CN107622977A - A kind of gradual micron order Sapphire Substrate laser lift-off - Google Patents
A kind of gradual micron order Sapphire Substrate laser lift-off Download PDFInfo
- Publication number
- CN107622977A CN107622977A CN201710776207.1A CN201710776207A CN107622977A CN 107622977 A CN107622977 A CN 107622977A CN 201710776207 A CN201710776207 A CN 201710776207A CN 107622977 A CN107622977 A CN 107622977A
- Authority
- CN
- China
- Prior art keywords
- sapphire substrate
- gradual
- micron order
- laser lift
- epitaxial layer
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Landscapes
- Led Devices (AREA)
- Laser Beam Processing (AREA)
- Crystals, And After-Treatments Of Crystals (AREA)
Abstract
The invention discloses a kind of gradual micron order Sapphire Substrate laser lift-off, comprise the following steps：1) epitaxial layer needed for growth on sapphire substrate surface, and epitaxial layer is subjected to unit area division according to required；2) conductive insulating materials is filled between unit area as needed：3) epitaxial layer and transfer substrate are bonded together；4) according to counterclockwise or clockwise, using single beam or double light beam laser radiation mode, the gradual scan mode of ecto-entad straight line carries out point by point scanning, realizes Sapphire Substrate and epitaxial layer separation, and obtain good peeling effect.
Description
Technical field
The invention belongs to high-precision laser manufacture field, and in particular to a kind of gradual micron order Sapphire Substrate laser stripping
Separating process.
Background technology
Visible ray and ultraviolet band light emitting diode (Light Emitting based on III-N material systems
Diode, abbreviation LED) infrared, feux rouges, green glow, blue light, ultraviolet band High Efficiency Luminescence is done step-by-step since the 1960s,
Semiconductor illumination technique obtains fast-developing since then, and the luminous efficiency of product obtains lasting lifting, starts to substitute traditional lighting
Mode turns into market mainstream technology, and LED application markets scale has reached hundreds billion of members at this stage, therefore III-N materials have ten
Divide wide market development prospect.
LED utilizes metal organic chemical vapor deposition (MOCVD) technology generally using sapphire material as epitaxial substrate
Growth obtains epitaxial structure layer, but due to big lattice mismatch and thermal mismatching between sapphire and III-N material systems be present, and
Material itself heat conductivility and electric conductivity are poor, have had a strong impact on the making and development of great power LED.Most common plane
LED is that N-GaN layers will be etched into from P-GaN layers to expose N-type contact zone using dry etching, and N-type P-type electrode is made
In the same side of chip surface.Its electric current is from one because electronics is injected laterally into from the luminous zone for flowing through LED in the horizontal direction
Electrode sets out to another electrode, causes electric current distribution in way uneven, produces electric current congestion effect and also result in simultaneously
Non-uniform light, and heat distribution is also uneven, device quick aging failure is easily caused, so as to limit single LEDs chip
Size and device it is luminous.
Can solve the problems, such as above technical bottleneck using thin-film LED technology.Thin-film LED is by two of LED
Electrode is placed on the both sides of LED films, and electric current vertically flows through device, significantly lifts single-chip working current density, can
To prepare large scale list LEDs chip, while thoroughly solve the problems, such as sapphire insulation and poor heat radiation.Vertical structure LED core
Piece manufacture is main to use substrate transfer technology, and the raceway groove of chip chamber is first processed on epitaxial layer, then utilizes wafer bonding skill
Art will shift substrate and epitaxial wafer is bonded together, and is then utilized from sapphire side using PRK irradiation epitaxial layer
Laser lift-off technique removes Sapphire Substrate, and epitaxial layer is transferred on the good substrate of other electrical and thermal conductivity performances.Mesh
Preceding most commonly seen laser lift-off processing mode, it is along the reciprocal continuous laddering progress sapphire of horizontal or vertical direction and outer
Prolong the stripping of layer, this method technique is simple, and device hardware and programming requirement are relatively low, but laser irradiation epitaxial layer
Larger stress release and high pressure nitrogen impact will be produced simultaneously because epitaxial layer absorbs laser energy decomposition during interface, using this
The kind direction extension functional areas that laddering processing will be unstripped on its adjacent area reciprocal continuously bring serious impact to influence,
Easily cause material damage, component failure or element leakage situation are significantly aggravated, ultimately result in device process yield and from
Body reliability is greatly lowered.
The content of the invention
Object of the present invention is to provide a kind of gradual micron order Sapphire Substrate laser lift-off, its laser light
Spot realizes the stripping of Sapphire Substrate and epitaxial layer, due to laser according to the gradual point by point scanning mode of ecto-entad linear pattern
Hot spot proceeds by scanning from the periphery of processed sample, can be more effectively from high pressure nitrogen caused by stripping moment
The periphery being stripped is discharged, therefore laser lift-off moment can be greatly lowered because high pressure nitrogen is impacted to its adjacent devices
Influence, and linear pattern hot spot move mode compares round or arc line type helical ecto-entad progressive mode, to equipment movement and
The requirement that program performs complexity is greatly lowered, while square or rectangular laser hot spot are easier in fact compared to circular light spot
The complete linking of existing stripping area or hot spot are overlapping, can also peel off work by using dual-beam processing mode so as to realize to shorten
In the skill cycle, using the laser lift-off method, it can effectively lift Sapphire Substrate and peel off yield, be carried for its large-scale production
For more preferable solution.
To reach above-mentioned purpose, the present invention adopts the following technical scheme that to realize：
A kind of gradual micron order Sapphire Substrate laser lift-off, comprises the following steps：
1) growth of epitaxial layer is completed on a sapphire substrate, carrying out unit area to the epitaxial layer divides to form raceway groove,
Hard or compliant conductive insulating barrier are prepared in raceway groove between epitaxial layer unit area, first is then prepared in epi-layer surface
Layer adhesive layer；
2) in whole face, transfer substrate prepares second layer adhesive layer；
3) first layer adhesive layer and second layer adhesive layer are adhered to each other, so as to which transfer substrate and epitaxial layer are connected to
Together；
4) hot spot pattern, laser energy and laser beam are selected, micron order movement is carried out using hot spot or carrier, using straight
Line style inwardly gradual point by point scanning, most Sapphire Substrate and epitaxial layer completely separate at last.
Further improve of the invention is, in step 4), in addition to using the overlapping irradiation stripping mode of hot spot, and adopts
Laser lift-off is carried out to epitaxial layer with dual-beam radiation mode.
Further improve of the invention is that the area of laser facula overlapping region is adjustable between 10%-90% scopes.
Of the invention further improve is, in step 4), the processing mode of laser be according to ecto-entad linear pattern gradually
Enter mode and point by point scanning hot spot is moved with micron order.
Further improve of the invention is that hot spot uses a variety of beam irradiation modes, and uses whether there is weight between hot spot
Folded mode realizes Sapphire Substrate laser lift-off, and a variety of beam irradiation modes realize that laser is shelled using single beam or double beam type
From.
Further improve of the invention is that laser is pulse or continuous laser source, and its hot spot is square or rectangle,
Size dimension is in some tens of pm to adjustable between several millimeters.
Of the invention further improve be, ecto-entad linear pattern progressive mode according to clockwise or counterclockwise,
It is scanned point by point according to square or rectangle length of side ecto-entad.
Further improve of the invention is that Laser Processing hot spot micron order displacement is tens of to several millimeters scope
It is interior adjustable.
Further improve of the invention is that micron order is moved through laser facula movement or carrier movement to realize.
The present invention has the advantage that：
Relative to existing horizontally or vertically reciprocating Sapphire Substrate laser lift-off technique, the present invention is using according to by outer
Inside linear pattern progressive mode simultaneously moves progress point by point scanning to realize the stripping of Sapphire Substrate with micron order.Its advantage is to fill
Divide and utilize existing equipment technological ability, reduce and transformation and the establishment of complicated mobile process are carried out to board hardware, can batch processing
Sample, not only reduce process complexity；Simultaneously using the point by point scanning mode of ecto-entad, considerably reduce and peel off moment
Device performance degradation caused by interface high pressure nitrogen impact and two kinds of influences of stress release are possible, improves product and technique is good
Rate, by process certification, under the conditions of existing single beam laser stripping technology, its stripping technology yield can be lifted 10% with
On, it is adapted to use large-scale production.
Brief description of the drawings
Fig. 1 is Sapphire Substrate of the present invention and its epitaxial layer structure schematic diagram
Fig. 2 is laser-stripping method schematic diagram in specific embodiment 1.
Fig. 3 is laser-stripping method schematic diagram in specific embodiment 2.
In figure, 100- Sapphire Substrates, 101- epitaxial layers, 102- laser beams.
Embodiment
The present invention will be further described with specific embodiment below in conjunction with the accompanying drawings.
Embodiment 1：
A kind of gradual micron order Sapphire Substrate laser lift-off provided by the invention, specifically includes following steps：
(1) gallium nitride based LED epitaxial layer 101 is prepared using epitaxial growth method in Sapphire Substrate 100 first, the extension
Layer 101 its gross thickness control is in 5-10 microns；Including cushion Buffer layer, unintentional doped layer U-GaN, heavy doping N-
GaN, MQW MQW, electronic barrier layer EBL, heavy doping P-GaN.Epitaxial growth method can be metallochemistry vapour deposition,
Laser assisted molecular beam epitaxy, laser splash, or hydride vapor-phase epitaxy.The epitaxial film of deposit can be amorphous, polycrystalline or
Mono-crystalline structures, the Sapphire Substrate including but not limited to one kind in minute surface or microscale/nanoscale graphical sapphire substrate,
Its preferred scheme is minute surface Sapphire Substrate；The epitaxial layer is included with the material system group such as GaN/InGaN/AlGaN/AlInGaN
Direction it is reciprocal continuous it is laddering into LED epitaxial structure in one or more, its preferred scheme is GaN/InGaN.
(2) prepare layer of metal indium in the surface thermal evaporation of epitaxial layer 101, thickness at 1 micron between some tens of pm, then
It is heated near fusing point, transfer substrate is pressed on the indium metal of epitaxial layer 101, cooling makes epitaxial layer 101 and turned
Substrate is moved to be bonded together.
(3) it is square using the single beam PRK 102 that wavelength is 248nm, laser facula, the hot spot length of side is
2mmX2mm, since wafer outermost, mobile spacing is also 2mmX2mm, progressive along straight line according to clockwise direction ecto-entad
(as shown in Figure 2) is peeled off in formula point by point scanning.
(4) after completing laser lift-off program, the Sapphire Substrate completely stripped out is removed, with the salt that volume ratio is 1: 1
Gallium nitride interface after acid solution clean stripping, cleaned up with deionized water and blow the peel sample with nitrogen, it is final to obtain
Epitaxial layer of gallium nitride after completely stripping.
Embodiment 2：
A kind of gradual micron order Sapphire Substrate laser lift-off provided by the invention, specifically includes following steps：
(1) aluminum gallium nitride epitaxial layer 101 is prepared using epitaxial growth method in Sapphire Substrate 100 first, the epitaxial layer
101 its gross thickness are controlled in 5-10 microns；Including cushion Buffer layer, AlN layers, superlattice structure SL, heavy doping N-
AlGaN, MQW MQW, P-AlGaN, heavy doping P-GaN contact layers.Epitaxial growth method can be that metallochemistry gas phase is sunk
Product, laser assisted molecular beam epitaxy, laser splash, or hydride vapor-phase epitaxy.The epitaxial film of deposit can be amorphous, more
Brilliant or mono-crystalline structures, the Sapphire Substrate is including but not limited in minute surface or microscale/nanoscale graphical sapphire substrate
One kind, its preferred scheme are micron order size graphical sapphire substrates；The epitaxial layer is included with GaN/AlN/AlGaN/
One or more in the LED epitaxial structure of the material systems such as AlInGaN composition, its preferred scheme AlN/AlGaN.
(2) adhesive layer is prepared using electron beam and thermal evaporation process on the epitaxial layer 101, its structure is Ni/Ag/Ti/
Au/AuSn, its gross thickness are 0.9-10 microns (Ni thickness rangesAg thickness ranges 150-300nm, Ti thickness model
Enclose 100-500nm, Au thickness ranges 200nm-5um, AuSn thickness range 500nm-5um)；Equally electricity is utilized on transfer substrate
Beamlet and thermal evaporation process prepare adhesive layer, and its structure is Ti/Au/AuSn, and its gross thickness is 0.8-10 microns (Ti thickness ranges
100-500nm, Au thickness range 200nm-5um, AuSn thickness range 500nm-5um), the adhesion-layer materials include but is not limited to
One or more in the metal materials such as indium, nickel, titanium, silver, aluminium, gold, platinum, golden tin, its preferred scheme is titanium, gold, golden tin composite bed,
The transfer substrate includes but is not limited to Si, SiC, AlSi, Cu, CuMo, CuW, or the machine of conductive heat conducting material thermal finalization again
Tool substrate of good performance, its preferred scheme are CuW and Si.
(3) wafer bonding equipment is utilized, under the bonding pressure, bonding temperature and process time of setting, utilizes epitaxial layer
101 and two layers of adhesive layer of transfer substrate pressed together by eutectic bonding mode, realize epitaxial layer of gallium nitride and
Transfer substrate is joined together to form integral material.
(4) the dual-beam PRK 102 that wavelength is 193nm is recycled, laser facula is square, and the hot spot length of side is
1mmX1mm, since wafer outermost, proportionally moved for 50% overlapping radiation mode, according to clockwise
Ecto-entad peels off (as shown in Figure 3) along the gradual point by point scanning of straight line.
(5) after completing laser lift-off program, the Sapphire Substrate completely stripped out is removed, it is clear with acetic acid or oxalic acid solution
The aluminum gallium nitride interface washed after peeling off, is cleaned up with deionized water and blows the peel sample with nitrogen, finally completely stripped
Epitaxial layer of gallium nitride afterwards.
The present invention uses optimization design thinking, and the reciprocating laser of original relatively simple horizontal or vertical direction is shelled
Improved, reduced in original laser lift-off because peeling off moment because of high pressure nitrogen impact or stress release pair from mode
Outside the influence of adjacent area, at the same also simplify other it is existing high to equipment requirement using round or arc line type stripping technology and
The problems such as program complexity is higher, technique and product yield can be improved.This method is that epitaxial layer and Sapphire Substrate are peeled off and carried
A kind of new technical scheme has been supplied, a kind of technology of high technology reliability is provided to make III-N series of vertical structure devices
Approach.
Claims (9)
1. a kind of gradual micron order Sapphire Substrate laser lift-off, it is characterised in that comprise the following steps：
1) growth of epitaxial layer (101) is completed in Sapphire Substrate (100), carrying out unit area to the epitaxial layer (101) draws
Divide and form raceway groove, hard or compliant conductive insulating barrier are prepared in the raceway groove between epitaxial layer unit area, then in epitaxial layer
(101) first layer adhesive layer is prepared on surface；
2) in whole face, transfer substrate prepares second layer adhesive layer；
3) first layer adhesive layer and second layer adhesive layer are adhered to each other, so as to which transfer substrate and epitaxial layer are connected into one
Rise；
4) hot spot pattern, laser energy and laser beam are selected, micron order movement is carried out using hot spot or carrier, using linear pattern
Inside gradual point by point scanning, most Sapphire Substrate (100) and epitaxial layer (101) completely separate at last.
A kind of 2. gradual micron order Sapphire Substrate laser lift-off according to claim 1, it is characterised in that step
It is rapid 4) in, in addition to using hot spot it is overlapping irradiation stripping mode, and using dual-beam radiation mode to epitaxial layer (101) carry out
Laser lift-off.
3. a kind of gradual micron order Sapphire Substrate laser lift-off according to claim 2, it is characterised in that swash
The area of light hot spot overlapping region is adjustable between 10%-90% scopes.
A kind of 4. gradual micron order Sapphire Substrate laser lift-off according to claim 1, it is characterised in that step
It is rapid 4) in, the processing mode of laser (102) is to move point by point scanning light according to ecto-entad linear pattern progressive mode with micron order
Spot.
A kind of 5. gradual micron order Sapphire Substrate laser lift-off according to claim 1, it is characterised in that light
Spot uses a variety of beam irradiation modes, and being used between hot spot has non-overlapping manner to realize Sapphire Substrate laser lift-off, a variety of
Beam irradiation mode realizes laser lift-off using single beam or double beam type.
6. a kind of gradual micron order Sapphire Substrate laser lift-off according to claim 1, it is characterised in that swash
Light is pulse or continuous laser source, and its hot spot is square or rectangle, and size dimension is in some tens of pm between several millimeters
It is adjustable.
A kind of 7. gradual micron order Sapphire Substrate laser lift-off according to claim 6, it is characterised in that by
Linear pattern progressive mode enters point by point according to clockwise or counterclockwise according to square or rectangle length of side ecto-entad outside to inside
Row scanning.
8. a kind of gradual micron order Sapphire Substrate laser lift-off according to claim 1, it is characterised in that swash
Light processes hot spot micron order displacement tens of to adjustable in the range of several millimeters.
9. a kind of gradual micron order Sapphire Substrate laser lift-off according to claim 1, it is characterised in that micro-
Meter level is moved through laser facula movement or carrier movement to realize.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710776207.1A CN107622977B (en) | 2017-08-31 | 2017-08-31 | Progressive laser stripping process for micron-sized sapphire substrate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710776207.1A CN107622977B (en) | 2017-08-31 | 2017-08-31 | Progressive laser stripping process for micron-sized sapphire substrate |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107622977A true CN107622977A (en) | 2018-01-23 |
| CN107622977B CN107622977B (en) | 2020-05-22 |
Family
ID=61089223
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710776207.1A Active CN107622977B (en) | 2017-08-31 | 2017-08-31 | Progressive laser stripping process for micron-sized sapphire substrate |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107622977B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109545931A (en) * | 2018-12-17 | 2019-03-29 | 佛山市国星半导体技术有限公司 | A kind of vertical structure LED wafer and stripping means |
| CN112750716A (en) * | 2019-10-29 | 2021-05-04 | 成都辰显光电有限公司 | Stripping device and stripping method for micro-element |
| WO2023273373A1 (en) * | 2021-06-28 | 2023-01-05 | 厦门士兰明镓化合物半导体有限公司 | Deep-ultraviolet led chip having a vertical structure, manufacturing method, and epitaxial structure |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1779900A (en) * | 2004-11-23 | 2006-05-31 | 北京大学 | Large-area and low-power laser stripping method for GaN-base epitaxial layer |
| CN101555627A (en) * | 2009-04-30 | 2009-10-14 | 苏州纳晶光电有限公司 | Laser peeling method of gallium nitride-based epitaxial film |
| CN101879657A (en) * | 2009-05-08 | 2010-11-10 | 东莞市中镓半导体科技有限公司 | Solid laser lift-off equipment and method |
| CN103839777A (en) * | 2014-03-11 | 2014-06-04 | 中国科学院半导体研究所 | Large area continuous lossless laser stripping method for gallium nitride film |
| CN103943741A (en) * | 2013-01-17 | 2014-07-23 | 易美芯光（北京）科技有限公司 | Semiconductor light emitting device preparation method based on laser stripping |
-
2017
- 2017-08-31 CN CN201710776207.1A patent/CN107622977B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1779900A (en) * | 2004-11-23 | 2006-05-31 | 北京大学 | Large-area and low-power laser stripping method for GaN-base epitaxial layer |
| CN101555627A (en) * | 2009-04-30 | 2009-10-14 | 苏州纳晶光电有限公司 | Laser peeling method of gallium nitride-based epitaxial film |
| CN101879657A (en) * | 2009-05-08 | 2010-11-10 | 东莞市中镓半导体科技有限公司 | Solid laser lift-off equipment and method |
| CN103943741A (en) * | 2013-01-17 | 2014-07-23 | 易美芯光（北京）科技有限公司 | Semiconductor light emitting device preparation method based on laser stripping |
| CN103839777A (en) * | 2014-03-11 | 2014-06-04 | 中国科学院半导体研究所 | Large area continuous lossless laser stripping method for gallium nitride film |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109545931A (en) * | 2018-12-17 | 2019-03-29 | 佛山市国星半导体技术有限公司 | A kind of vertical structure LED wafer and stripping means |
| CN112750716A (en) * | 2019-10-29 | 2021-05-04 | 成都辰显光电有限公司 | Stripping device and stripping method for micro-element |
| WO2023273373A1 (en) * | 2021-06-28 | 2023-01-05 | 厦门士兰明镓化合物半导体有限公司 | Deep-ultraviolet led chip having a vertical structure, manufacturing method, and epitaxial structure |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107622977B (en) | 2020-05-22 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI455345B (en) | Light emitting diode having vertical topology and method of making the same | |
| TWI467798B (en) | Method for making light emitting diode chip | |
| TWI422068B (en) | Roughening method and method for manufacturing light emitting diode having roughened surface | |
| KR101438818B1 (en) | light emitting diode | |
| CN104701427B (en) | A kind of light emitting diode (LED) chip with vertical structure preparation method | |
| CN105742417B (en) | A kind of vertical LED chip structure and preparation method thereof | |
| CN105247695A (en) | Semiconductor light-emitting element and semiconductor light-emitting device | |
| JP2008047860A (en) | Method of forming rugged surface and method of manufacturing gallium nitride light-emitting diode device using the same | |
| CN102097542A (en) | Method of forming vertical structure light emitting diode with heat exhaustion structure | |
| JP2010219310A (en) | Optical device and optical device structure | |
| CN107195734A (en) | A kind of micro LED preparation method | |
| CN107579139B (en) | A kind of manufacturing method of vertical structure semiconductor devices | |
| CN107622977A (en) | A kind of gradual micron order Sapphire Substrate laser lift-off | |
| CN101877377B (en) | Epitaxial wafer of discrete light-emitting diode and manufacturing method thereof | |
| CN113193085A (en) | Microstructure light-emitting diode with PIN tunneling junction and manufacturing method thereof | |
| CN107731975B (en) | Nanotube LED and manufacturing method thereof | |
| CN103730549A (en) | SiC-substrate-based perpendicular structural GaN-based ultraviolet LED (Light Emitting Diode) and production method thereof | |
| CN104465899A (en) | Preparation method for LED perpendicular structure | |
| KR101428066B1 (en) | vertical structured group 3 nitride-based light emitting diode and its fabrication methods | |
| CN201667345U (en) | High-power GaN-based LED epitaxial structure suitable for laser stripping | |
| KR101480551B1 (en) | vertical structured group 3 nitride-based light emitting diode and its fabrication methods | |
| KR101239852B1 (en) | GaN compound semiconductor light emitting element | |
| JP2010165983A (en) | Light-emitting chip integrated device and method for manufacturing the same | |
| CN103840073B (en) | Inverted light-emitting diode (LED) device and its manufacture method | |
| CN106328776A (en) | Preparation method of vertical-structure purple light LED chip |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |