CN113862636A - 一种基于平整二维结构衬底的石墨烯超材料cvd制备方法 - Google Patents
一种基于平整二维结构衬底的石墨烯超材料cvd制备方法 Download PDFInfo
- Publication number
- CN113862636A CN113862636A CN202110922973.0A CN202110922973A CN113862636A CN 113862636 A CN113862636 A CN 113862636A CN 202110922973 A CN202110922973 A CN 202110922973A CN 113862636 A CN113862636 A CN 113862636A
- Authority
- CN
- China
- Prior art keywords
- graphene
- metamaterial
- metal substrate
- cvd
- dimensional structure
- 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
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 title claims abstract description 67
- 229910021389 graphene Inorganic materials 0.000 title claims abstract description 64
- 239000000758 substrate Substances 0.000 title claims abstract description 44
- 238000002360 preparation method Methods 0.000 title claims abstract description 14
- 238000005229 chemical vapour deposition Methods 0.000 claims abstract description 28
- 239000002184 metal Substances 0.000 claims abstract description 28
- 229910052751 metal Inorganic materials 0.000 claims abstract description 28
- 239000000463 material Substances 0.000 claims abstract description 23
- 238000005530 etching Methods 0.000 claims abstract description 16
- 239000000945 filler Substances 0.000 claims abstract description 15
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000005498 polishing Methods 0.000 claims abstract description 9
- 230000007246 mechanism Effects 0.000 claims abstract description 4
- 230000009286 beneficial effect Effects 0.000 claims abstract 2
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 4
- 230000003287 optical effect Effects 0.000 claims description 3
- 229920002120 photoresistant polymer Polymers 0.000 claims description 3
- 230000008569 process Effects 0.000 claims description 3
- 239000011347 resin Substances 0.000 claims description 3
- 229920005989 resin Polymers 0.000 claims description 3
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 claims description 2
- 229910052802 copper Inorganic materials 0.000 claims description 2
- 239000010949 copper Substances 0.000 claims description 2
- 229910052759 nickel Inorganic materials 0.000 claims description 2
- 238000000151 deposition Methods 0.000 abstract description 8
- 230000008021 deposition Effects 0.000 abstract description 6
- 230000008901 benefit Effects 0.000 abstract description 4
- 238000010894 electron beam technology Methods 0.000 description 3
- 230000002349 favourable effect Effects 0.000 description 3
- 238000001259 photo etching Methods 0.000 description 3
- 230000007547 defect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 2
- 238000004026 adhesive bonding Methods 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000003486 chemical etching Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 238000012377 drug delivery Methods 0.000 description 1
- 230000002427 irreversible effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 239000002356 single layer Substances 0.000 description 1
- 239000000126 substance Substances 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
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/22—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the deposition of inorganic material, other than metallic material
- C23C16/26—Deposition of carbon only
-
- 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
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/02—Pretreatment of the material to be coated
- C23C16/0227—Pretreatment of the material to be coated by cleaning or etching
-
- 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
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/02—Pretreatment of the material to be coated
- C23C16/0254—Physical treatment to alter the texture of the surface, e.g. scratching or polishing
-
- 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
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/04—Coating on selected surface areas, e.g. using masks
- C23C16/042—Coating on selected surface areas, e.g. using masks using masks
-
- 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
- C23C16/00—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes
- C23C16/44—Chemical coating by decomposition of gaseous compounds, without leaving reaction products of surface material in the coating, i.e. chemical vapour deposition [CVD] processes characterised by the method of coating
Landscapes
- Chemical & Material Sciences (AREA)
- General Chemical & Material Sciences (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Inorganic Chemistry (AREA)
- Carbon And Carbon Compounds (AREA)
Abstract
本发明公开了一种基于平整二维结构衬底的石墨烯超材料CVD制备方法:首先,根据需求设计石墨烯超材料二维结构图案,并生成工程文档;接着,根据所设计图案对所选金属衬底进行刻蚀,注入填充剂填充刻蚀部分,防止石墨烯生长至衬底侧面;然后,对金属衬底进行打磨,磨掉多余填充剂露出金属衬底材料,并使表面平整;最后,运用CVD法生成具备二维微纳机构的石墨烯超材料。本发明具有较低的成本,且不易对石墨烯材料本身造成破坏,确保石墨烯材料完整性,同时,创造了平整的衬底表面,更有利于石墨烯结构沉积。
Description
技术领域
本发明属于新材料技术领域,具体涉及一种基于平整二维结构沉底的石墨烯超材料CVD制备方法。
背景技术
超材料指的是一类具有特殊性质的人造材料,这些材料是自然界没有的。它们拥有一些特别的性质,比如让光、电磁波改变它们的通常性质,而这样的效果是传统材料无法实现的。超材料的成分上没有什么特别之处,它们的奇特性质源于其精密的几何结构以及尺寸大小。其中的微结构,大小尺度小于它作用的波长,因此得以对波施加影响。
石墨烯(Graphene)是一种以sp2杂化连接的碳原子紧密堆积成单层二维蜂窝状晶格结构的新材料。石墨烯具有优异的光学、电学、力学特性,在材料学、微纳加工、能源、生物医学和药物传递等方面具有重要的应用前景。
但是,制备石墨烯超材料需要制造具有特定二位结构的石墨烯,但石墨烯化学性质极为稳定化学刻蚀较困难,现有石墨烯二维材料加工发放主要有物理刻蚀方法、CVD沉积法,物理刻蚀方法是运用激光、电子束等高能射线进行刻蚀,CVD法是通过光刻技术在基板表面制备掩膜,然后进行化学气相沉积,最后清洗掩膜,得到需要的石墨烯结构。
然而,运用激光、电子束等高能射线进行刻蚀虽然精度高,但是速度较慢且成本高昂,还会对石墨烯材料造成不可逆损伤,不利于应用至大规模生产。运用掩膜的CVD化学气相沉积方法虽然成本较低,但由于掩膜带来的表面不平整,在一定速度气体流动下不利于石墨烯沉积,掩膜边缘石墨烯结构容易产生缺陷。
发明目的
本发明的目的是为了解决现有石墨烯超材料加工刻蚀复杂、成本高,易损伤的问题,旨在提供一种基于平整二维结构衬底的石墨烯超材料CVD制备方法,在保留CVD低成本生成石墨烯优点的同时,提高石墨烯超材料二维结构制备的品质,具有更加可靠、便捷、高精度的特点。
发明内容
本发明提供了一种可自由控制形态的石墨烯超材料CVD制备方法,包括以下步骤:
步骤1:根据需求设计石墨烯超材料二维结构图案,并生成工程文档;
步骤2:根据所设计的石墨烯超材料二维结构图案对所选金属衬底进行刻蚀,注入填充剂填充刻蚀部分,防止石墨烯生长至衬底侧面;
步骤3:对步骤2中所述金属衬底进行打磨,磨掉多余填充剂露出所述金属衬底材料,并使其表面平整;
步骤4::运用CVD法生成具备二维微纳机构的石墨烯超材料。
优选地,所述石墨烯超材料二维结构图案为根据应用场景设计的具备光学、电磁特性的超材料图案。
优选地,步骤2中所述刻蚀采用PCB工艺。
优选地,所述金属衬底为CVD法生成石墨烯时所用衬底,其材质包括铜、镍。
优选地,所述填充剂包括不利于CVD石墨烯生长的树脂、光刻胶材料,其被打磨成平整表面,以防止石墨烯生长至金属衬底刻蚀区域的侧面。
附图说明
图1是不同结构衬底CVD法石墨烯超材料沉积状况示意图。
附图标记:
1-CVD法生成的石墨烯超材料;
2-为金属衬底;
3-不利于石墨烯沉积的填充剂。
具体实施方式
以下结合附图详细阐述本发明的具体实施方式,本领域技术人员应当明白,此处的实施方式仅是对本发明的示例性说明,而不应被视为对本发明的限定,任何不脱离本发明主旨的等效替代或变动都落入本发明的范围。
本发明提供了一种可自由控制形态的石墨烯超材料CVD制备方法,包括以下步骤:
(1)根据需求设计石墨烯超材料二维结构图案,并生成工程文档。
(2)运用传统pcb加工工艺,依据设计图案对所选金属衬底进行刻蚀。
(3)注入填充剂填充被刻蚀部分。
(4)对加注填充剂的金属衬底进行打磨,磨掉多余填充剂露出金属衬底材料,并使表面平整。
(5)运用CVD法生成具备二维微纳机构的石墨烯超材料。
(6)去除衬底及填充剂,得到具备二维微纳结构的石墨烯超材料。
图1是不同结构衬底CVD法石墨烯超材料沉积状况示意图,其中,(1)是CVD法生成的石墨烯超材料;(2)为金属衬底;(3)是不利于石墨烯沉积的填充剂。如图所示,一为本发明所述的具备微纳尺度二维结构的平整金属衬底CVD法生成石墨烯超材料,石墨烯生成状况良好;二为未加注填充剂的金属衬底,石墨烯在刻蚀槽垂直的壁上也存在生成,引入不可控变量,不利于石墨烯超材料的制备;三为不对金属衬底进行刻蚀,直接通过光刻技术在衬底上制备掩膜,然后进行CVD气相沉积,因气相沉积通入甲烷气体具备一定流速,因此,在掩膜边缘石墨烯生成会收到影响,形成缺陷。
与现有技术相比,本发明具有以下优点:
1、通过对金属衬底的刻蚀、涂胶和打磨,创造出了具备微纳尺度二位结构的平整金属衬底,可高精度生长所需结构石墨烯超材料。
2、与激光,电子束等物理刻蚀方法比较,本发明具有较低的成本,且不易对石墨烯材料本身造成破坏,确保石墨烯材料完整性。
3、与金属衬底直接光刻掩膜进行不同形态石墨烯制备的方法相比,本发明创造了平整的衬底表面,更有利于石墨烯结构沉积。具备良好的应用前景。
Claims (5)
1.一种可自由控制形态的石墨烯超材料CVD制备方法,其特征在于,包括以下步骤:
步骤1:根据需求设计石墨烯超材料二维结构图案,并生成工程文档;
步骤2:根据所设计的石墨烯超材料二维结构图案对所选金属衬底进行刻蚀,注入填充剂填充刻蚀部分,防止石墨烯生长至衬底侧面;
步骤3:对步骤2中所述金属衬底进行打磨,磨掉多余填充剂露出所述金属衬底材料,并使其表面平整;
步骤4::运用CVD法生成具备二维微纳机构的石墨烯超材料。
2.根据权利要求1所述的一种可自由控制形态的石墨烯超材料CVD制备方法,其特征在于,所述石墨烯超材料二维结构图案为根据应用场景设计的具备光学、电磁特性的超材料图案。
3.根据权利要求1所述的一种可自由控制形态的石墨烯超材料CVD制备方法,其特征在于,步骤2中所述刻蚀采用PCB工艺。
4.根据权利要求1所述的一种可自由控制形态的石墨烯超材料CVD制备方法,其特征在于,所述金属衬底为CVD法生成石墨烯时所用衬底,其材质包括铜、镍。
5.根据权利要求1所述的一种可自由控制形态的石墨烯超材料CVD制备方法,其特征在于,所述填充剂包括不利于CVD石墨烯生长的树脂、光刻胶材料,其被打磨成平整表面,以防止石墨烯生长至金属衬底刻蚀区域的侧面。
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110922973.0A CN113862636B (zh) | 2021-08-12 | 2021-08-12 | 一种可自由控制形态的石墨烯超材料cvd制备方法 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202110922973.0A CN113862636B (zh) | 2021-08-12 | 2021-08-12 | 一种可自由控制形态的石墨烯超材料cvd制备方法 |
Publications (2)
Publication Number | Publication Date |
---|---|
CN113862636A true CN113862636A (zh) | 2021-12-31 |
CN113862636B CN113862636B (zh) | 2023-12-26 |
Family
ID=78990474
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202110922973.0A Active CN113862636B (zh) | 2021-08-12 | 2021-08-12 | 一种可自由控制形态的石墨烯超材料cvd制备方法 |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN113862636B (zh) |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150060281A1 (en) * | 2013-08-27 | 2015-03-05 | Tokyo Institute Of Technology | Method for manufacturing metamaterial |
CN108507685A (zh) * | 2018-03-13 | 2018-09-07 | 烟台睿创微纳技术股份有限公司 | 一种石墨烯探测器及其制备方法 |
US20190341256A1 (en) * | 2018-05-07 | 2019-11-07 | Lam Research Corporation | Selective deposition of etch-stop layer for enhanced patterning |
CN110515224A (zh) * | 2019-09-04 | 2019-11-29 | 哈尔滨理工大学 | 一种双带可灵活选择性调控的石墨烯-金属槽超材料太赫兹慢光器件 |
CN111273462A (zh) * | 2020-03-02 | 2020-06-12 | 江西师范大学 | 光学腔与石墨烯复合结构吸波器 |
-
2021
- 2021-08-12 CN CN202110922973.0A patent/CN113862636B/zh active Active
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20150060281A1 (en) * | 2013-08-27 | 2015-03-05 | Tokyo Institute Of Technology | Method for manufacturing metamaterial |
CN108507685A (zh) * | 2018-03-13 | 2018-09-07 | 烟台睿创微纳技术股份有限公司 | 一种石墨烯探测器及其制备方法 |
US20190341256A1 (en) * | 2018-05-07 | 2019-11-07 | Lam Research Corporation | Selective deposition of etch-stop layer for enhanced patterning |
CN110515224A (zh) * | 2019-09-04 | 2019-11-29 | 哈尔滨理工大学 | 一种双带可灵活选择性调控的石墨烯-金属槽超材料太赫兹慢光器件 |
CN111273462A (zh) * | 2020-03-02 | 2020-06-12 | 江西师范大学 | 光学腔与石墨烯复合结构吸波器 |
Also Published As
Publication number | Publication date |
---|---|
CN113862636B (zh) | 2023-12-26 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN107419329B (zh) | 单晶金刚石表面原位n型半导体化全碳结构的制备方法 | |
CN110938864B (zh) | 一种高效调控cvd单晶金刚石局部区域位错密度的方法 | |
CN104975343A (zh) | 利用氢等离子体多次刻蚀/退火循环工艺提高金刚石籽晶质量的方法 | |
CN103199161B (zh) | 一种在GaP表面制备锥状结构的方法 | |
CN108766857B (zh) | 一种GaAs纳米光学共振结构光电阴极电子源及其制备方法 | |
JPH0676666B2 (ja) | 炭素膜作製方法 | |
CN114411250B (zh) | 一种mpcvd单晶金刚石拼接生长方法 | |
CN107841711A (zh) | 一种减小光学窗口用四面体非晶碳膜残余应力的方法 | |
CN106384770A (zh) | 纳米/微米复合图形化蓝宝石衬底及其制备方法 | |
CN113862636A (zh) | 一种基于平整二维结构衬底的石墨烯超材料cvd制备方法 | |
WO2019006799A1 (zh) | 纳米线栅偏光片的制作方法 | |
CN112479155B (zh) | 一种增强二硫化锡纳米片非线性光学性能的方法 | |
KR101127742B1 (ko) | 레이저를 이용한 그래핀 제조방법, 이에 의하여 제조된 그래핀, 이를 위한 제조장치 | |
CN111005065B (zh) | 一种金刚石膜的等离子体电弧沉积装置与方法 | |
CN101378016B (zh) | 利用准分子激光退火制作SiGe或Ge量子点的方法 | |
CN110148884B (zh) | 一种垂直腔面发射激光器及其制备方法 | |
CN101823684A (zh) | 一种仿蝴蝶磷翅分级多层非对称微纳结构的制备方法 | |
CN110886019A (zh) | 一种基于碱金属溶液催化的二硫化钼制备方法 | |
CN113636545A (zh) | 一种基于边缘拓扑优化的石墨烯超材料改性方法 | |
CN1310270C (zh) | 一种场发射显示器的制备方法 | |
JP4930918B2 (ja) | ダイヤモンド製造方法 | |
JP4578694B2 (ja) | プラズマcvd装置およびプラズマcvd装置を用いたシリコン系膜の製造方法 | |
CN112695382A (zh) | 基于网格化结构电极提高金刚石异质外延形核均匀性的方法 | |
KR100629750B1 (ko) | 태양전지 dlc 반사 방지막의 제조방법 | |
US20190011770A1 (en) | Method of manufacturing nanowire grid polarizer |
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 |