CN102299226B - LED (light emitting diode) with vertical structure and manufacturing method thereof - Google Patents
LED (light emitting diode) with vertical structure and manufacturing method thereof Download PDFInfo
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- CN102299226B CN102299226B CN201010209367.6A CN201010209367A CN102299226B CN 102299226 B CN102299226 B CN 102299226B CN 201010209367 A CN201010209367 A CN 201010209367A CN 102299226 B CN102299226 B CN 102299226B
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- 238000004519 manufacturing process Methods 0.000 title claims abstract description 14
- 239000004065 semiconductor Substances 0.000 claims abstract description 77
- 239000000758 substrate Substances 0.000 claims abstract description 53
- 238000000034 method Methods 0.000 claims abstract description 39
- 238000000227 grinding Methods 0.000 claims abstract description 5
- 239000000463 material Substances 0.000 claims description 9
- 238000005229 chemical vapour deposition Methods 0.000 claims description 7
- 239000000919 ceramic Substances 0.000 claims description 3
- 239000011521 glass Substances 0.000 claims description 3
- 238000001451 molecular beam epitaxy Methods 0.000 claims description 3
- 239000000853 adhesive Substances 0.000 claims description 2
- 230000001070 adhesive effect Effects 0.000 claims description 2
- 229910052751 metal Inorganic materials 0.000 claims description 2
- 239000002184 metal Substances 0.000 claims description 2
- 238000002360 preparation method Methods 0.000 claims 1
- 239000012634 fragment Substances 0.000 abstract description 2
- 239000010408 film Substances 0.000 description 29
- 229910002601 GaN Inorganic materials 0.000 description 15
- 229910052594 sapphire Inorganic materials 0.000 description 8
- 239000010980 sapphire Substances 0.000 description 8
- 238000005516 engineering process Methods 0.000 description 6
- 238000000605 extraction Methods 0.000 description 5
- 238000013517 stratification Methods 0.000 description 5
- JMASRVWKEDWRBT-UHFFFAOYSA-N Gallium nitride Chemical compound [Ga]#N JMASRVWKEDWRBT-UHFFFAOYSA-N 0.000 description 4
- 238000009792 diffusion process Methods 0.000 description 4
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- CHPZKNULDCNCBW-UHFFFAOYSA-N gallium nitrate Chemical compound [Ga+3].[O-][N+]([O-])=O.[O-][N+]([O-])=O.[O-][N+]([O-])=O CHPZKNULDCNCBW-UHFFFAOYSA-N 0.000 description 2
- 229910001316 Ag alloy Inorganic materials 0.000 description 1
- 239000000956 alloy Substances 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- 239000004411 aluminium Substances 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
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- 229940044658 gallium nitrate Drugs 0.000 description 1
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical group [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 1
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Abstract
The invention discloses an LED (light emitting diode) with a vertical structure and a manufacturing method thereof. The LED structure comprises an N electrode, a semiconductor thick film arranged on the N electrode, a semiconductor epitaxial layer arranged on the semiconductor thick film and a P electrode arranged on the semiconductor epitaxial layer. The structure uses a P-type semiconductor layer as a light emitting surface, the light-emitting area can be increased and the light-emitting efficiency can be improved compared with that of an electrode structure at the same side. The manufacturing method of the LED with the vertical structure utilizes a temporary bonding process and a thick film process and uses a temporary substrate to support grinding and remove the growing substrate; compared with the usual vertical structure process, a laser lift-off process can be used to reduce the damage to GaN and the fragment phenomenon caused by the problems such as bonding process unevenness and the like, thus the rate of qualified products of the chip with the vertical structure can be improved.
Description
Technical field
The present invention relates to a kind of structure and manufacture method thereof of light-emitting diode, refer in particular to a kind of light-emitting diode and manufacture method thereof of vertical stratification.
Background technology
Light-emitting diode has that volume is little, efficiency is high and the advantage such as the life-span is long, in fields such as traffic indication, outdoor panchromatic demonstrations, has a wide range of applications.Especially utilize large-power light-emitting diodes may realize semiconductor solid lighting, cause mankind's revolution of history of throwing light on, thereby become gradually the study hotspot of current person in electronics.The light extraction efficiency of LED refers to the ratio that shines the outer photon that can be produced by electron-hole recombinations for the active area of the photon utilizing and epitaxial wafer of device.In traditional LED device, because substrate absorbs, electrode stops, the existence of the factors such as total reflection of exiting surface, light extraction efficiency is conventionally less than 10%, and most photons are limited in device inside cannot outgoing and be transformed into heat, becomes the undesirable element that affects device reliability.For improving light extraction efficiency, make the photon producing in device body be transmitted into more external, and improve device inside thermal characteristics, through years of researches and practice, people have proposed the method that multiple light extraction efficiency improves, such as CURRENT DISTRIBUTION and current-dispersing structure, chip form geometrization structure, surface micro-structure etc.
Conventionally the chip structure of LED be on the substrates such as sapphire successively extension the structure of n type semiconductor layer, active layer, p type semiconductor layer.In addition, on p type semiconductor layer, dispose P electrode, on n type semiconductor layer, dispose N electrode.Final chip can be positive assembling structure, inverted structure, vertical stratification etc.Wherein, as shown in Figure 1, two electrodes of vertical structure LED are respectively in the both sides up and down of active layer for traditional vertical stratification, and electric current almost whole vertical currents is crossed gallium nitride-based epitaxial layer, there is no the electric current of lateral flow.Therefore, resistance reduces, and does not have electric current congested, and CURRENT DISTRIBUTION is even, makes full use of the material of luminescent layer, and the heat that electric current produces reduces, lower voltage, and antistatic effect improves.Its traditional manufacturing process comprises the steps: (to comprise successively n type semiconductor layer, active layer, p type semiconductor layer at Grown on Sapphire Substrates one intermediary layer and gallium nitride-based epitaxial layer, Deng), bonding one conductive support substrate on gallium nitrate based p type semiconductor layer, the stacked P electrode of another side of this conductive support substrate.Utilize Ear Mucosa Treated by He Ne Laser Irradiation on intermediary layer, gallium nitride decomposes, and Sapphire Substrate is separated with gallium nitride-based epitaxial layer, and laser lift-off, then manufactures the making that N electrode completes chip structure.Yet the technique of peeling off Sapphire Substrate is more complicated often, be unfavorable for producing the raising of yields.
How breaking through prior art further improves light emission rate, improves chip yields and remain those skilled in the art's technical task urgently to be resolved hurrily.
Summary of the invention
The technical problem to be solved in the present invention is to provide a kind of novel light emitting diode with vertical structure and manufacture method thereof.
In order to solve the problems of the technologies described above, the present invention adopts following technical scheme:
A light emitting diode with vertical structure, comprising: N electrode, be positioned at semiconductor thick film on described N electrode, be positioned at semiconductor epitaxial layers on described semiconductor thick film, be positioned at the P electrode on described semiconductor epitaxial layers;
Described semiconductor epitaxial layers at least comprises n type semiconductor layer, is positioned at the active layer on described n type semiconductor layer, and is positioned at the p type semiconductor layer on described active layer;
Described semiconductor thick film is the GaN base semiconductor material being obtained by growth substrates epitaxial growth, and its thickness is 70-150 μ m.
Wherein, between described P electrode and described semiconductor epitaxial layers, be also provided with current-diffusion layer.Between described N electrode and described semiconductor thick film, be provided with N-type reflector.
A manufacture method for above-mentioned light emitting diode with vertical structure, comprises the steps:
Step 1, the layer of semiconductor of growing in growth substrates thick film, growing semiconductor epitaxial loayer on described semiconductor thick film again, this semiconductor epitaxial layers at least comprises n type semiconductor layer, is positioned at the active layer on described n type semiconductor layer, and is positioned at the p type semiconductor layer on described active layer;
Step 2, on described p type semiconductor layer, make P electrode;
Step 3, utilize interim bonding techniques interim substrate of bonding on described P electrode;
Step 4, grinding are removed growth substrates until expose described semiconductor thick film;
Step 5, the described semiconductor thick film surface making N electrode exposing;
Step 6, utilization are separated bonding techniques and are removed the interim substrate on P electrode.
Wherein, the thickness of described semiconductor thick film is 70-150 μ m, and material can be GaN.Described interim substrate has high temperature resistant, the characteristic of acid-alkali-corrosive-resisting, and preferentially selecting substrate is Si substrate, ceramic substrate or glass substrate etc.
In step 1, utilize metal organic chemical vapor deposition, molecular beam epitaxy or the plasma chemical vapor deposition described semiconductor thick film of growing.In step 2, can first on P type GaN layer, prepare current-diffusion layer, then make P electrode.In step 5, can first on the semiconductor thick film surface of exposing, prepare N-type reflector, then make N electrode, making p type semiconductor layer is exiting surface.Separate after bonding, also need to clean the residual booty at bonding face place.
As preferred version of the present invention, can before step 1 growing semiconductor thick film, first to growth substrates, carry out scribing, be divided into a plurality of unit; Or before step 2 is made P electrode, first carry out scribing, draw to growth substrates, semiconductor epitaxial layers and semiconductor thick film are divided into independently unit.
Beneficial effect of the present invention is:
The present invention be take p type semiconductor layer as exiting surface, compare normal homonymy structure electrode, increased lighting area, improved light extraction efficiency, compare with common vertical stratification technique, reduce the damage of laser lift-off to GaN, reduced in laser lift-off due to the fragment phenomenon that problem causes such as bonding technology is inhomogeneous simultaneously, improved the yields of thin-film LED; Technology is just being drawn in utilization of the present invention, first Sapphire Substrate is divided into separate unit, (size of described separate unit is identical with the size of final chip) does thick film growth and epitaxial growth again, reduce the stress in thin film in thick film growth and epitaxial process, reduced thick film in epitaxial process or epitaxial loayer because the reason of stress causes sliver or warpage; This is just drawing technique can also can be before making P electrode before growth thick film, and preferential can be before growth thick film or before grown epitaxial layer; The present invention utilizes interim bonding techniques, before grind removing Sapphire Substrate, first by chip bonding on interim substrate, in process of lapping, reduced the whole stress in thin film causing due to thick film growth larger, in process of lapping, the easy warpage of chip or sliver phenomenon.
Accompanying drawing explanation
Fig. 1 is the schematic diagram of light emitting diode with vertical structure traditional in background technology.
Fig. 2-7th, each step schematic diagram of the inventive method, wherein Fig. 7 is the schematic diagram of light emitting diode with vertical structure of the present invention.
Embodiment
Please refer to Fig. 2 to Fig. 7, illustrate the implementation process of light emitting diode with vertical structure manufacture method of the present invention:
Step 1, the layer of semiconductor of growing in growth substrates thick film, growing semiconductor epitaxial loayer on described semiconductor thick film again, this semiconductor epitaxial layers at least comprises n type semiconductor layer, is positioned at the active layer on described n type semiconductor layer, and be positioned at the p type semiconductor layer on described active layer, as shown in Figure 2.
Wherein, can adopt method growing semiconductor thick film and the semiconductor epitaxial layers such as chemical vapour deposition technique (CVD), plasma chemical vapor deposition (PECVD), metallic compound vapour deposition process (MOCVD), molecular beam epitaxy (MBE).Described growth substrates is Si substrate, SiC substrate or Sapphire Substrate, preferred Sapphire Substrate in the present embodiment.The thick semiconductor film thickness of controlling growth is 70-150 μ m, the thickness requirement that meets at present normal chip, its material can be GaN, described n type semiconductor layer is preferably N-type GaN layer, p type semiconductor layer is preferably P type GaN layer, and active layer is preferably GaN based quantum well layer.
Step 2, on described p type semiconductor layer, make P electrode, as shown in Figure 3.Now, can first on P type GaN layer, prepare current-diffusion layer, then make P electrode.The material of current-diffusion layer is ITO material, can play the effect of current spread.
Step 3, utilize interim bonding techniques interim substrate of bonding on described P electrode, as shown in Figure 4.Wherein, described interim substrate is Si substrate, ceramic substrate or glass substrate etc., plays a supportive role, and the present embodiment is chosen Si substrate.Conventionally interim bonding Technology Need applies intermediate materials as adhesive etc. between interim substrate and device wafers, then bonding in vacuum environment; After interim bonding, can carry out back side processing (attenuate, etching, metallization etc.) to this wafer lamination, finally by separating bonding techniques, the device wafers after processing be stripped down from interim substrate.
Step 4, grinding are removed growth substrates until expose described semiconductor thick film, as shown in Figure 5.
Step 5, on the described semiconductor thick film surface of exposing, make N electrode, as shown in Figure 6.Now, can first on the semiconductor thick film surface of exposing, prepare N-type reflector, then make N electrode, making P type GaN face is exiting surface.N-type reflector is Ag or Al or aluminium silver alloy, and electrode is gold or alloy material.
Step 6, utilization are separated bonding techniques and are removed the interim substrate on P electrode, as shown in Figure 7.Separate after bonding, also need to clean the residual booty at bonding face place.The structure finally obtaining, through subsequent techniques such as cutting, encapsulation, can obtain the light-emitting diode chip for backlight unit of the vertical stratification that light emission rate is higher.
For large-sized growth substrates, in order to prevent because growth is during thick film, the stress of epitaxial loayer is excessive, cause in grinding technics, the phenomenon of the easy sliver of chip, can be before step 1 growing semiconductor thick film, first growth substrates is carried out to laser scribing, be divided into a plurality of chip units, owing to having formed road plan in growth substrates, the semi-conducting materials such as GaN cannot be grown in road plan, so without etching, can spontaneous each monomer chip structure that is extended upward the dark road plan separation of formation by this road plan that grows into of extension.Or can before step 2 is made P electrode, first carry out laser scribing, draw to growth substrates, semiconductor epitaxial layers and semiconductor thick film are divided into independently unit, reduce the stress of rete.
Other process conditions that relate in the present invention are common process condition, belong to the familiar category of those skilled in the art, do not repeat them here.Above-described embodiment is the unrestricted technical scheme of the present invention in order to explanation only.Any technical scheme that does not depart from spirit and scope of the invention all should be encompassed in the middle of patent claim of the present invention.
Claims (4)
1. a manufacture method for light emitting diode with vertical structure, is characterized in that, the method comprises the following steps:
Step 1, the layer of semiconductor of growing in growth substrates thick film, growing semiconductor epitaxial loayer on described semiconductor thick film again, this semiconductor epitaxial layers at least comprises n type semiconductor layer, is positioned at the active layer on described n type semiconductor layer, and is positioned at the p type semiconductor layer on described active layer;
Step 2, on described p type semiconductor layer, make P electrode;
Step 3, take adhesive as intermediate materials, utilize interim bonding techniques interim substrate of bonding on described P electrode; Described interim substrate is Si substrate, ceramic substrate or glass substrate;
Step 4, grinding are removed growth substrates until expose described semiconductor thick film;
Step 5, the described semiconductor thick film surface making N electrode exposing;
Step 6, utilization are separated bonding techniques and are removed the interim substrate on P electrode;
Before step 1 growing semiconductor thick film, first growth substrates is carried out to scribing, be divided into a plurality of unit.
2. according to the manufacture method of light emitting diode with vertical structure described in claim 1, it is characterized in that: the thickness of described semiconductor thick film is 70-150 μ m, and material is GaN.
3. according to the manufacture method of light emitting diode with vertical structure described in claim 1, it is characterized in that: in step 1, utilize metal organic chemical vapor deposition, molecular beam epitaxy or the plasma chemical vapor deposition described semiconductor thick film of growing.
4. according to the manufacture method of light emitting diode with vertical structure described in claim 1, it is characterized in that: in step 5, first in the preparation N-type reflector, semiconductor thick film surface of exposing, then make N electrode.
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| CN201010209367.6A CN102299226B (en) | 2010-06-24 | 2010-06-24 | LED (light emitting diode) with vertical structure and manufacturing method thereof |
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| CN102299226B true CN102299226B (en) | 2014-04-30 |
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| CN108550667B (en) * | 2018-05-04 | 2020-06-09 | 天津三安光电有限公司 | Micro light-emitting element and manufacturing method thereof |
| CN111463330B (en) * | 2019-01-18 | 2022-07-29 | 成都辰显光电有限公司 | Micro light emitting diode chip and manufacturing method and transfer method thereof |
| CN112750921B (en) * | 2019-10-30 | 2022-03-11 | 山东浪潮华光光电子股份有限公司 | Manufacturing method of gallium arsenide-based LED chip |
| CN113658859B (en) * | 2021-06-30 | 2023-09-12 | 中山大学 | Preparation method of gallium nitride power device |
| CN116207044B (en) * | 2023-04-24 | 2023-07-21 | 苏州浪潮智能科技有限公司 | Laser stripping method, equipment and medium for gallium nitride material |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1521864A (en) * | 2003-02-12 | 2004-08-18 | 财团法人工业技术研究院 | Light-emitting diode assembly and method for making same |
| CN101090096A (en) * | 2006-06-14 | 2007-12-19 | 日立电线株式会社 | Nitride semiconductor free-standing substrate and nitride semiconductor light emitting device |
| CN101552312A (en) * | 2009-05-12 | 2009-10-07 | 上海蓝光科技有限公司 | Method for fabricating light-emitting diode (LED) chip |
| CN101661988A (en) * | 2009-09-17 | 2010-03-03 | 上海蓝光科技有限公司 | Light emitting diode chip and manufacturing method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| TWI257723B (en) * | 2005-09-15 | 2006-07-01 | Epitech Technology Corp | Vertical light-emitting diode and method for manufacturing the same |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1521864A (en) * | 2003-02-12 | 2004-08-18 | 财团法人工业技术研究院 | Light-emitting diode assembly and method for making same |
| CN101090096A (en) * | 2006-06-14 | 2007-12-19 | 日立电线株式会社 | Nitride semiconductor free-standing substrate and nitride semiconductor light emitting device |
| CN101552312A (en) * | 2009-05-12 | 2009-10-07 | 上海蓝光科技有限公司 | Method for fabricating light-emitting diode (LED) chip |
| CN101661988A (en) * | 2009-09-17 | 2010-03-03 | 上海蓝光科技有限公司 | Light emitting diode chip and manufacturing method thereof |
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