CN100483755C - High power LED flip-chip and its manufacturing method - Google Patents
High power LED flip-chip and its manufacturing method Download PDFInfo
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- CN100483755C CN100483755C CNB2005101104742A CN200510110474A CN100483755C CN 100483755 C CN100483755 C CN 100483755C CN B2005101104742 A CNB2005101104742 A CN B2005101104742A CN 200510110474 A CN200510110474 A CN 200510110474A CN 100483755 C CN100483755 C CN 100483755C
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- 239000002184 metal Substances 0.000 claims abstract description 35
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- 229910052710 silicon Inorganic materials 0.000 claims abstract description 32
- 239000010703 silicon Substances 0.000 claims abstract description 32
- 229910010038 TiAl Inorganic materials 0.000 claims abstract description 10
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 claims abstract 3
- 229910052737 gold Inorganic materials 0.000 claims description 50
- 229910052782 aluminium Inorganic materials 0.000 claims description 33
- 229910052719 titanium Inorganic materials 0.000 claims description 32
- 229910052709 silver Inorganic materials 0.000 claims description 24
- 229910052594 sapphire Inorganic materials 0.000 claims description 20
- 239000010980 sapphire Substances 0.000 claims description 20
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- 238000005566 electron beam evaporation Methods 0.000 claims description 7
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Abstract
The invention relates to a high-power LED face-down chip, formed by P-N electrode extending sheet and silicon substrate with reflective layer, wherein the P-N electrodes have inactivate layer between; the characteristic semi-conductive silicon substrate has electric insulated layer above; the metal reflective layer is above the insulated layer; the P-N electrode extending sheet and the silicon substrate with reflective layer are face-down welded to form high-power LED face-down chip. And its production comprises that: on silicon substrate, using PECVD to deposit one layer of P-N electrode electric insulated layer as SiO<SUB>2</SUB> or Si<SUB>3</SUB>N<SUB>4</SUB> insulated layer at 50-100nm thick; then using magnetic-control splash or electron beam to evaporate one layer of metal reflective layer at 200-300nm made from TiAl or TiAg. The invention can improve the lighting efficiency and radiation efficiency.
Description
Technical field
The present invention relates to the preparation method of the high power LED flip-chip of a kind of gallium nitride (GaN) semiconductor fabrication, especially relate to the technology that dispel the heat with raising light extraction efficiency and improvement in the evaporation metal reflector on silicon substrate.
Background technology
The luminous efficiency particularly low and heat-sinking capability difference of light extraction efficiency is the major technique bottleneck that great power LED faces.Traditional positive assembling structure LED light extraction efficiency mainly is subjected to the influence of following factor: 1) P-GaN semi-transparent metals contact electrode layer is 70%-80% to the optical transmission rate; 2) bonding welding point and the shield of lead-in wire on the P electrode to light; 3) GaN material relative index of refraction is higher, and light repeatedly reflects and absorbs between sapphire and semi-transparent metals electrode.Above various factors causes present LED light extraction efficiency can only reach a few percent.
Great power LED is generally operational under the 350mA electric current, heat radiation is vital to device performance, if the heat that electric current produces can not be shed timely, keep the PN junction temperature in allowed band, can't obtain stable light and export and keep normal device lifetime.For the LED of GaN base, its active layer is away from radiator, and Sapphire Substrate also is the non-conductor of heat, and heat dissipation problem is with even more serious.
At the problems referred to above, main solution comprises the following aspects at present:
1) aspect chip design, great power LED is not simply to increase light-emitting area, but by the optimised devices structure, adopts novel slotting filament, micro-structural and photonic crystal etc. to improve the internal current expansion, reduce reflection and the absorption of light, improve the extraction efficiency of light at the GaN material internal.
2) traditional LED adopts positive assembling structure, and the light that active area produces is sent by the front by the transparency conducting layer electrode, and its main shortcoming is that nearly 30% light is absorbed by the P electrode.In addition, usually apply one deck epoxy resin above during the formal dress construction packages, and the capacity of heat transmission of epoxy resin is very poor, and following substrate sapphire also is the non-conductor of heat, therefore two aspects all cause the difficult problem of heat radiation before and after, have influenced the performance parameter and the reliability of device.Adopt after the upside-down mounting, light is sent by transparent Sapphire Substrate, has avoided the absorption of electrode pair light.Heat radiation aspect, active area more approach radiator, and led chip is connected on the silicon substrate by the salient point upside-down mounting, with the transition heat carrier of silicon as chip and fin, realize low thermal resistance, have reduced the influence of thermal stress to device reliability simultaneously.Inverted structure efficiently solves the absorption and the heat dissipation problem of P electrode pair light, makes big electric current high-power LED become possibility, and than traditional positive assembling structure, inverted structure can improve 70% with the light efficiency of LED.
3) high transmission/high reflecting metal electrode system.Will take into account low ohmic contact resistance and high two aspects of light extraction efficiency in the great power LED electrode design process, the factor of restriction P electrode ohmic contact has two: the one, and the P-GaN doping content is difficult to reach the level that the hole can the tunnelling Schottky barrier; The 2nd, lack work function metal or the metal system higher than P-GaN work function.Before making device, at first P-GaN is activated, improve carrier concentration; Reduce the influence of surface state simultaneously by GaN surface treatment and wet method passivating technique, further reduce metal-semiconductor contact potential barrier.Thereby need be to multiple metal system, especially the metal system that work function is high experimentizes, and seeks preferred plan.P electrode (transparency conducting layer) generally adopts the higher thin electrodes metal system of coefficient of transparency, such as Ni/Au (nickel/gold), and PdAu (porpezite), PtAu (platinum), NiCrAu (nickel chromium triangle gold), PtMgPdAu (platinum magnesium porpezite), ITO (indium tin oxide), ZnNiAu (zinc-nickel gold) etc.For flip LED, light sends from transparent Sapphire Substrate, to the demanding light transmittance of transparency conducting layer, the metal reflective layer is required to have high reflectivity.Ag in visible wavelength range (silver) and Al (aluminium) are best speculums, to the light of 470nm-520nm wavelength, 1.2 * 10
-7Ag that m is thick (silver) and Al (aluminium) reflectivity are about 96% and 84%, are to improve the effective way of reflectivity so select Ag (silver) and Al (aluminium) Base Metal system.
Summary of the invention
Technical problem to be solved by this invention provides a kind of high power LED flip-chip, and it can effectively improve the luminous efficiency and the heat-sinking capability of high power LED flip-chip; The present invention also will provide a kind of process of making this chip for this reason.
For solving the problems of the technologies described above, high power LED flip-chip of the present invention is made up of P-N electrode epitaxial wafer and the silicon substrate that has the reflector;
P-N electrode epitaxial wafer comprises Sapphire Substrate, the N-GaN layer that on Sapphire Substrate, forms, at P-GaN layer that forms on the N-GaN layer and luminescent layer (luminescent layer is between N-GaN layer and P-GaN layer), the transparency conducting layer that helps the electric current diffusion in P-GaN laminar surface deposit formation, by P electrode and the N electrode that P-GaN layer and N-GaN layer are drawn respectively, the passivation layer of between P electrode and N electrode, growing;
The described silicon substrate that has the reflector is included in the electric isolation layer that forms on the intrinsic semiconductor silicon substrate, TiAl that forms on this electric isolation layer or TiAg metallic reflector;
Described P-N electrode epitaxial wafer carries out the upside-down mounting welding with the silicon substrate that has the reflector and forms high power LED flip-chip.
Described P electrode and N electrode adopt the metallic combination of Ti/Al/Ti/Au (titanium/aluminium/titanium/gold) or Ti/Al/Ni/Au (titanium/aluminium/nickel/gold) or Cr/Ag/Ti/Au (chromium/silver/titanium/gold) or Cr/Ag/Ni/Au (chromium/silver/nickel/gold) or Al/Ti/Au (aluminium/titanium/gold) or Al/Ni/Au (aluminium/nickel/gold) or Ag/Ti/Au (silver/titanium/gold) or Ag/Ni/Au (silver/nickel/gold), and Au (gold) is the ultra-sonic welded metal.
High power LED flip-chip process for making of the present invention comprises the steps:
At first make P-N electrode epitaxial wafer, comprise the steps: on Sapphire Substrate the N-GaN layer, luminescent layer, the P-GaN layer that form successively, adopt ICP or RIE equipment utilization chloride ion and argon ion to carry out dry etching, part P-GaN layer and luminescent layer are etched away, electrically contact thereby expose formation up to following N-GaN laminar surface; Adopt the vacuum electronic beam evaporation to form the transparency conducting layer that one deck helps the electric current diffusion on the surface of P-GaN layer; Adopt magnetron sputtering or electron beam evaporation to form the P electrode and the N electrode of drawing respectively by P-GaN layer and N-GaN layer; Between P electrode and N electrode, adopt the SiO of PECVD (plasma-reinforced chemical vapour deposition) growth one deck 70nm-120nm
2Passivation layer;
Make the silicon substrate that has the reflector then, comprise the steps: to utilize the electric isolation layer of PECVD deposit one deck P electrode and N electrode on the intrinsic semiconductor silicon substrate, this electric isolation layer is SiO
2Or Si
3N
4Insulating barrier, thickness are 50nm-100nm, are the metallic reflector of 200nm-300nm with magnetron sputtering or electron beam evaporation one layer thickness then, and this metallic reflector adopts TiAl or TiAg;
At last, the P-N electrode epitaxial wafer of making is divided into the device of 1000 μ m * 1000 μ m, the silicon substrate in the band reflector made is divided into the device of 1400 μ m * 1200 μ m, both are carried out flip chip bonding and be connected together with Die Bond (upside-down mounting welding) and Wire Bond (spun gold welding) equipment.
Because high power LED flip-chip of the present invention has increased high reflectance and the good reflector of heat conduction on silicon substrate, therefore thereby it can be led the heat of pn knot to thermal conductivity coefficient high metal Ti Al or TiAg by P electrode and N electrode and lead to the high silicon substrate of thermal conductivity coefficient, and radiating effect has improvement greatly.
Because Al and Ag metal have high reflectivity and thermal conductivity, therefore the metallic combination (silver/nickel/gold) of P electrode and N electrode employing Ti/Al/Ti/Au (titanium/aluminium/titanium/gold) or Ti/Al/Ni/Au (titanium/aluminium/nickel/gold) or Cr/Ag/Ti/Au (chromium/silver/titanium/gold) or Cr/Ag/Ni/Au (chromium/silver/nickel/gold) or Al/Ti/Au (aluminium/titanium/gold) or Al/Ni/Au (aluminium/nickel/gold) or Ag/Ti/Au (silver/titanium/gold) or Ag/Ni/Au in the present invention, Au (gold) is the ultra-sonic welded metal, and TiAl (titanium aluminium) or TiAg (titanium silver) are as the light reflective metals; The heat radiation aspect, active area more approaches radiator, adopt this structure the heat of the pn of led chip knot directly can be passed on the high metallic reflector of thermal conductivity coefficient by the high argent of thermal conductivity coefficient (thermal conductivity coefficient is 427W/mK) or aluminium (thermal conductivity coefficient is 236W/mK) and golden (thermal conductivity coefficient is 315W/mK) salient point (P electrode and N electrode), realize low thermal resistance, reduced the influence of thermal stress simultaneously device reliability.
Description of drawings
The present invention is further detailed explanation below in conjunction with accompanying drawing and embodiment:
Fig. 1 is a high power LED flip-chip structural representation of the present invention;
Fig. 2 is the brightness contrast (the chip wavelength is 465nm) of (light reflective metals titanium aluminium or titanium silver are arranged) after (unglazed reflective metals titanium aluminium or titanium silver) and the upside-down mounting before the upside-down mounting among the present invention;
Fig. 3 evaporates among the present invention on silicon substrate as the metallic reflector TiAl of light reflection and the graph of relation of TiAg reflectivity and wavelength;
Fig. 4 evaporates on P-N electrode epitaxial wafer among the present invention as the metal Ni/Au of transparency conducting layer or the graph of relation of ITO penetrance and wavelength;
Fig. 5 is as the thermal conductivity coefficient column diagram of the metal of P electrode and N electrode and reflection layer among the present invention.
Embodiment
The wave-length coverage of high power LED flip-chip of the present invention is 430nm-530nm.
As shown in Figure 1, high power LED flip-chip of the present invention is made up of P-N electrode epitaxial wafer and the silicon substrate that has the reflector.
P-N electrode epitaxial wafer comprises Sapphire Substrate, and Sapphire Substrate has the characteristic that thermal conductivity coefficient is low and insulate.The N-GaN layer that forms on Sapphire Substrate is at P-GaN layer that forms on the N-GaN layer and luminescent layer (luminescent layer is between N-GaN layer and P-GaN layer), so that electrically contact with the formation of N-GaN layer.
For flip LED, light sends from transparent Sapphire Substrate, to the demanding light transmittance of transparency conducting layer, because therefore the limited conductivity of P-GaN layer precipitate the transparency conducting layer that one deck helps the electric current diffusion at the P-GaN laminar surface in the present invention again.This transparency conducting layer generally adopts the higher thin electrodes metal system of coefficient of transparency.The present invention requires transparency conducting layer that high penetrance and good electrical conductivity are arranged in order to reduce catoptrical absorption, utilizes the vacuum electronic beam evaporation at the 450nm-550nm wave band, and adopts light transmittance good metal film Ni/Au or ITO.Thickness is Ni 2nm-10nm, Au 5nm-12nm, or ITO 200nm-300nm.
Draw P electrode and N electrode respectively by P-GaN layer and N-GaN layer.In order to solve the problem of light extraction efficiency and heat radiation to greatest extent, because Al (aluminium) and Ag (silver) metal have high reflectivity and thermal conductivity, P electrode of the present invention and N electrode (upside-down mounting weld metal or title metallic film) adopt the metallic combination (silver/nickel/gold) of Ti/Al/Ti/Au (titanium/aluminium/titanium/gold) or Ti/Al/Ni/Au (titanium/aluminium/nickel/gold) or Cr/Ag/Ti/Au (chromium/silver/titanium/gold) or Cr/Ag/Ni/Au (chromium/silver/nickel/gold) or Al/Ti/Au (aluminium/titanium/gold) or Al/Ni/Au (aluminium/nickel/gold) or Ag/Ti/Au (silver/titanium/gold) or Ag/Ni/Au, Au (gold) is the ultra-sonic welded metal, TiAl (titanium aluminium) or TiAg (titanium silver) are as the light reflective metals, and P electrode and N electrode are formed by magnetron sputtering or electron beam evaporation.
For guaranteeing the electrical stability and the antistatic effect of device, must be at chip surface, one deck passivation layer (oxidation insulating layer) of promptly growing between P electrode and the N electrode.Described passivation layer is SiO
2Oxidation insulating layer, thickness are 70nm-120nm.Not only chip surface had been carried out passivation but also strengthened light extraction efficiency.
The described silicon substrate that has the reflector is included in the electric isolation layer that forms on the intrinsic semiconductor silicon substrate, and described electric isolation layer is SiO
2Or Si
3N
4Insulating barrier, thickness are 50nm-100nm.The metallic reflector that on this electric isolation layer, forms.Described metallic reflector is TiAl or TiAg, and thickness is 200nm-300nm.
The physical dimension of described P-N electrode epitaxial wafer is 1000 μ m * 1000 μ m; The described physical dimension that has the silicon substrate in reflector is 1400 μ m * 1200 μ m.Described P-N electrode epitaxial wafer carries out the upside-down mounting welding with the silicon substrate that has the reflector and forms high power LED flip-chip.
Below in conjunction with a specific embodiment high power LED flip-chip process for making of the present invention is described:
For preparing above-mentioned high power LED flip-chip, preparation method of the present invention may further comprise the steps:
Utilization MOCVD (metal organic chemical vapor deposition) equipment epitaxial growth GaN based high-power LED structure extension sheet, substrate is sapphire (Al
3O
2).At first stroke road of etching N face step and chip size exposes the N-GaN table top, so that make N electrode and weld pad.N type table top reactive ion etching equipment RIE etching, reacting gas is Cl:Ar=10:3.
The N-GaN layer, luminescent layer, the P-GaN layer that on Sapphire Substrate, form successively, adopt ICP or RIE equipment utilization chloride ion and argon ion to carry out dry etching, part P-GaN layer and luminescent layer are etched away, electrically contact thereby expose formation up to following N-GaN laminar surface.
Evaporation one layer thickness is the transparent conductive film ITO of 200nm-300nm on the P-GaN layer afterwards, as transparency conducting layer.
The metallic combination (silver/nickel/gold) of adopting magnetron sputtering or electron beam evaporation difference evaporation to form with Ti/Al/Ti/Au (titanium/aluminium/titanium/gold) or Ti/Al/Ni/Au (titanium/aluminium/nickel/gold) or Cr/Ag/Ti/Au (chromium/silver/titanium/gold) or Cr/Ag/Ni/Au (chromium/silver/nickel/gold) or Al/Ti/Au (aluminium/titanium/gold) or Al/Ni/Au (aluminium/nickel/gold) or Ag/Ti/Au (silver/titanium/gold) or Ag/Ni/Au by P-GaN layer and N-GaN layer is P electrode, N electrode and the weld pad of metallic combination.Electrode size is 90 μ m～120 μ m (when P-N electrode epitaxial wafer is of a size of 1000 μ m * 1000 μ m).
Between P electrode and N electrode, adopt the SiO of PECVD (plasma-reinforced chemical vapour deposition) growth one deck 80nm
2Passivation layer.Use chemico-mechanical polishing (CMP) equipment that sapphire is thinned to 90 μ m～150 μ m by 350 μ m～450 μ mn then.
Utilize the electric isolation layer of PECVD (plasma-reinforced chemical vapour deposition) deposit one deck P electrode and N electrode on 2 inches intrinsic semiconductor silicon substrates, this electric isolation layer is SiO
2Or Si
3N
4Insulating barrier, thickness are 50nm-100nm, are the metallic reflector of 200nm-300nm with magnetron sputtering or electron beam evaporation one layer thickness then, and this metallic reflector adopts TiAi or TiAg.
At last, the P-N electrode epitaxial wafer of making is divided into the device of 1000 μ m * 1000 μ m, the silicon substrate in the band reflector made is divided into the device of 1400 μ m * 1200 μ m with cutting machine.The P-N electrode epitaxial wafer that performs electrode is divided into the device of 1000 μ m * 1000 μ m with laser scribing means.Both are carried out flip chip bonding and be connected together with Die Bond (upside-down mounting welding) and Wire Bond (gold thread welding) equipment.
Fig. 2 is the brightness contrast (the chip wavelength is 465nm) of (light reflective metals titanium aluminium or titanium silver are arranged) after (unglazed reflective metals titanium aluminium or titanium silver) and the upside-down mounting before the upside-down mounting of the present invention.Improved more than 50% before the brightness ratio upside-down mounting after the upside-down mounting.
Fig. 3 has disclosed the present invention and has evaporated on silicon substrate as the metallic reflector TiAl (titanium aluminium) of light reflection and the reflectivity of TiAg (titanium silver).(440nm-470nm) the former reflectivity is more than 90% in the blue light wavelength scope as seen from the figure, and the latter is up to more than 95%.
Fig. 4 has disclosed the present invention and has evaporated on P-N electrode epitaxial wafer as the metal Ni/Au of transparency conducting layer or the penetrance of ITO.(440nm-470nm) the former penetrance is 75%-80% in the blue light wavelength scope as seen from the figure, and the latter is up to more than 98%.Significantly improve the optical efficiency of getting of LED, thereby improved optical output power.
Fig. 5 is the thermal conductivity coefficient of the present invention as the metal of P electrode and N electrode and reflection layer.Yin thermal conductivity coefficient is 427W/mK as seen from the figure, and the thermal conductivity coefficient of aluminium is 236W/mK, and the thermal conductivity coefficient of gold is 315W/mK, can effectively conduct the heat of the pn knot of led chip, realizes low thermal resistance, has reduced the influence of thermal stress to device reliability simultaneously.
The invention provides a kind of high power LED flip-chip and preparation method thereof.For flip LED, light sends from transparent Sapphire Substrate, and the metal reflective layer is required that high reflectivity is arranged, and Ag and Al are best speculums in visible wavelength range.
Traditional LED adopts positive assembling structure, and its main shortcoming is that nearly 30% light is absorbed by the P electrode.Adopt after the upside-down mounting, light is sent by transparent Sapphire Substrate, has solved the absorption and the heat dissipation problem of P electrode pair light in this structure is effective.
Claims (7)
1, a kind of high power LED flip-chip is characterized in that: be made up of P-N electrode epitaxial wafer and the silicon substrate that has the reflector;
P-N electrode epitaxial wafer comprises Sapphire Substrate, the N-GaN layer that on Sapphire Substrate, forms, the luminescent layer that on the N-GaN layer, forms, the P-GaN layer that on luminescent layer, forms, the transparency conducting layer that helps the electric current diffusion in P-GaN laminar surface deposit formation, by P electrode and the N electrode that P-GaN layer and N-GaN layer are drawn respectively, the passivation layer of between P electrode and N electrode, growing;
The described silicon substrate that has the reflector is included in the electric isolation layer that forms on the intrinsic semiconductor silicon substrate, TiAl that forms on this electric isolation layer or TiAg metallic reflector;
Described P-N electrode epitaxial wafer carries out the upside-down mounting welding with the silicon substrate that has the reflector and forms high power LED flip-chip.
2, high power LED flip-chip as claimed in claim 1 is characterized in that: the metal of described transparency conducting layer is Ni/Au or ITO, and thickness is Ni 2nm-10nm, Au 5nm-12nm, or ITO 200nm-300nm.
3, high power LED flip-chip as claimed in claim 1, it is characterized in that: described P electrode and N electrode adopt the metallic combination of Ti/Al/Ti/Au or Ti/Al/Ni/Au or Cr/Ag/Ti/Au or Cr/Ag/Ni/Au or Al/Ti/Au or Al/Ni/Au or Ag/Ti/Au or Ag/Ni/Au, and Au is the ultra-sonic welded metal.
4, high power LED flip-chip as claimed in claim 1 is characterized in that: described passivation layer is SiO
2Oxidation insulating layer, thickness are 70nm-120nm.
5, high power LED flip-chip as claimed in claim 1 is characterized in that: described electric isolation layer is SiO
2Or Si
3N
4Insulating barrier, thickness are 50nm-100nm.
6, high power LED flip-chip as claimed in claim 1 is characterized in that: described metallic reflection layer thickness is 200nm-300nm.
7, a kind of high power LED flip-chip process for making as claimed in claim 1, it is characterized in that, at first make P-N electrode epitaxial wafer, comprise the steps: on Sapphire Substrate, to form successively N-GaN layer, luminescent layer, P-GaN layer, adopt ICP or RIE equipment utilization chloride ion and argon ion to carry out dry etching, part P-GaN layer and luminescent layer are etched away, electrically contact thereby expose formation up to following N-GaN laminar surface; Adopt the vacuum electronic beam evaporation to form the transparency conducting layer that one deck helps the electric current diffusion on the surface of P-GaN layer; Adopt magnetron sputtering or electron beam evaporation to form the P electrode and the N electrode of drawing respectively by P-GaN layer and N-GaN layer; Between P electrode and N electrode, adopt the SiO of PECVD growth one deck 70nm-120nm
2Passivation layer;
Make the silicon substrate that has the reflector then, comprise the steps: to utilize the electric isolation layer of PECVD deposit one deck P electrode and N electrode on the intrinsic semiconductor silicon substrate, this electric isolation layer is SiO
2Or Si
3N
4Insulating barrier, thickness are 50nm-100nm, are the metallic reflector of 200nm-300nm with magnetron sputtering or electron beam evaporation one layer thickness then, and this metallic reflector adopts TiAl or TiAg; At last, the P-N electrode epitaxial wafer of making is divided into the device of 1000 μ m * 1000 μ m, the silicon substrate in the band reflector made is divided into the device of 1400 μ m * 1200 μ m, both is carried out flip chip bonding with Die Bond and Wire Bond equipment be connected together.
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| CN100483755C true CN100483755C (en) | 2009-04-29 |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101207173B (en) * | 2007-11-30 | 2012-10-03 | 中国计量学院 | Light emitting diode with one-dimensional photon crystal |
| KR100975659B1 (en) * | 2007-12-18 | 2010-08-17 | 포항공과대학교 산학협력단 | Light emitting device and method of manufactiuring the same |
| KR20110006652A (en) * | 2008-03-25 | 2011-01-20 | 라티스 파워(지앙시) 코포레이션 | Semiconductor light-emitting device with double-sided passivation |
| CN101308838B (en) * | 2008-06-06 | 2010-06-02 | 广州南科集成电子有限公司 | Flip LED integrated chip with high break-over voltage and production method |
| CN101330080B (en) * | 2008-07-23 | 2011-09-07 | 广州南科集成电子有限公司 | High on-stage voltage right-handed LED integrated chip and manufacturing method thereof |
| CN101599522B (en) * | 2009-06-30 | 2011-05-25 | 厦门市三安光电科技有限公司 | Vertical LED adopting insulating medium barrier layer and preparation method thereof |
| CN102055053B (en) * | 2009-11-04 | 2013-09-04 | 中国科学院半导体研究所 | Bonding technology based method for manufacturing microwave transmission line |
| CN102034925B (en) * | 2010-10-28 | 2013-04-03 | 山东华光光电子有限公司 | Flat FCB (Flip Chip Bonding) GaN-based LED (Light-Emitting Diode) chip structure |
| US8574936B2 (en) * | 2010-12-29 | 2013-11-05 | Phostek, Inc. | Semiconductor light emitting device and method for manufacturing the same |
| CN103258819A (en) * | 2013-04-16 | 2013-08-21 | 佛山市领华电子实业有限公司 | LED multi-cup integrated COB package implementation method |
| CN105331940B (en) * | 2014-07-24 | 2018-08-24 | 北京北方华创微电子装备有限公司 | Method and LED component for deposited metal film on substrate |
| CN106530992A (en) * | 2016-12-28 | 2017-03-22 | 歌尔股份有限公司 | Single-color LED display screen and manufacturing process thereof |
| CN110556439A (en) * | 2018-05-31 | 2019-12-10 | 东泰高科装备科技（北京）有限公司 | flexible nitride thin-film solar cell and manufacturing method thereof |
| CN111261766A (en) * | 2020-01-21 | 2020-06-09 | 厦门乾照光电股份有限公司 | Flip film LED chip structure and preparation method thereof |
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