside-down mounting white light LED part according to claim 1, it is characterized in that: the 5th sidewall border (2041) on the 3rd sidewall border (2021) on described epitaxial film substrate (202), the 4th sidewall border (2031) on described first semiconductor layer (203) and described active layer (204) forms the 6th sidewall border (2081) jointly, and described 6th sidewall border (2081) is in skewed.

6. upside-down mounting white light LED part according to claim 5, it is characterised in that: the inclination angle scope on described 6th sidewall border (2081) is 60 �㡫80 ��.

7. upside-down mounting white light LED part according to claim 6, it is characterised in that: the described inclination angle of upper optional position, described 6th sidewall border (2081) is all equal.

8. upside-down mounting white light LED part according to claim 7, it is characterized in that: described white light LED part also includes transparent glue-line (401), described transparent glue-line (401) is covered on described wavelength conversion layer (201).

9. upside-down mounting white light LED part according to claim 1, it is characterised in that: between described epitaxial film substrate (202) and described first semiconductor layer (203), buffer layer is set.