CN107742606B - Structure for bonding wafers and preparation method thereof - Google Patents
Structure for bonding wafers and preparation method thereof Download PDFInfo
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- CN107742606B CN107742606B CN201711030930.1A CN201711030930A CN107742606B CN 107742606 B CN107742606 B CN 107742606B CN 201711030930 A CN201711030930 A CN 201711030930A CN 107742606 B CN107742606 B CN 107742606B
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- 235000012431 wafers Nutrition 0.000 title abstract description 204
- 238000002360 preparation method Methods 0.000 title abstract description 12
- 239000007789 gas Substances 0.000 claims abstract description 61
- 238000004140 cleaning Methods 0.000 claims abstract description 44
- 229910052751 metal Inorganic materials 0.000 claims abstract description 38
- 239000002184 metal Substances 0.000 claims abstract description 38
- 229920002120 photoresistant polymer Polymers 0.000 claims abstract description 34
- 238000005530 etching Methods 0.000 claims abstract description 27
- TWNQGVIAIRXVLR-UHFFFAOYSA-N oxo(oxoalumanyloxy)alumane Chemical compound O=[Al]O[Al]=O TWNQGVIAIRXVLR-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000001301 oxygen Substances 0.000 claims abstract description 19
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 19
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 18
- 238000000137 annealing Methods 0.000 claims abstract description 10
- 230000003647 oxidation Effects 0.000 claims abstract description 10
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 10
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims description 110
- 238000000034 method Methods 0.000 claims description 61
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 claims description 50
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 36
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 claims description 35
- 239000008367 deionised water Substances 0.000 claims description 35
- 229910021641 deionized water Inorganic materials 0.000 claims description 35
- 239000011259 mixed solution Substances 0.000 claims description 35
- 229910052782 aluminium Inorganic materials 0.000 claims description 33
- VHUUQVKOLVNVRT-UHFFFAOYSA-N Ammonium hydroxide Chemical compound [NH4+].[OH-] VHUUQVKOLVNVRT-UHFFFAOYSA-N 0.000 claims description 30
- 235000011114 ammonium hydroxide Nutrition 0.000 claims description 30
- 238000000151 deposition Methods 0.000 claims description 20
- 238000002791 soaking Methods 0.000 claims description 15
- 239000003960 organic solvent Substances 0.000 claims description 13
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 12
- 238000001035 drying Methods 0.000 claims description 12
- 239000000126 substance Substances 0.000 claims description 11
- 238000010438 heat treatment Methods 0.000 claims description 10
- 239000007788 liquid Substances 0.000 claims description 10
- 238000005406 washing Methods 0.000 claims description 10
- 238000004519 manufacturing process Methods 0.000 claims description 9
- 238000005498 polishing Methods 0.000 claims description 9
- 238000005201 scrubbing Methods 0.000 claims description 9
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 7
- 238000000231 atomic layer deposition Methods 0.000 claims description 7
- 239000000460 chlorine Substances 0.000 claims description 7
- 229910052801 chlorine Inorganic materials 0.000 claims description 7
- FAQYAMRNWDIXMY-UHFFFAOYSA-N trichloroborane Chemical compound ClB(Cl)Cl FAQYAMRNWDIXMY-UHFFFAOYSA-N 0.000 claims description 7
- 229910021645 metal ion Inorganic materials 0.000 claims description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 239000002245 particle Substances 0.000 claims description 6
- 238000005229 chemical vapour deposition Methods 0.000 claims description 5
- 239000011248 coating agent Substances 0.000 claims description 5
- 238000000576 coating method Methods 0.000 claims description 5
- 238000000313 electron-beam-induced deposition Methods 0.000 claims description 5
- 238000000623 plasma-assisted chemical vapour deposition Methods 0.000 claims description 5
- 238000004528 spin coating Methods 0.000 claims description 5
- 238000004544 sputter deposition Methods 0.000 claims description 5
- 238000001039 wet etching Methods 0.000 claims description 5
- 239000011800 void material Substances 0.000 abstract description 5
- 238000011161 development Methods 0.000 abstract description 3
- 238000001704 evaporation Methods 0.000 abstract 1
- 239000010410 layer Substances 0.000 description 30
- PNEYBMLMFCGWSK-UHFFFAOYSA-N Alumina Chemical compound [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 9
- OKKJLVBELUTLKV-UHFFFAOYSA-N Methanol Chemical compound OC OKKJLVBELUTLKV-UHFFFAOYSA-N 0.000 description 9
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 6
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 description 6
- 239000000463 material Substances 0.000 description 5
- 230000009286 beneficial effect Effects 0.000 description 4
- 230000017525 heat dissipation Effects 0.000 description 4
- 239000000758 substrate Substances 0.000 description 4
- 230000003746 surface roughness Effects 0.000 description 4
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 description 3
- 230000008021 deposition Effects 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 229910018516 Al—O Inorganic materials 0.000 description 2
- 230000004888 barrier function Effects 0.000 description 2
- UMIVXZPTRXBADB-UHFFFAOYSA-N benzocyclobutene Chemical compound C1=CC=C2CCC2=C1 UMIVXZPTRXBADB-UHFFFAOYSA-N 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 230000008878 coupling Effects 0.000 description 2
- 238000010168 coupling process Methods 0.000 description 2
- 238000005859 coupling reaction Methods 0.000 description 2
- 238000009792 diffusion process Methods 0.000 description 2
- 239000012212 insulator Substances 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 239000004065 semiconductor Substances 0.000 description 2
- 238000012695 Interfacial polymerization Methods 0.000 description 1
- 229910004298 SiO 2 Inorganic materials 0.000 description 1
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 1
- 238000013459 approach Methods 0.000 description 1
- 239000012459 cleaning agent Substances 0.000 description 1
- 230000007797 corrosion Effects 0.000 description 1
- 238000005260 corrosion Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000032798 delamination Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000004377 microelectronic Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 230000005693 optoelectronics Effects 0.000 description 1
- 231100000719 pollutant Toxicity 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000011241 protective layer Substances 0.000 description 1
- 238000011160 research Methods 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000010703 silicon Substances 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 239000002904 solvent Substances 0.000 description 1
- 238000007740 vapor deposition Methods 0.000 description 1
- 239000012855 volatile organic compound Substances 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/20—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy
- H01L21/2003—Deposition of semiconductor materials on a substrate, e.g. epitaxial growth solid phase epitaxy characterised by the substrate
- H01L21/2007—Bonding of semiconductor wafers to insulating substrates or to semiconducting substrates using an intermediate insulating layer
Landscapes
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Cleaning Or Drying Semiconductors (AREA)
Abstract
The invention discloses a structure for bonding wafers and a preparation method thereof, and mainly solves the technical problems of low bonding strength and high bonding void ratio in the prior art. The structure of the bonded wafer and the preparation method thereof are characterized in that metal Al is deposited by cleaning and evaporating two wafers to be bonded, photoresist is coated on the surface of any wafer in a spin mode, soft baking, UV exposure and photoresist development are carried out, an equidistant channel is formed by etching, bonding is carried out at a low temperature in an oxygen environment and annealing is carried out at a low temperature to obtain the wafer bonding structure, the wafer bonding structure comprises an upper wafer layer and a lower wafer layer, and oxidation and bonding between the two wafer layers are carried out in a contract mode, so that the bonded surface is provided with a technical scheme of a gas channel mixed by aluminum oxide and gas. Can be used for low temperature bonding of wafers.
Description
Technical Field
The invention relates to the technical field of wafer bonding, in particular to a structure for bonding wafers and a preparation method thereof.
Background
With the development of integrated circuits, wafer bonding has proven to be a direct and efficient method for assembling, processing and manufacturing substrate materials, and has found wide application in the semiconductor field, the microelectronics field, the MEMS field and the manufacturing field of optoelectronic devices, and particularly, the low-temperature direct bonding mode is more deeply embodied in the silicon-on-insulator (SOI) manufacturing process.
Wafer bonding refers to the fact that two wafers with flat and clean surfaces can be connected with each other through chemical bonds on the surfaces under certain conditions. The wafer bonding has the compatibility and flexibility of a semiconductor process, and in the bonding process, BCB (benzocyclobutene) is generally adopted as a bonding medium material, and the bonding material has the defect of poor heat dissipation, so that more bubbles can be generated at a bonding interface, and the bonding quality problem of low bonding strength is caused; these bonding quality problems tend to create interfacial voids that cause scattering or loss of optical coupling. Therefore, the prior wafer bonding technology still has the problems of high void ratio and low bonding strength.
The research shows that Al 2 O 3 Is excellent in heat dissipation properties and diffusion barrier properties. Thus, for adhesion and 3D integrated circuit applications, al 2 O 3 Is becoming increasingly popular. The use of atomic layer deposition (AlD) Al has been demonstrated in III-V insulator on Silicon (SOI) structures 2 O 3 To In0.53Ga0.47As-OI and Al 2 O 3 Excellent performance is obtained at the bottom interface of the buried oxide.
However, the bonding quality is still limited by interfacial voids that may cause optical coupling scattering or loss. These voids are gaseous byproducts generated by interfacial polymerization (consisting essentially of H 2 And H 2 O molecular composition) several approaches have been investigated at the residual bonding interface to suppress the interface void density. InP-on-SOI has been shown to use vertical exhaust gas channels (VOCs) in bonding to absorb and diffuse gaseous byproducts into the bondPorous embedded SiO 2 In the layer. While void-free bonding has been achieved, it has been found that these absorbed gases can lead to severe film delamination during post-bonding at high temperatures.
Disclosure of Invention
The invention aims to solve the technical problems of high void ratio and low bonding strength in the prior art, and provides a novel bonding wafer structure and a preparation method thereof.
In order to solve the technical problems, the technical scheme adopted is as follows:
the utility model provides a structure of bonding wafer, includes first wafer and second wafer, the second wafer is located the top of first wafer, be provided with the intermediate level between first wafer and the second wafer, the intermediate level includes gas passage and aluminium oxide layer, gas passage sets up in aluminium oxide layer, and gas passage transversely runs through the aluminium oxide layer.
Further: the gas channels are equidistant gas channels formed by etching the aluminum oxide layer through mixed gas.
Further: the equidistant gas channels are groove-shaped channels.
The preparation method of the structure of the bonding wafer comprises the following steps:
A. cleaning the first wafer and the second wafer, and drying;
B. depositing metal aluminum on the surfaces of the first wafer and the second wafer;
C. uniformly coating photoresist on the surface of the first wafer or the second wafer by adopting a spin coating method;
D. sequentially performing soft baking, mask plate adding, ultraviolet light exposure and photoresist developing processes on the first wafer or the second wafer coated with the photoresist; the soft baking condition is that the soft baking is carried out in a vacuum hot plate, the baking temperature is 80-120 ℃, and the baking time is 30-60 s;
E. b, etching the first wafer or the second wafer with the photoresist to form a gas channel, and mutually contacting the bonding surface of the first wafer and the bonding surface of the second wafer to perform pre-bonding, wherein the bonding surface of the first wafer and the bonding surface of the second wafer are both metal aluminum layers formed in the step B;
F. removing the residual photoresist by wet etching;
G. placing the first wafer and the second wafer into a bonding machine to bond at a low temperature in an oxygen environment, and enabling oxygen molecules to enter a bonding surface of the first wafer and a bonding surface of the second wafer through the gas channel to naturally oxidize the metal aluminum layer into aluminum oxide; the bonding temperature is 100-400 ℃ and the bonding pressure is 100-1000 Kg;
H. annealing at low temperature; the annealing temperature is 100-400 ℃.
Further: the cleaning in the step A is an RCA wet chemical cleaning method, wherein the cleaning liquid adopted by the RCA wet chemical cleaning method comprises a mixed solution of an organic solvent, sulfuric acid and hydrogen peroxide and a mixed solution of ammonia water, hydrogen peroxide and deionized water; in a mixed solution of sulfuric acid and hydrogen peroxide, the concentration of the sulfuric acid is 96%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the sulfuric acid to the hydrogen peroxide is 4:1; in the mixed solution of the ammonia water, the hydrogen peroxide and the deionized water, the concentration of the ammonia water is 29%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the three liquids is as follows: ammonia water, hydrogen peroxide and deionized water in the ratio of 1:1:5;
the cleaning method comprises the following steps: removing oil stains on the surfaces of the first wafer and the second wafer by adopting the organic solvent; ultrasonically cleaning particles adsorbed on the surfaces of the first wafer and the second wafer; heating the mixed solution of sulfuric acid and hydrogen peroxide to 95 ℃, soaking the first wafer and the second wafer for 20 minutes, and rapidly washing the soaked first wafer and second wafer with deionized water to remove metal ions; heating the mixed solution of ammonia water, hydrogen peroxide and deionized water to 80 ℃, soaking the first wafer and the second wafer for 15 minutes, keeping the temperature of the mixed solution of ammonia water, hydrogen peroxide and deionized water unchanged in the soaking process, and then rapidly washing the soaked first wafer and second wafer by using deionized water.
Further: and (C) drying in the step A, namely drying by adopting nitrogen.
Further: and (C) scrubbing and/or polishing the first wafer and the second wafer after cleaning.
Further: the method for depositing the metal aluminum in the step B adopts one of a chemical vapor deposition method, a plasma enhanced chemical vapor deposition method, an atomic layer deposition method, sputtering, an electron beam deposition method and a laser pulse deposition method, and the thickness of the metal aluminum deposit is 20nm.
Further: the gas channels in the step E are groove-shaped equidistant gas channels.
Further: the etching in the step E adopts mixed gas of boron trichloride and chlorine to etch; the etching is performed in a cavity at the temperature of 60 ℃, and the etching time is 60-80 s.
The invention has the beneficial effects that:
firstly, aluminum oxide has better heat radiation property and diffusion barrier property, a gas channel is formed by etching in the plane of a bonding wafer, and metal aluminum is naturally oxidized into aluminum oxide at the same time, so that higher bonding strength is achieved and the bonding wafer has better heat radiation property; on the other hand, the gas channel in the bonding wafer plane can effectively remove gas, so that bubbles in the bonding wafer are reduced, and the void fraction is reduced.
And the groove-shaped equidistant gas channels are beneficial to the entry of oxygen to promote oxidation, so that bonding and oxidation are carried out simultaneously, and the uniformity of oxygen entry can be ensured.
And thirdly, cleaning the wafer to clean the greasy dirt, adsorbed particles and metal ions on the surface of the wafer, so that the wafer is clean and bubbles are avoided during bonding.
And the fourth effect is that the nitrogen is adopted to keep the surface of the wafer clean, so that new pollutants are avoided.
And fifthly, depositing metal aluminum on the surface of the wafer, so that the metal aluminum is exposed in the air and is naturally oxidized to form an aluminum oxide protective layer, and the oxidation and bonding are simultaneously carried out, so that the formed Al-O bond is in a natural oxidation mode, and the bonding strength is improved to a great extent.
The soft baking can remove the solvent for cleaning, enhance the adhesiveness in the bonding process, release the internal stress of the photoresist and prevent the photoresist from polluting equipment.
And the mixed gas of boron trichloride and chlorine is adopted to finish etching, and the boron trichloride is a good cleaning agent for oxygen and water, so that oxide aluminum oxide can be prevented from being formed on the surface of metal aluminum in the corrosion process.
And the method has the advantages that the damage to the temperature-sensitive device or structure is avoided by adopting the low-temperature bonding and low-temperature annealing technology, and the bonding of any two substrates or devices is facilitated.
Effect nine, scrubbing and/or polishing two wafers, specifically includes when the roughness of the wafer surface is large (typically greater than 2 nm), making the surface roughness suitable for die bonding (typically less than 1 nm).
The effect 10, the thickness of the metal aluminum deposit is 20nm, so that the number of bonded voids is smaller and the size is smaller.
In summary, according to the bonded wafer structure and the preparation method thereof, oxidation and bonding between the first wafer and the second wafer are performed in a contract, the formed Al-O bond is in a natural oxidation mode, and the bonding energy is high; and a groove gas channel is formed in the middle layer between the first wafer and the second wafer, namely the gas channel is beneficial to the entry of oxygen to promote oxidation, and meanwhile, the gap generated by bonding the wafers is reduced; by Al 2 O 3 As a bonding medium to facilitate heat dissipation of the formed device; the low-temperature bonding technology avoids the damage to the temperature-sensitive device or structure, and is beneficial to bonding any two substrates or devices. Therefore, the structure for bonding wafers and the preparation method thereof reduce gaps among the wafers, improve bonding strength and improve heat dissipation of devices manufactured based on SOI structures.
Drawings
FIG. 1 is a schematic cross-sectional view of a substrate wafer prior to low temperature bonding.
FIG. 2 is a schematic cross-sectional view of the vapor deposition of aluminum metal on the first wafer and the second wafer after the cleaning step is completed.
FIG. 3 is a schematic cross-sectional view of a gas channel formed by etching either one of a first wafer and a second wafer to form equally spaced grooves.
Figures 3a-3d are schematic cross-sectional views of the specific process of stepwise forming grooves of figure 3.
FIG. 4 is a graph of the time at O 2 Bonding cross-section schematic in the environment.
Fig. 5 is a schematic cross-sectional view of a bonded wafer structure after bonding is completed.
Description of the drawings:
1-first wafer, 2-second wafer, 3-metal aluminum, 4-photoresist, 5-oxygen environment, 6-ultraviolet light, 7-mask, 8-aluminum oxide layer, 9-gas channel, 10-boron trichloride and chlorine mixed gas
Detailed Description
The invention will be further described with reference to the drawings and examples.
The present invention will be described in further detail with reference to the following examples in order to make the objects, technical solutions and advantages of the present invention more apparent. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the scope of the invention.
Example 1:
as shown in fig. 1, the present embodiment provides a structure for bonding wafers, including a first wafer 1 and a second wafer 2, where the first wafer 1 is located at a bottom layer, an intermediate layer is located above the first wafer 1, the intermediate layer includes a gas channel 9 and an aluminum oxide layer 8, and the second wafer 2 is located above the intermediate layer; the gas passages 9 are groove-like equidistant gas passages formed by etching a mixed gas.
The preparation method of the structure of the bonding wafer comprises the following steps:
A. cleaning and drying the first wafer 1 and the second wafer 2; the cleaning adopts an RCA wet chemical cleaning method, and the cleaning liquid adopted by the RCA wet chemical cleaning method comprises a mixed solution of an organic solvent, sulfuric acid and hydrogen peroxide and a mixed solution of ammonia water, hydrogen peroxide and deionized water; the organic solvent comprises one or more of isopropanol, absolute ethanol, methanol and acetone; in the mixed solution of sulfuric acid and hydrogen peroxide, the concentration of the sulfuric acid is 96%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the sulfuric acid to the hydrogen peroxide is 4:1; in the mixed solution of ammonia water, hydrogen peroxide and deionized water, the concentration of the ammonia water is 29%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the three liquids is as follows: ammonia water, hydrogen peroxide and deionized water in the ratio of 1:1:5; the cleaning method comprises the following steps: removing greasy dirt on the surfaces of the first wafer 1 and the second wafer 2 by adopting an organic solvent; ultrasonically cleaning particles adsorbed on the surfaces of the first wafer 1 and the second wafer 2; heating the mixed solution of sulfuric acid and hydrogen peroxide to 95 ℃, soaking the first wafer 1 and the second wafer 2 for 20 minutes, and rapidly washing the soaked first wafer 1 and second wafer 2 with deionized water to remove metal ions; heating a mixed solution of ammonia water, hydrogen peroxide and deionized water to 80 ℃, soaking a first wafer 1 and a second wafer 2 for 15 minutes, keeping the temperature of the mixed solution of ammonia water, hydrogen peroxide and deionized water unchanged in the soaking process, and then rapidly washing the soaked first wafer 1 and second wafer 2 by using deionized water; scrubbing and/or polishing the rough first wafer 1 and the rough second wafer 2 after cleaning; roughness refers to a surface roughness greater than 2nm and less than 1nm after scrubbing and/or polishing; drying by adopting nitrogen;
B. depositing metal aluminum 3 on the surfaces of the first wafer 1 and the second wafer 2; the method for depositing the metal aluminum 3 adopts one of an organic metal chemical vapor deposition method, a plasma enhanced chemical vapor deposition method, an atomic layer deposition method, sputtering, an electron beam deposition method and a laser pulse deposition method, and the thickness of the metal aluminum deposition is 20nm; the method comprises the steps of carrying out a first treatment on the surface of the
C. Uniformly coating photoresist 4 on the surface of the first wafer 1 or the second wafer 2 by adopting a spin coating method;
D. sequentially carrying out soft baking on the first wafer 1 or the second wafer 2 coated with the photoresist 4, placing a mask 7 on the photoresist 4, and then carrying out exposure by ultraviolet light 6 and photoresist development; the soft baking condition is that the material is placed in a vacuum hot plate, the baking temperature is 80 ℃, and the baking time is 30s;
E. etching the first wafer 1 or the second wafer 2 with the photoresist 4 to form a gas channel 9, and contacting the bonding surface of the first wafer 1 with the bonding surface of the second wafer 2 for pre-bonding, wherein the bonding surface of the first wafer 1 and the bonding surface of the second wafer 2 are both metal aluminum layers formed in the step B; the etching is carried out by adopting mixed gas 10 of boron trichloride and chlorine; etching is performed in a cavity at the temperature of 60 ℃ for 60 seconds;
F. removing the residual photoresist 4 by wet etching;
G. the first wafer 1 and the second wafer 2 are placed into an oxygen environment 5 filled with oxygen in a bonding machine cavity to be bonded at low temperature, oxygen molecules enter a bonding surface of the first wafer 1 and a bonding surface of the second wafer 2 through a gas channel, and a metal aluminum layer is naturally oxidized into aluminum oxide 8; the bonding temperature is 100 ℃, and the bonding pressure is 100Kg;
example 2:
as shown in fig. 1, the present embodiment provides a structure for bonding wafers, which includes a first wafer 1 and a second wafer 2, wherein the first wafer 1 is located at a bottom layer, an intermediate layer is located above the first wafer 1, the intermediate layer includes a gas channel 9 and an aluminum oxide layer 8, and the second wafer 2 is located above the intermediate layer; the gas passages 9 are groove-like equidistant gas passages formed by etching a mixed gas.
The preparation method of the structure of the bonding wafer comprises the following steps:
A. cleaning and drying the first wafer 1 and the second wafer 2; the cleaning adopts an RCA wet chemical cleaning method, and the cleaning liquid adopted by the RCA wet chemical cleaning method comprises a mixed solution of an organic solvent, sulfuric acid and hydrogen peroxide and a mixed solution of ammonia water, hydrogen peroxide and deionized water; the organic solvent comprises one or more of isopropanol, absolute ethanol, methanol and acetone; in a mixed solution of sulfuric acid and hydrogen peroxide, the concentration of the sulfuric acid is 96%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the sulfuric acid to the hydrogen peroxide is 4:1; in the mixed solution of ammonia water, hydrogen peroxide and deionized water, the concentration of the ammonia water is 29%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the three liquids is as follows: ammonia water and hydrogen peroxide, deionized water=1:1:5; the cleaning method comprises the following steps: removing greasy dirt on the surfaces of the first wafer and the second wafer by adopting an organic solvent; ultrasonically cleaning particles adsorbed on the surfaces of the first wafer and the second wafer; heating the mixed solution of sulfuric acid and hydrogen peroxide to 95 ℃, soaking the first wafer and the second wafer for 20 minutes, and rapidly washing the soaked first wafer and second wafer with deionized water to remove metal ions; heating the mixed solution of ammonia water, hydrogen peroxide and deionized water to 80 ℃, soaking the first wafer and the second wafer for 15 minutes, keeping the temperature of the mixed solution of ammonia water, hydrogen peroxide and deionized water unchanged in the soaking process, and then rapidly washing the soaked first wafer and second wafer by using deionized water; scrubbing and/or polishing the rough first wafer and the rough second wafer after cleaning; roughness refers to a surface roughness greater than 2nm and less than 1nm after scrubbing and/or polishing; drying by adopting nitrogen;
B. depositing metal aluminum 3 on the surfaces of the first wafer 1 and the second wafer 2; the method for depositing the metal aluminum 3 adopts one of an organic metal chemical vapor deposition method, a plasma enhanced chemical vapor deposition method, an atomic layer deposition method, sputtering, an electron beam deposition method and a laser pulse deposition method, and the thickness of the metal aluminum deposition is 20nm; the method comprises the steps of carrying out a first treatment on the surface of the
C. Uniformly coating photoresist 4 on the surface of the first wafer 1 or the second wafer 2 by adopting a spin coating method;
D. sequentially carrying out soft baking on the first wafer 1 or the second wafer 2 coated with the photoresist 4, placing a mask 7 on the photoresist 4, and then exposing and developing the photoresist by using ultraviolet light 6; the soft baking condition is that the material is placed in a vacuum hot plate, the baking temperature is 120 ℃, and the baking time is 60s;
E. etching the first wafer 1 or the second wafer 2 with the photoresist 4 to form a gas channel 9, and contacting the bonding surface of the first wafer 1 with the bonding surface of the second wafer 2 for pre-bonding, wherein the bonding surface of the first wafer 1 and the bonding surface of the second wafer 2 are both metal aluminum layers formed in the step B; the etching is carried out by adopting mixed gas 10 of boron trichloride and chlorine; etching is performed in a cavity at the temperature of 60 ℃ for 80 seconds;
F. removing the residual photoresist 4 by wet etching;
G. the first wafer 1 and the second wafer 2 are put into a bonding machine to be bonded at low temperature in an oxygen environment 5; oxygen molecules enter the bonding surface of the first wafer 1 and the bonding surface of the second wafer 2 through the gas channel to naturally oxidize the metal aluminum layer into aluminum oxide 8; the bonding temperature is 400 ℃ and the bonding pressure is 1000Kg;
H. annealing at low temperature; the annealing temperature was 400 ℃.
Example 3:
as shown in fig. 1, the present embodiment provides a structure for bonding wafers, including a first wafer 1 and a second wafer 2, wherein the first wafer 1 is located at a bottom layer, a middle layer is located above the first wafer 1, the middle layer includes a gas channel 9 and an aluminum oxide 8 layer, and the second wafer 2 is located above the middle layer; the gas passages 9 are groove-like equidistant gas passages formed by etching a mixed gas.
The preparation method of the structure of the bonding wafer comprises the following steps:
A. cleaning and drying the first wafer 1 and the second wafer 2; the cleaning adopts an RCA wet chemical cleaning method, and the cleaning liquid adopted by the RCA wet chemical cleaning method comprises a mixed solution of an organic solvent, sulfuric acid and hydrogen peroxide and a mixed solution of ammonia water, hydrogen peroxide and deionized water; the organic solvent comprises one or more of isopropanol, absolute ethanol, methanol and acetone; in a mixed solution of sulfuric acid and hydrogen peroxide, the concentration of the sulfuric acid is 96%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the sulfuric acid to the hydrogen peroxide is 4:1; in the mixed solution of ammonia water, hydrogen peroxide and deionized water, the concentration of the ammonia water is 29%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the three liquids is as follows: ammonia water and hydrogen peroxide, deionized water=1:1:5; the cleaning method comprises the following steps: removing greasy dirt on the surfaces of the first wafer 1 and the second wafer 2 by adopting an organic solvent; ultrasonically cleaning particles adsorbed on the surfaces of the first wafer 1 and the second wafer 2; heating the mixed solution of sulfuric acid and hydrogen peroxide to 95 ℃, soaking the first wafer 1 and the second wafer 2 for 20 minutes, and rapidly washing the soaked first wafer 1 and second wafer 2 with deionized water to remove metal ions; heating a mixed solution of ammonia water, hydrogen peroxide and deionized water to 80 ℃, soaking a first wafer 1 and a second wafer 2 for 15 minutes, keeping the temperature of the mixed solution of ammonia water, hydrogen peroxide and deionized water unchanged in the soaking process, and then rapidly washing the soaked first wafer 1 and second wafer 2 by using deionized water; scrubbing and/or polishing the rough first wafer 1 and the rough second wafer 2 after cleaning; roughness refers to a surface roughness greater than 2nm and less than 1nm after scrubbing and/or polishing; drying by adopting nitrogen;
B. depositing metal aluminum 3 on the surfaces of the first wafer 1 and the second wafer 2; the method for depositing the metal aluminum 3 adopts one of an organic metal chemical vapor deposition method, a plasma enhanced chemical vapor deposition method, an atomic layer deposition method, sputtering, an electron beam deposition method and a laser pulse deposition method, and the thickness of the metal aluminum deposition is 20nm;
C. uniformly coating photoresist 4 on the surface of the first wafer 1 or the second wafer 2 by adopting a spin coating method;
D. sequentially carrying out soft baking on the first wafer 1 or the second wafer 2 coated with the photoresist 4, placing a mask 7 on the photoresist 4, and then exposing and developing the photoresist by using ultraviolet light 6; the soft baking condition is that the soft baking is carried out in a vacuum hot plate, the baking temperature is 100 ℃, and the baking time is 45s;
E. etching the first wafer 1 or the second wafer 2 with the photoresist 4 to form a gas channel 9, and contacting the bonding surface of the first wafer 1 with the bonding surface of the second wafer 2 for pre-bonding, wherein the bonding surface of the first wafer 1 and the bonding surface of the second wafer 2 are both metal aluminum layers formed in the step B; the etching is carried out by adopting mixed gas 10 of boron trichloride and chlorine; etching is performed in a cavity at the temperature of 60 ℃ for 70s;
F. removing the residual photoresist by wet etching;
G. the first wafer 1 and the second wafer 2 are put into a bonding machine to be bonded at low temperature in an oxygen environment 5; oxygen molecules enter the bonding surface of the first wafer 1 and the bonding surface of the second wafer 2 through the gas channel to naturally oxidize the metal aluminum layer into aluminum oxide 8; the bonding temperature is 250 ℃, and the bonding pressure is 200Kg-500Kg;
H. annealing at low temperature; the annealing temperature was 250 ℃.
While the foregoing describes the illustrative embodiments of the present invention so that those skilled in the art may understand the present invention, the present invention is not limited to the specific embodiments, and all inventive innovations utilizing the inventive concepts are herein within the scope of the present invention as defined and defined by the appended claims, as long as the various changes are within the spirit and scope of the present invention.
Claims (8)
1. A bonded wafer structure comprising a first wafer and a second wafer, characterized in that: the second wafer is positioned above the first wafer, an intermediate layer is arranged between the first wafer and the second wafer, the intermediate layer comprises a gas channel and an aluminum oxide layer, the gas channel is arranged in the aluminum oxide layer, and the gas channel transversely penetrates through the aluminum oxide layer; the gas channels are equidistant gas channels formed by etching the metal aluminum layer through mixed gas; the equidistant gas channels are groove-shaped channels;
the aluminum oxide layer is formed in the following manner:
the first step: depositing metal aluminum on the surfaces of the first wafer and the second wafer;
and a second step of: etching a first wafer or a second wafer with photoresist to form a gas channel, contacting a bonding surface of the first wafer with a bonding surface of the second wafer, and pre-bonding, wherein the bonding surface of the first wafer and the bonding surface of the second wafer are both metal aluminum layers formed in a first step;
and a third step of: placing the first wafer and the second wafer into a bonding machine to bond at a low temperature in an oxygen environment, and enabling oxygen molecules to enter a bonding surface of the first wafer and a bonding surface of the second wafer through the gas channel to naturally oxidize the metal aluminum layer into aluminum oxide; oxidation and bonding are performed simultaneously.
2. A method of fabricating a wafer bonded structure according to claim 1, comprising the steps of:
A. cleaning the first wafer and the second wafer, and drying;
B. depositing metal aluminum on the surfaces of the first wafer and the second wafer;
C. uniformly coating photoresist on the surface of the first wafer or the second wafer by adopting a spin coating method;
D. sequentially performing soft baking, mask plate adding, ultraviolet light exposure and photoresist developing processes on the first wafer or the second wafer coated with the photoresist; the soft baking condition is that the soft baking is carried out in a vacuum hot plate, the baking temperature is 80-120 ℃, and the baking time is 30-60 s;
E. etching a first wafer or a second wafer with photoresist to form a gas channel, contacting a bonding surface of the first wafer with a bonding surface of the second wafer, and pre-bonding, wherein the bonding surface of the first wafer and the bonding surface of the second wafer are both metal aluminum layers formed in a first step;
F. removing the residual photoresist by wet etching;
G. placing the first wafer and the second wafer into a bonding machine to bond at a low temperature in an oxygen environment, and enabling oxygen molecules to enter a bonding surface of the first wafer and a bonding surface of the second wafer through the gas channel to naturally oxidize the metal aluminum layer into aluminum oxide; oxidation and bonding are performed simultaneously;
H. annealing at low temperature; the annealing temperature is 100-400 ℃.
3. The method of fabricating a bonded wafer structure according to claim 2, wherein: the cleaning in the step A is an RCA wet chemical cleaning method, wherein the cleaning liquid adopted by the RCA wet chemical cleaning method comprises a mixed solution of an organic solvent, sulfuric acid and hydrogen peroxide and a mixed solution of ammonia water, hydrogen peroxide and deionized water; in a mixed solution of sulfuric acid and hydrogen peroxide, the concentration of the sulfuric acid is 96%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the sulfuric acid to the hydrogen peroxide is 4:1; in the mixed solution of the ammonia water, the hydrogen peroxide and the deionized water, the concentration of the ammonia water is 29%, the concentration of the hydrogen peroxide is 30%, and the volume ratio of the three liquids is as follows: ammonia water, hydrogen peroxide and deionized water in the ratio of 1:1:5; the cleaning method comprises the following steps: removing oil stains on the surfaces of the first wafer and the second wafer by adopting the organic solvent; ultrasonically cleaning particles adsorbed on the surfaces of the first wafer and the second wafer; heating the mixed solution of sulfuric acid and hydrogen peroxide to 95 ℃, soaking the first wafer and the second wafer for 20 minutes, and rapidly washing the soaked first wafer and second wafer with deionized water to remove metal ions; heating the mixed solution of ammonia water, hydrogen peroxide and deionized water to 80 ℃, soaking the first wafer and the second wafer for 15 minutes, keeping the temperature of the mixed solution of ammonia water, hydrogen peroxide and deionized water unchanged in the soaking process, and then rapidly washing the soaked first wafer and second wafer by using deionized water.
4. The method of fabricating a bonded wafer structure according to claim 2, wherein: and (C) drying in the step A, namely drying by adopting nitrogen.
5. The method of fabricating a bonded wafer structure according to claim 2, wherein: and (C) scrubbing and/or polishing the first wafer and the second wafer after cleaning.
6. The method of claim 1, wherein the second step comprises depositing aluminum metal having a thickness of 20nm by one of an organic metal chemical vapor deposition method, a plasma-enhanced chemical vapor deposition method, an atomic layer deposition method, sputtering, an electron beam deposition method, and a laser pulse deposition method.
7. The method of fabricating a bonded wafer structure according to claim 2, wherein: the gas channels in the step E are groove-shaped equidistant gas channels.
8. The method of fabricating a bonded wafer structure according to claim 2, wherein: the etching in the step E adopts mixed gas of boron trichloride and chlorine to etch; the etching is performed in a cavity at the temperature of 60 ℃, and the etching time is 60-80 s.
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| CN109243989B (en) * | 2018-09-03 | 2020-01-17 | 合肥工业大学 | Silicon-silicon low-temperature bonding method based on graphene slurry |
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| CN110634797A (en) * | 2019-09-30 | 2019-12-31 | 闽南师范大学 | Method for eliminating Ge/Si bonding interface bubbles by graphical scribing |
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Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10233352A (en) * | 1996-12-18 | 1998-09-02 | Canon Inc | Manufacture of semiconductor member and semiconductor member |
| JP2000226270A (en) * | 2000-01-01 | 2000-08-15 | Ibiden Co Ltd | Aluminum nitride substrate |
| JP2001313381A (en) * | 2000-04-28 | 2001-11-09 | Matsushita Electric Ind Co Ltd | Semiconductor wafer and semiconductor device using the same, and method of manufacturing the semiconductor device |
| CN1379436A (en) * | 2001-03-30 | 2002-11-13 | 惠普公司 | Substrate linkage using selenylation reaction |
| CN102479913A (en) * | 2010-11-29 | 2012-05-30 | 上海蓝宝光电材料有限公司 | High-efficiency high-voltage vertical through hole bonding type light emitting diode (LED) chip and manufacture method thereof |
| CN103079744A (en) * | 2010-08-31 | 2013-05-01 | 日产自动车株式会社 | Method for bonding aluminum-based metals |
| WO2014002577A1 (en) * | 2012-06-28 | 2014-01-03 | 株式会社豊田自動織機 | Method for producing semiconductor substrate |
| KR101585082B1 (en) * | 2014-09-24 | 2016-01-14 | 한국생산기술연구원 | The heating unit and method of fabricating the same and the ESC of controllable temperature using thereof |
| JP2017152425A (en) * | 2016-02-22 | 2017-08-31 | 日本碍子株式会社 | Substrate bonding method using metal zinc film |
| CN207441658U (en) * | 2017-10-30 | 2018-06-01 | 桂林电子科技大学 | A kind of structure for being bonded wafer |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI309074B (en) * | 2002-02-07 | 2009-04-21 | Advanced Epitaxy Technology | Method of forming semiconductor device |
| TW200707799A (en) * | 2005-04-21 | 2007-02-16 | Aonex Technologies Inc | Bonded intermediate substrate and method of making same |
| US20060284167A1 (en) * | 2005-06-17 | 2006-12-21 | Godfrey Augustine | Multilayered substrate obtained via wafer bonding for power applications |
| US20100089978A1 (en) * | 2008-06-11 | 2010-04-15 | Suss Microtec Inc | Method and apparatus for wafer bonding |
| FR3001225B1 (en) * | 2013-01-22 | 2016-01-22 | Commissariat Energie Atomique | METHOD FOR MANUFACTURING DIRECT COLLAGE STRUCTURE |
-
2017
- 2017-10-30 CN CN201711030930.1A patent/CN107742606B/en active Active
Patent Citations (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10233352A (en) * | 1996-12-18 | 1998-09-02 | Canon Inc | Manufacture of semiconductor member and semiconductor member |
| JP2000226270A (en) * | 2000-01-01 | 2000-08-15 | Ibiden Co Ltd | Aluminum nitride substrate |
| JP2001313381A (en) * | 2000-04-28 | 2001-11-09 | Matsushita Electric Ind Co Ltd | Semiconductor wafer and semiconductor device using the same, and method of manufacturing the semiconductor device |
| CN1379436A (en) * | 2001-03-30 | 2002-11-13 | 惠普公司 | Substrate linkage using selenylation reaction |
| CN103079744A (en) * | 2010-08-31 | 2013-05-01 | 日产自动车株式会社 | Method for bonding aluminum-based metals |
| CN102479913A (en) * | 2010-11-29 | 2012-05-30 | 上海蓝宝光电材料有限公司 | High-efficiency high-voltage vertical through hole bonding type light emitting diode (LED) chip and manufacture method thereof |
| WO2014002577A1 (en) * | 2012-06-28 | 2014-01-03 | 株式会社豊田自動織機 | Method for producing semiconductor substrate |
| KR101585082B1 (en) * | 2014-09-24 | 2016-01-14 | 한국생산기술연구원 | The heating unit and method of fabricating the same and the ESC of controllable temperature using thereof |
| JP2017152425A (en) * | 2016-02-22 | 2017-08-31 | 日本碍子株式会社 | Substrate bonding method using metal zinc film |
| CN207441658U (en) * | 2017-10-30 | 2018-06-01 | 桂林电子科技大学 | A kind of structure for being bonded wafer |
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