CN218747087U - Chemical mechanical polishing trimmer - Google Patents
Chemical mechanical polishing trimmer Download PDFInfo
- Publication number
- CN218747087U CN218747087U CN202223305511.3U CN202223305511U CN218747087U CN 218747087 U CN218747087 U CN 218747087U CN 202223305511 U CN202223305511 U CN 202223305511U CN 218747087 U CN218747087 U CN 218747087U
- Authority
- CN
- China
- Prior art keywords
- chemical mechanical
- mechanical polishing
- abrasive particles
- area
- groove
- 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.)
- Active
Links
Images
Landscapes
- Grinding-Machine Dressing And Accessory Apparatuses (AREA)
Abstract
The utility model relates to a chemical mechanical polishing trimmer, chemical mechanical polishing trimmer includes: the abrasive disc comprises a disc base body, grooves and abrasive particles fixed on the disc base body, wherein the grooves are distributed on the surface of the disc base body, and the abrasive particles are distributed outside the groove area; the utility model relates to a chemical mechanical polishing trimmer is through at the surface design slot, is favorable to the discharge of piece and grinding accessory substance, reduces the risk of wafer fish tail, avoids piece adhesion between abrasive particles simultaneously, prolongs the working life of trimmer, in addition, because trimmer design of surface has the slot, can also promote the more even distribution of polishing solution, improves grinding efficiency, and this chemical mechanical polishing trimmer simple structure, the processing and production of being convenient for.
Description
Technical Field
The utility model belongs to the technical field of semiconductor integrated circuit makes, in particular to be used for chip chemical mechanical polishing trimmer.
Background
In a semiconductor process flow, chemical Mechanical Polishing (Chemical Mechanical Polishing) is a very important process. During chemical mechanical polishing, a wafer is contacted with a polishing pad under a certain pressure, the surface of the wafer and polishing liquid are subjected to chemical reaction, a formed chemical reactant is removed under the mechanical action, the polishing pad is a polyurethane material with micropores, and in the chemical mechanical polishing process, fragments generated by grinding can block the micropores of the polishing pad, so that the roughness of the surface of the polishing pad is reduced, glazing is easy to occur, so that the polishing performance is reduced, and therefore, the dresser is required to timely dress the surface of the polishing pad, keep the surface of the polishing pad rough, and timely remove the grinding fragments.
The traditional chemical mechanical polishing dresser usually uses a complete disc matrix, abrasive particles are arranged on the whole matrix of the dresser through brazing and sintering processes, a chip removal channel is not designed, a shallow groove with the height smaller than 100 mu m can be obtained by controlling a drill distribution area through an electroplating process, the chip removal space is limited, and in the working process of the dresser, scraps and byproducts on a polishing pad are not easy to discharge and remain in gaps among the abrasive particles, so that micropores on the surface of the polishing pad are easy to block, and the polishing performance is reduced; on the other hand, if the grinding debris is not cleaned in time, the wafer can be scratched, the wafer yield is reduced, and the production cost is increased.
Therefore, there is a need for a new dresser for chemical mechanical polishing, which can effectively remove the polishing debris while dressing the surface of the polishing pad during the chemical mechanical polishing process.
SUMMERY OF THE UTILITY MODEL
In view of the problem that exists among the prior art, the utility model aims to provide a chemical mechanical polishing trimmer with slot type chip groove to solve among the prior art on the polishing pad grind piece discharge efficiency low, the polishing solution distributes inhomogeneous and the higher problem of wafer fish tail risk.
The utility model provides a chemical mechanical polishing trimmer, including the disc base member, wherein disc base member upper surface contains the inside and leaves white the region, the slot region, and the region of keeping white is maintained to the trimming region and outside, inside leaves white region, outside and leaves white the region, the disc base member and is distributed for concentric circles, and the outside diameter that the outside left white the region equals with the diameter of disc base member, the slot region is located between the outside leaves white the region and the inside with the trimming region, include one or more slots in the slot region, it contains abrasive particles to maintain the regional interior, inside leaves white the region, outside leaves white the region and the slot region does not contain abrasive particles;
further, the groove shape comprises one or more combination of straight line radiation type, arc line radiation type, spiral type and concentric circle type;
further, the depth of the groove is between 0.1 and 10mm, and the width of the groove is between 1 and 10 mm;
further, the cross-sectional shape of the groove comprises one of square, arc, U and V;
furthermore, the groove is obtained by machining or laser cutting the disc substrate;
further, the abrasive particles comprise one of diamond, cubic boron nitride, fused alumina, ceramic alumina, heat treated alumina, silicon carbide, boron carbide, alumina zirconia, iron oxide, ceria, garnet;
further, the particle size range of the abrasive particles is between 100 and 300 microns, and the spacing between the abrasive particles is between 100 and 1000 microns;
further, the abrasive particles are fixed on the disc base body through one of a brazing process, a sintering process and an electroplating process;
further, the disc base material is one of stainless steel and polycarbonate plastic;
further, the diameter of the disc base body is 108mm.
The utility model has the advantages that: the chemical mechanical polishing dresser with the groove-type chip groove provided by the utility model is beneficial to discharging scraps and grinding byproducts through the groove design, reduces the risk of scratching the wafer, can also effectively reduce the loss of abrasive particles on the surface of the dresser substrate, and prolongs the service life of the dresser; meanwhile, the polishing solution can be more uniformly distributed, and the grinding efficiency is improved.
Drawings
Fig. 1 is a schematic structural view of a cmp conditioner according to embodiment 1 of the present invention;
fig. 2 is a schematic structural view of a cmp conditioner according to embodiment 2 of the present invention;
fig. 3 is a schematic structural view of a cmp conditioner according to embodiment 3 of the present invention;
fig. 4 is a schematic structural view of a cmp conditioner according to embodiment 4 of the present invention;
fig. 5 is a schematic structural view of a cmp conditioner according to embodiment 5 of the present invention;
FIG. 6 is a cross-sectional view of a conditioner of the present invention with a small amount of abrasive debris remaining between the grooves and abrasive particles during polishing;
FIG. 7 is a cross-sectional view of a dresser resulting from a prior art brazing and sintering process during polishing with abrasive debris remaining between the abrasive particles;
FIG. 8 is a cross-sectional view of a prior art dresser using an electroplating process having grinding debris remaining between abrasive grains during polishing;
reference numerals
11-disc matrix, 12-grooves, 13-abrasive particles, 14-grinding chips.
Detailed Description
As before, the utility model provides a chemical mechanical polishing trimmer with slot chip groove, including the disc base member, the utility model provides a disc base member selects to use the size that this area is commonly used, and the diameter is 108mm, wherein disc base member upper surface contains inside blank area to and outside blank area, and inside blank area, outside blank area, be the concentric circles with the disc base member and distribute, and wherein the regional diameter of inside blank area is between 14 ~ 18mm, and is preferred, and the regional diameter of inside blank area is 16mm, and outside blank area is the annular design, and outside blank area's external diameter equals with the external diameter of disc base member, and annular width is 3 ~ 5mm, and preferred annular width is 4mm, and processing is convenient for, and outside blank area is provided with the chamfer with the junction around the disc base member.
The utility model discloses the regional surface of the inside area of remaining white that relates to in and outside area of remaining white all not inlayed and have the abrasive grain.
The utility model discloses in, include slot region and finishing region between inside blank leaving region and the outside blank leaving region, the slot shape includes one or more combinations in sharp radial, pitch arc radial, screw-tupe, the concentric circles, and is preferred, and the slot shape is one in sharp radial, pitch arc radial, the screw-tupe, and is particularly preferred, and the slot shape is one in sharp radial or the pitch arc radial.
The utility model discloses an in the embodiment, straight line radial line slot or pitch arc radial line slot extend to outside from inside blank area and leave white regional, and every slot distributes in disc base member surface with fixed central angle, and wherein the quantity of straight line radial line slot and pitch arc radial line slot is between 2 ~ 32, and is preferred, and the quantity of straight line radial line slot and pitch arc radial line slot is between 6 ~ 16, and is particularly preferred, and the quantity of straight line radial line slot and pitch arc radial line slot is between 8 ~ 12.
In another embodiment of the present invention, the concentric circular grooves are distributed concentrically with the inner blank area and the outer blank area, wherein the distance between different concentric circular grooves is equal along the diameter direction, wherein the number of concentric circular grooves is between 3 and 8, preferably, the number of concentric circular grooves is between 3 and 5.
In another embodiment of the present invention, the radiation-emitting device comprises a concentric circular and linear radiation-type combined slot, wherein the linear radiation-type slot extends from the inner blank-keeping area to the outer blank-keeping area, wherein the number of the linear radiation-type slots is between 6 and 12, preferably, the number of the linear radiation-type slots is between 6 and 8; the concentric circular grooves are distributed in concentric circles with the inner blank area and the outer blank area, wherein the distance between different concentric circular grooves is equal along the diameter direction, the number of the concentric circular grooves is 3-8, and preferably, the number of the concentric circular grooves is 3-5.
The utility model discloses well slot optional use machining or laser cutting's mode obtains, preferred, the utility model provides a slot uses machining's mode to obtain, the utility model provides a well slot leaves white region and inside to leave white regional junction and be provided with the chamfer with the outside.
In the utility model, the depth of the groove is between 0.1 mm and 5mm, preferably, the depth of the groove is between 0.1 mm and 3mm, particularly preferably, the depth of the groove is between 0.1 mm and 1mm, in consideration of smooth discharge of the scraps and more uniform distribution of the polishing solution; the groove width is between 0.1 and 10mm, preferably between 0.1 and 5mm, particularly preferably between 0.1 and 1 mm.
The utility model discloses in arbitrary one in the optional square of slot cross sectional shape, circular arc type, U type, the V type, consider the volume size problem of slot to and the degree of difficulty of processing, this novel preferred slot cross sectional shape of use is the square.
The utility model discloses well finishing region distributes on the disc base member, and include a plurality of finishing regions on the disc base member, every finishing region is left white regional by inside, the outside is left white regional and slot partition and is formed, wherein it has abrasive particles to keep white regional distribution, abrasive particles includes diamond, cubic boron nitride, fused alumina, ceramic alumina, heat treatment's alumina, carborundum, boron carbide, alumina-zirconia, ferric oxide, ceric oxide, among the garnet one, preferably, abrasive particles contains diamond or one among the cubic boron nitride.
In the utility model, the grain size range of the abrasive particles is between 100 and 300 μm, preferably between 150 and 250 μm, because of the high suitability of the abrasive particles on the surface of the dresser for edging and the balance of the cutting and removing capability; the spacing between adjacent abrasive particles is between 100 and 1000 μm, preferably between 400 and 800 μm.
The utility model discloses well abrasive particles fixes on the disc base member through common technology among the prior art, and is selectable, including one of brazing process, sintering process or electroplating process, preferred, the utility model provides a abrasive particles fixes on the disc base member through electroplating process.
The utility model discloses well disc matrix material is one of stainless steel, polycarbonate plastics, and is preferred, and disc matrix material is the stainless steel.
Example 1
In the embodiment, a stainless steel material is selected as a disc base material of the chemical mechanical polishing dresser, the diameter of the disc base material is 108mm, the diameter of an inner blank area is 16mm, the width of an outer blank area along the diameter direction is 4mm, and a chamfer is arranged at the edge of the outer blank area; the groove area uses arc radial type grooves, the number of the grooves is 12, the width of the groove is 1mm, the depth of the groove is 1mm, and the section is square; the trimming area is provided with diamond abrasive particles, the diamond abrasive particles are 150-250 microns diamond particles, the particle spacing between the diamond particles is 600 microns, in the embodiment, the grooves are obtained through a machining process, and the abrasive particles are fixed on the disc base body in an electroplating mode.
Example 2
The dimensions of the disc base material and the blank area of the chemical mechanical polishing dresser in the embodiment are the same as those of the embodiment 1, and the difference is that the shape and the dimension of the groove area are different; wherein the groove area uses linear radial grooves, the number of the grooves is 8, the width of the groove is 1mm, the depth of the groove is 1.5mm, and the section is square; the trimming area is provided with diamond abrasive grains, the diamond abrasive grains are 150-250 micrometers, the grain spacing between the diamond grains is 500 micrometers, in the embodiment, the grooves are obtained through a machining process, and the abrasive grains are fixed on the disc base body in an electroplating mode.
Example 3
The dimensions of the disc base material and the blank area of the chemical mechanical polishing dresser in the embodiment are the same as those of the embodiment 1, and the difference is that the shape and the dimension of the groove area are different; the groove area uses concentric circular grooves, the number of the grooves is 3 concentric circles, the width of the grooves is 3mm, the depth of the grooves is 2mm, and the section of the grooves is square; the trimming area is provided with diamond abrasive particles, the diamond abrasive particles are 150-250 microns diamond particles, the spacing between the diamond particles is 400 microns, in the embodiment, the grooves are obtained through a machining process, and the abrasive particles are fixed on the disc base body in an electroplating mode.
Example 4
The dimensions of the disc base material and the blank area of the chemical mechanical polishing dresser in the embodiment are the same as those of the embodiment 1, and the difference is that the shape and the dimension of the groove area are different; the groove area uses a concentric circular groove and a linear radial line type groove to combine grooves, the number of the grooves is the combination of 3 concentric circles and eight linear radial line grooves, the width of the concentric circle groove is 3mm, the depth of the groove is 2mm, the width of the linear radial line groove is 1mm, the depth of the groove is 2mm, and the section is square; the trimming area is provided with diamond abrasive particles, the diamond abrasive particles are 150-250 microns diamond particles, the spacing between the diamond particles is 400 microns, in the embodiment, the grooves are obtained through a machining process, and the abrasive particles are fixed on the disc base body in an electroplating mode.
Example 5
The dimensions of the disc base material and the blank area of the chemical mechanical polishing dresser in the embodiment are the same as those of the embodiment 1, and the difference is that the shape and the dimension of the groove area are different; the groove area uses arc radial type grooves, the number of the grooves is 8, the width of the groove is 5mm, the depth of the groove is 2mm, and the section is square; the trimming area is provided with diamond abrasive particles, the diamond abrasive particles are 150-250 microns diamond particles, the spacing between the diamond particles is 200 microns, in the embodiment, the grooves are obtained through a machining process, and the abrasive particles are fixed on the disc base body in an electroplating mode.
Comparative example 1
The dimensions of the disc matrix material and the blank area of the chemical mechanical polishing dresser in the embodiment are the same as those of the embodiment 1, the disc matrix material and the blank area do not contain a groove area, diamond particles with the particle size of 150-250 mu m are selected as the diamond abrasive particles, the distance between the diamond particles is 600 mu m, and the abrasive particles are fixed on the disc matrix in a brazing mode.
Comparative example 2
The dimensions of the disc base material and the blank region of the cmp conditioner in this example were the same as those in example 1, except that the depth of the groove region was 0mm, that is, the original groove in this comparative example was a blank region communicating with the inner blank region and the outer blank region; wherein the trimming area is provided with diamond abrasive particles, the diamond abrasive particles are 150-250 μm diamond particles, the inter-particle distance between the diamond particles is 600 μm, and the abrasive particles are fixed on the disc substrate in an electroplating mode.
Evaluation of CMP conditioner:
the CMP pad dressers of the prepared examples and comparative examples were subjected to the on-machine test under the following conditions:
the testing machine is AMAT Refelxion (Modify 5 Zone);
the polishing pad is a DH3000 series polishing pad controlled by Dinglong;
the polishing solution is ANJI U3061A (slurry (g): DIW (g): 30% H 2 O 2 (g) =1, 10), flow rate 300mL/min;
the chemical mechanical polishing dresser was the chemical mechanical polishing dresser prepared in examples 1 to 5 and comparative examples 1 and 2;
Zone Pressure：RR/Z1/Z2/Z3/Z4/Z5:5.90/5.10/2.40/2.15/2.10/2.20；
the wafers (wafers) used were Pattern wafers Semitech 754, cu Blanket wafer Pre Thickness 10-12 KA.
Evaluating the quantity of defects generated on the wafer surface of different CMP conditioners under the same condition so as to determine the performance of the CMP conditioners, wherein the Defect evaluation method comprises the following steps: available from Cotex corporation (KLA-Tencor)
The SP2 defect inspection system performs inspection and detects the size of the defect: 0.16 μm.
Evaluation results were as follows: the cmp conditioner with grooves according to examples 1 to 5 had very few wafer surface defects and good performance after evaluation for 20 hours, and the abrasive debris was present in large amounts in the grooves, facilitating the discharge of the abrasive debris, as shown in fig. 6; after 20 hours evaluation of the cmp conditioner without grooves prepared by the brazing process in comparative example 1, the wafer surface had more defects, the surface had no grooves for chip removal, and grinding debris existed between diamond particles, as shown in fig. 7, causing scratching of the wafer; the cmp conditioner of comparative example 2, which was evaluated for 20 hours, had a small amount of defect on the wafer surface and also had no grooves for chip removal even though a blank region communicating the central blank region and the outer blank region was present on the wafer surface, as shown in fig. 8, and had a limited ability to store and discharge abrasive debris, and thus had no good performance.
The chemical mechanical polishing dressing disk and the preparation method thereof provided by the utility model are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are presented only to assist in understanding the method and its core concepts. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (10)
1. A chemical mechanical polishing dresser is characterized by comprising a disk substrate, wherein the upper surface of the disk substrate comprises an inner blank area, a groove area, a dressing area and an outer blank area, the inner blank area, the outer blank area and the disk substrate are distributed in a concentric circle mode, the outer diameter of the outer blank area is equal to the diameter of the disk substrate, the groove area and the dressing area are located between the outer blank area and the inner blank area, one or more grooves are contained in the groove area, abrasive particles are contained in the dressing area, and the inner blank area, the outer blank area and the groove area do not contain the abrasive particles.
2. The chemical mechanical polishing conditioner of claim 1 wherein the groove shape comprises one or more combinations of straight radial lines, curved radial lines, spirals, concentric circles.
3. The chemical mechanical polishing conditioner of claim 1 wherein said grooves have a depth of between 0.1 and 10mm and a width of between 1 and 10 mm.
4. The chemical mechanical polishing conditioner of claim 1 wherein said groove cross-sectional shape comprises one of square, circular, U-shaped, V-shaped.
5. The chemical mechanical polishing conditioner of claim 1 wherein said grooves are machined or laser cut into the disk substrate.
6. The cmp conditioner of claim 1, wherein the abrasive particles comprise one of diamond, cubic boron nitride, fused alumina, ceramic alumina, heat treated alumina, silicon carbide, boron carbide, alumina zirconia, iron oxide, ceria, and garnet.
7. The chemical mechanical polishing conditioner of claim 1 wherein said abrasive particles have a size ranging from 100 to 300 μm and a spacing between abrasive particles ranging from 100 to 1000 μm.
8. The chemical mechanical polishing conditioner of claim 1 wherein said abrasive particles are affixed to said disk substrate by one of a brazing process, a sintering process, and an electroplating process.
9. The chemical mechanical polishing conditioner of claim 1 wherein said disc substrate material is one of stainless steel, polycarbonate plastic.
10. The chemical mechanical polishing conditioner of claim 1 wherein said disk substrate has a diameter of 108mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223305511.3U CN218747087U (en) | 2022-12-08 | 2022-12-08 | Chemical mechanical polishing trimmer |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202223305511.3U CN218747087U (en) | 2022-12-08 | 2022-12-08 | Chemical mechanical polishing trimmer |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN218747087U true CN218747087U (en) | 2023-03-28 |
Family
ID=85682817
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202223305511.3U Active CN218747087U (en) | 2022-12-08 | 2022-12-08 | Chemical mechanical polishing trimmer |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN218747087U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117798814A (en) * | 2024-03-01 | 2024-04-02 | 浙江大学杭州国际科创中心 | Polishing pad, preparation method of polishing pad and polishing method |
-
2022
- 2022-12-08 CN CN202223305511.3U patent/CN218747087U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117798814A (en) * | 2024-03-01 | 2024-04-02 | 浙江大学杭州国际科创中心 | Polishing pad, preparation method of polishing pad and polishing method |
| CN117798814B (en) * | 2024-03-01 | 2024-05-28 | 浙江大学杭州国际科创中心 | Polishing pad, preparation method of polishing pad and polishing method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100609361B1 (en) | Super Grooved Chips and Super Grooved Tools | |
| EP1319470B1 (en) | Ultra abrasive grain wheel for mirror finish | |
| KR101339722B1 (en) | CMP Pad conditioner | |
| JP2004098214A (en) | Dresser for polishing cloth and dressing method for polishing cloth using the same | |
| KR20000024453A (en) | Conditioner for polishing pad and method of manufacturing the same | |
| US10414020B2 (en) | Grindstone and grinding/polishing device using same | |
| JPH1071549A (en) | Chamfering device and chamfering method of wafer by using free abrasive grain | |
| CN218747087U (en) | Chemical mechanical polishing trimmer | |
| EP0092818B1 (en) | Method for grinding the surface of a semiconductor wafer | |
| CN102049737B (en) | Polishing pad conditioner | |
| CN1666844A (en) | Dresser for polishing cloth and method for producing the same | |
| EP3530409A1 (en) | Grindstone | |
| KR20090013366A (en) | Conditioning Discs for Polishing Pads | |
| CN113211334A (en) | Self-sharpening resin binder diamond grinding wheel and preparation method thereof | |
| JP2006055944A (en) | Cmp pad conditioner | |
| KR200175263Y1 (en) | The structure of the conditioner for CMP(Chemical Mechanical Polishing) Pad in CMP process | |
| JP4746788B2 (en) | Super-abrasive wheel for surface honing, dressing method thereof, and grinding apparatus using the wheel | |
| CN113199400A (en) | Chemical mechanical grinding polishing pad dressing device and preparation method thereof | |
| JP2011020182A (en) | Polishing tool suitable for pad conditioning, and polishing method using the same | |
| CN110871407A (en) | Pad conditioner and method for chemical mechanical planarization | |
| JP2003170356A (en) | Diamond coating cutting tool | |
| JPH1058331A (en) | Super abrasive grain wheel for lapping | |
| TWI735795B (en) | Polishing pad dresser and chemical mechanical planarization method | |
| JP2006218577A (en) | Dresser for polishing cloth | |
| JP2004243465A (en) | Diamond lapping surface plate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20231113 Address after: 430058 Wuhan Economic and Technological Development Zone Export Processing Zone 25MC Block Diamond Tool Export Processing Production Base Project Phase I A6 Factory Building in Wuhan, Hubei Province Patentee after: Wuhan Dinglong Huida Material Technology Co.,Ltd. Address before: 430057 Room 411, No.1 dongjinghe Road, Wuhan Economic and Technological Development Zone, Hubei Province Patentee before: HUBEI DINGHUI MICROELECTRONICS MATERIALS Co.,Ltd. Patentee before: Wuhan Dinglong Huida Material Technology Co.,Ltd. Patentee before: HUBEI DINGLONG Co.,Ltd. |
|
| CP03 | Change of name, title or address | ||
| CP03 | Change of name, title or address |
Address after: 430058 Wuhan Economic and Technological Development Zone Export Processing Zone 25MC Block Diamond Tool Export Processing Production Base Project Phase I A6 Factory Building in Wuhan, Hubei Province Patentee after: Wuhan Huida Material Technology Co.,Ltd. Country or region after: China Address before: 430058 Wuhan Economic and Technological Development Zone Export Processing Zone 25MC Block Diamond Tool Export Processing Production Base Project Phase I A6 Factory Building in Wuhan, Hubei Province Patentee before: Wuhan Dinglong Huida Material Technology Co.,Ltd. Country or region before: China |