CN113061854A - Method for preparing getter by utilizing AMAT PVD cavity and thin film getter thereof - Google Patents
Method for preparing getter by utilizing AMAT PVD cavity and thin film getter thereof Download PDFInfo
- Publication number
- CN113061854A CN113061854A CN202110294941.0A CN202110294941A CN113061854A CN 113061854 A CN113061854 A CN 113061854A CN 202110294941 A CN202110294941 A CN 202110294941A CN 113061854 A CN113061854 A CN 113061854A
- Authority
- CN
- China
- Prior art keywords
- getter
- silicon wafer
- amat
- pvd
- preparing
- 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.)
- Pending
Links
- 101100107923 Vitis labrusca AMAT gene Proteins 0.000 title claims abstract description 21
- 238000000034 method Methods 0.000 title claims abstract description 21
- 239000010409 thin film Substances 0.000 title claims abstract description 9
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 29
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 29
- 239000010703 silicon Substances 0.000 claims abstract description 29
- 239000010408 film Substances 0.000 claims abstract description 15
- KFZMGEQAYNKOFK-UHFFFAOYSA-N Isopropanol Chemical compound CC(C)O KFZMGEQAYNKOFK-UHFFFAOYSA-N 0.000 claims abstract description 14
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 claims abstract description 8
- 238000004140 cleaning Methods 0.000 claims abstract description 8
- 238000001035 drying Methods 0.000 claims abstract description 8
- 238000005530 etching Methods 0.000 claims abstract description 8
- 238000010438 heat treatment Methods 0.000 claims abstract description 8
- 230000008569 process Effects 0.000 claims abstract description 8
- 229910021642 ultra pure water Inorganic materials 0.000 claims abstract description 8
- 239000012498 ultrapure water Substances 0.000 claims abstract description 8
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims abstract description 7
- 238000002791 soaking Methods 0.000 claims abstract description 7
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 4
- 229910045601 alloy Inorganic materials 0.000 claims abstract description 4
- 239000000956 alloy Substances 0.000 claims abstract description 4
- 230000007797 corrosion Effects 0.000 claims abstract description 4
- 238000005260 corrosion Methods 0.000 claims abstract description 4
- 238000002360 preparation method Methods 0.000 claims abstract description 4
- 239000013077 target material Substances 0.000 claims abstract description 4
- 238000004506 ultrasonic cleaning Methods 0.000 claims abstract description 4
- 230000009471 action Effects 0.000 claims description 7
- 239000002184 metal Substances 0.000 claims description 6
- 230000005684 electric field Effects 0.000 claims description 4
- 230000015572 biosynthetic process Effects 0.000 claims description 3
- 230000003116 impacting effect Effects 0.000 claims description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 7
- 238000005240 physical vapour deposition Methods 0.000 description 20
- 239000007789 gas Substances 0.000 description 3
- 229910000986 non-evaporable getter Inorganic materials 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 230000003213 activating effect Effects 0.000 description 1
- 230000004913 activation Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000000151 deposition Methods 0.000 description 1
- 230000008021 deposition Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000001755 magnetron sputter deposition Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/22—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the process of coating
- C23C14/34—Sputtering
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/28—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties
- B01J20/28014—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof characterised by their form or physical properties characterised by their form
- B01J20/28033—Membrane, sheet, cloth, pad, lamellar or mat
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
- B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
- B01J20/00—Solid sorbent compositions or filter aid compositions; Sorbents for chromatography; Processes for preparing, regenerating or reactivating thereof
- B01J20/30—Processes for preparing, regenerating, or reactivating
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C14/00—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material
- C23C14/06—Coating by vacuum evaporation, by sputtering or by ion implantation of the coating forming material characterised by the coating material
- C23C14/14—Metallic material, boron or silicon
- C23C14/16—Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon
- C23C14/165—Metallic material, boron or silicon on metallic substrates or on substrates of boron or silicon by cathodic sputtering
Landscapes
- Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Analytical Chemistry (AREA)
- Drying Of Solid Materials (AREA)
Abstract
The invention relates to the technical field of getter preparation, in particular to a method for preparing a getter by utilizing an AMAT PVD cavity and a film getter thereof, which comprises the following steps: step 1, preparing an etching solution for cleaning a silicon wafer, wherein the etching solution is mainly prepared from a NAOH solution and an isopropanol solution for later use; step 2, sequentially putting the silicon wafer into acetone, alcohol and ultrapure water, and sequentially carrying out ultrasonic cleaning for later use; step 3, soaking the silicon wafer cleaned in the step 2 in the prepared corrosion solution in the step 1, and heating for 50min at the temperature of 85-95 ℃; step 4, ultrasonically cleaning the silicon wafer soaked in the step 3 by using ultrapure water, and then drying the silicon wafer by using a drying machine; step 5, putting the silicon wafer cleaned and dried in the step 4 into PVD equipment for process treatment, wherein the alloy target material component installed in a process cavity of the PVD equipment is ZR-CO-RE; the feasibility of producing the film getter by using AMAT PVD equipment is realized; thereby addressing the need for mass production of thin film getters.
Description
Technical Field
The invention relates to the technical field of getter preparation, in particular to a method for preparing a getter by utilizing an AMAT PVD cavity and a film getter thereof.
Background
Getters refer to the generic term for agents or devices that effectively sorb certain gas molecule(s) to obtain or maintain a vacuum, purify gases, and the like.
With the development of scientific technology, vacuum environment required by many scientific research and production fields is higher and higher. The getters are produced by transportation, and are mainly divided into three types: one is an evaporable getter, the second is a non-evaporable getter, and the third is a composite getter (i.e. with evaporable and non-evaporable getters).
The evaporable getter is required to evaporate the getter material during operation and condense it on a metal support (generally made of a metal tube or a metal disk) when cooled. The non-evaporable getter can absorb a large amount of impure gas only by heating and activating. On the premise of small size, excellent air suction performance and low activation temperature, the film getter is a hot point of research in the industry, and the deposition of the film getter on the inner wall of a vacuum device by adopting magnetron sputtering is rapidly developed.
Disclosure of Invention
Aiming at the defects of the prior art, the invention provides a method for preparing a getter by utilizing an AMAT PVD cavity and a film getter thereof, thereby realizing the feasibility of producing the film getter by using AMAT PVD equipment; AMAT PVD is an efficient and stable apparatus, thereby addressing the need for mass production of thin film getters.
The invention is realized by the following technical scheme: a method of making a getter using an AMAT PVD chamber, comprising the steps of:
step 1, preparing an etching solution for cleaning a silicon wafer, wherein the etching solution is mainly prepared from a NAOH solution and an isopropanol solution for later use;
step 2, sequentially putting the silicon wafer into acetone, alcohol and ultrapure water, and sequentially carrying out ultrasonic cleaning for later use;
step 3, soaking the silicon wafer cleaned in the step 2 in the prepared corrosion solution in the step 1, and heating for 50min at the temperature of 85-95 ℃;
step 4, ultrasonically cleaning the silicon wafer soaked in the step 3 by using ultrapure water, and then drying the silicon wafer by using a drying machine;
and 5, putting the silicon wafer cleaned and dried in the step 4 into PVD equipment for process treatment, wherein the alloy target material component installed in a process cavity of the PVD equipment is ZR-CO-RE.
Preferably, the content of the NAOH and isopropanol solution in step 1 is 3wt.% and 5wt.%, respectively.
Preferably, the temperature for soaking and heating the silicon wafer in the step 3 is 90 ℃.
Preferably, when the silicon wafer is processed in the PVD equipment in the step 5, the DC POWER SUPPLY is connected to the TARGET, and a negative voltage is applied to the DC POWER SUPPLY to form PLASMA (AR) between the TARGER and the HEAT+）。
Preferably, the AR+Striking TARGET under the action of an electric field, wherein AR+And impacting TARGET in a spiral mode under the action of a magnetic field to separate metal atoms from TARGET so as to realize film formation and finish the preparation of the film getter.
The invention also comprises the following technical scheme to realize: the thin-film getter is prepared by the method for preparing the getter by utilizing the AMAT PVD cavity.
The invention has the beneficial effects that: the feasibility of producing the film getter by using AMAT PVD equipment is realized; AMAT PVD is an efficient and stable apparatus, thereby addressing the need for mass production of thin film getters.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.
FIG. 1 is a schematic diagram of the working principle of the PVD chamber of the invention;
FIG. 2 is a schematic diagram of the working principle of the present invention in which AR + strikes TARGET under the action of an electric field.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1:
a method of making a getter using an AMAT PVD chamber, comprising the steps of:
step 1, preparing an etching solution for cleaning a silicon wafer, wherein the etching solution is mainly prepared from a NAOH solution and an isopropanol solution for later use;
step 2, sequentially putting the silicon wafer into acetone, alcohol and ultrapure water, and sequentially carrying out ultrasonic cleaning for later use;
step 3, soaking the silicon wafer cleaned in the step 2 in the prepared corrosion solution in the step 1, and heating for 50min at the temperature of 85-95 ℃;
step 4, ultrasonically cleaning the silicon wafer soaked in the step 3 by using ultrapure water, and then drying the silicon wafer by using a drying machine;
and 5, putting the silicon wafer cleaned and dried in the step 4 into PVD equipment for process treatment, wherein the alloy target material component installed in a process cavity of the PVD equipment is ZR-CO-RE.
Specifically, the content of the NAOH and isopropanol solution in the step 1 is 3wt.% and 5wt.%, respectively.
Specifically, the temperature for soaking and heating the silicon wafer in the step 3 is 90 ℃.
Specifically, referring to fig. 1, when the silicon wafer is processed in the PVD apparatus in step 5, the DC POWER SUPPLY is connected to the TARGET, and a negative voltage is applied to the TARGET to form a PLASMA (AR) between the TARGET and the HEATER+）。
Specifically, referring to FIG. 2, the AR+Striking TARGET under the action of an electric field, wherein AR+Impacting TARGET in a spiral mode under the action of a magnetic field to separate metal atoms from TARGET so as to realize film formation and finish the film getterAnd (4) preparing.
The invention also comprises the following technical scheme to realize: the thin-film getter is prepared by the method for preparing the getter by utilizing the AMAT PVD cavity. The feasibility of producing the film getter by using AMAT PVD equipment is realized; AMAT PVD is an efficient and stable apparatus, thereby addressing the need for mass production of thin film getters.
The above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.
Claims (6)
1. A method for preparing a getter by utilizing an AMAT PVD cavity is characterized by comprising the following steps:
step 1, preparing an etching solution for cleaning a silicon wafer, wherein the etching solution is mainly prepared from a NAOH solution and an isopropanol solution for later use;
step 2, sequentially putting the silicon wafer into acetone, alcohol and ultrapure water, and sequentially carrying out ultrasonic cleaning for later use;
step 3, soaking the silicon wafer cleaned in the step 2 in the prepared corrosion solution in the step 1, and heating for 50min at the temperature of 85-95 ℃;
step 4, ultrasonically cleaning the silicon wafer soaked in the step 3 by using ultrapure water, and then drying the silicon wafer by using a drying machine;
and 5, putting the silicon wafer cleaned and dried in the step 4 into PVD equipment for process treatment, wherein the alloy target material component installed in a process cavity of the PVD equipment is ZR-CO-RE.
2. The method for preparing getter using AMAT PVD chamber as claimed in claim 1, wherein the NAOH and isopropanol solution content in step 1 is 3wt.% and 5wt.%, respectively.
3. The method for preparing the getter by using the AMAT PVD chamber as claimed in claim 1, wherein the temperature for soaking and heating the silicon wafer in the step 3 is 90 ℃.
4. The method as claimed in claim 1, wherein the step 5 is performed by a PVD tool with a DC POWER SUPPLY connected to the TARGET, and a negative voltage is applied to the TARGET to form a PLASMA (AR) between the TARGER and the HEADER+）。
5. The method of claim 4, wherein the AR is prepared by using AMAT PVD chamber with getter+Striking TARGET under the action of an electric field, wherein AR+And impacting TARGET in a spiral mode under the action of a magnetic field to separate metal atoms from TARGET so as to realize film formation and finish the preparation of the film getter.
6. A thin film getter comprising a getter according to any of claims 1 to 5, prepared by a method for preparing a getter using an AMAT PVD chamber.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110294941.0A CN113061854A (en) | 2021-03-19 | 2021-03-19 | Method for preparing getter by utilizing AMAT PVD cavity and thin film getter thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110294941.0A CN113061854A (en) | 2021-03-19 | 2021-03-19 | Method for preparing getter by utilizing AMAT PVD cavity and thin film getter thereof |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113061854A true CN113061854A (en) | 2021-07-02 |
Family
ID=76562319
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110294941.0A Pending CN113061854A (en) | 2021-03-19 | 2021-03-19 | Method for preparing getter by utilizing AMAT PVD cavity and thin film getter thereof |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113061854A (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005047558A2 (en) * | 2003-11-14 | 2005-05-26 | Saes Getters S.P.A. | Process for manufacturing devices which require a non evaporable getter material for their working |
| CN103849835A (en) * | 2012-11-29 | 2014-06-11 | 北京有色金属研究总院 | Zr-Co-Re thin film getter provided with protection layer, and preparation method thereof |
| CN107400854A (en) * | 2017-07-17 | 2017-11-28 | 云南师范大学 | Non-evaporation type low temp activation Zr base Fe Getter Films Prepared and preparation method thereof |
| CN109136867A (en) * | 2018-08-09 | 2019-01-04 | 李志平 | A kind of preparation method of Fe Getter Films Prepared |
| CN109680249A (en) * | 2019-01-25 | 2019-04-26 | 苏州大学 | Non-evaporable film getter and preparation method thereof |
-
2021
- 2021-03-19 CN CN202110294941.0A patent/CN113061854A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2005047558A2 (en) * | 2003-11-14 | 2005-05-26 | Saes Getters S.P.A. | Process for manufacturing devices which require a non evaporable getter material for their working |
| CN103849835A (en) * | 2012-11-29 | 2014-06-11 | 北京有色金属研究总院 | Zr-Co-Re thin film getter provided with protection layer, and preparation method thereof |
| CN107400854A (en) * | 2017-07-17 | 2017-11-28 | 云南师范大学 | Non-evaporation type low temp activation Zr base Fe Getter Films Prepared and preparation method thereof |
| CN109136867A (en) * | 2018-08-09 | 2019-01-04 | 李志平 | A kind of preparation method of Fe Getter Films Prepared |
| CN109680249A (en) * | 2019-01-25 | 2019-04-26 | 苏州大学 | Non-evaporable film getter and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 易丹青等: "《金属硅化物》", 30 September 2012, 冶金工业出版社 * |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108531877B (en) | TiZrVHf quaternary getter film | |
| CN105177493B (en) | A kind of surface of hot working die arc-plasma auxiliary low pressure nitriding method | |
| CN105340050A (en) | Ion milling device and processing method using the ion milling device | |
| CN113061854A (en) | Method for preparing getter by utilizing AMAT PVD cavity and thin film getter thereof | |
| CN108546929A (en) | A kind of method, the substrate with film and its application preparing titanium nitride nano film in substrate surface | |
| CN201793721U (en) | Vacuum electronic gun coating machine | |
| CN103898458A (en) | Method for preparing silicon nano crystal film by adopting spiral wave plasma sputtering technology | |
| US20120237790A1 (en) | Housing and method for making the same | |
| US8568907B2 (en) | Housing and method for making the same | |
| JP2007063615A (en) | Method for forming lithium or lithium alloy thin film | |
| US2808980A (en) | Electrical vacuum pump | |
| US11365475B2 (en) | Physical vapor deposition chamber cleaning processes | |
| CN102242339A (en) | Preparation method of oxygen-stabilized yttrium fluoride film | |
| CN113345979A (en) | Quick resetting method for vacuum machine table | |
| CN102732889B (en) | Method and apparatus for removing metal on wafer clamp | |
| CN102347182A (en) | Method for manufacturing tantalum heat shield of multiple-beam TWT (travelling wave tube) cathode | |
| US8568905B2 (en) | Housing and method for making the same | |
| CN211858576U (en) | Heating system for electron gun of exposure machine | |
| CN112919822A (en) | Graphene glass preparation method based on etching auxiliary mechanism | |
| US8597804B2 (en) | Housing and method for making the same | |
| US8597782B2 (en) | Housing and method for making the same | |
| CN102080208A (en) | Ti-Ni-Hf-Cu quaternary high-temperature shape memory alloy film and preparation method thereof | |
| US8568904B2 (en) | Housing and method for making the same | |
| US8568906B2 (en) | Housing and method for making the same | |
| CN210012898U (en) | Vacuumizing equipment and coating equipment |
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 | ||
| TA01 | Transfer of patent application right | ||
| TA01 | Transfer of patent application right |
Effective date of registration: 20210824 Address after: Room 302-22, building F, Wuxi Information Industry Technology Park, 21 Changjiang Road, Xinwu District, Wuxi City, Jiangsu Province, 214000 Applicant after: Wuxi Shangji Semiconductor Technology Co.,Ltd. Address before: Part 25, 3rd floor, 39 Jiatai Road, China (Shanghai) pilot Free Trade Zone, Pudong New Area, Shanghai Applicant before: Shanghai Songshang International Trade Co.,Ltd. |
|
| RJ01 | Rejection of invention patent application after publication | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20210702 |