CN108109931A - The caliper defects detection method of transparent film layer - Google Patents
The caliper defects detection method of transparent film layer Download PDFInfo
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- CN108109931A CN108109931A CN201711322252.6A CN201711322252A CN108109931A CN 108109931 A CN108109931 A CN 108109931A CN 201711322252 A CN201711322252 A CN 201711322252A CN 108109931 A CN108109931 A CN 108109931A
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- film layer
- transparent film
- region
- defects detection
- detection method
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- 230000007547 defect Effects 0.000 title claims abstract description 72
- 238000001514 detection method Methods 0.000 title claims abstract description 58
- 238000010894 electron beam technology Methods 0.000 claims abstract description 30
- 239000000758 substrate Substances 0.000 claims abstract description 19
- 239000000463 material Substances 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims abstract description 7
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 21
- 239000000377 silicon dioxide Substances 0.000 claims description 10
- 229910021419 crystalline silicon Inorganic materials 0.000 claims description 5
- 229910052710 silicon Inorganic materials 0.000 abstract description 13
- 239000010703 silicon Substances 0.000 abstract description 13
- 239000013078 crystal Substances 0.000 abstract description 9
- 230000009471 action Effects 0.000 abstract description 6
- 230000002776 aggregation Effects 0.000 abstract description 5
- 238000004220 aggregation Methods 0.000 abstract description 5
- 238000012545 processing Methods 0.000 abstract description 3
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 description 10
- 238000004519 manufacturing process Methods 0.000 description 6
- 239000000047 product Substances 0.000 description 6
- 230000003287 optical effect Effects 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- 239000004065 semiconductor Substances 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 210000004276 hyalin Anatomy 0.000 description 3
- 239000012528 membrane Substances 0.000 description 3
- 230000011664 signaling Effects 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000005611 electricity Effects 0.000 description 2
- 230000001788 irregular Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 206010021703 Indifference Diseases 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 150000001875 compounds Chemical class 0.000 description 1
- 230000002950 deficient Effects 0.000 description 1
- 238000013461 design Methods 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000003647 oxidation Effects 0.000 description 1
- 238000007254 oxidation reaction Methods 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 238000012797 qualification Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 238000009738 saturating Methods 0.000 description 1
- 229910052814 silicon oxide Inorganic materials 0.000 description 1
- 230000008719 thickening Effects 0.000 description 1
- 239000012780 transparent material Substances 0.000 description 1
- 238000009827 uniform distribution Methods 0.000 description 1
Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L22/00—Testing or measuring during manufacture or treatment; Reliability measurements, i.e. testing of parts without further processing to modify the parts as such; Structural arrangements therefor
- H01L22/10—Measuring as part of the manufacturing process
- H01L22/12—Measuring as part of the manufacturing process for structural parameters, e.g. thickness, line width, refractive index, temperature, warp, bond strength, defects, optical inspection, electrical measurement of structural dimensions, metallurgic measurement of diffusions
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- Engineering & Computer Science (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Microelectronics & Electronic Packaging (AREA)
- Power Engineering (AREA)
- Analysing Materials By The Use Of Radiation (AREA)
Abstract
The present invention provides a kind of caliper defects detection method of transparent film layer, and the caliper defects detection method of the transparent film layer includes:A region to be measured is provided, the region to be measured has transparent film layer;The region to be measured is irradiated by electron beam;The region to be measured is detected by electron beam defect detector.In the caliper defects detection method of transparent film layer provided by the invention, the transparent film layer in region to be measured is irradiated by electron beam, since material electronic action depth of the same race is identical, transparent film layer occur thickness it is thinning when, electronic action is on substrate crystal silicon, since the resistivity of transparent oxide film layer is less than substrate crystal silicon, oxide membranous layer aggregation electronics mostly with substrate silicon, it is that the oxide membranous layer more than electronics is thicker than dark region so as to detect bright region by electron beam defect detector, so as to effectively and accurately catch defect, the problem of finding in time in processing procedure, promote product yield.
Description
Technical field
The present invention relates to technical field of manufacturing semiconductors more particularly to a kind of caliper defects detection methods of transparent film layer.
Background technology
Since the complex process degree of semiconductor manufacturing constantly improves, in order to timely in actual production process
Pinpoint the problems and take appropriate measures, generally all can configure a certain number of defect detection equipments in manufacturing process.Defect
Detection device generally includes light microscope and electronic signal detection board, wherein, light microscope includes optics light field defect
Scanner and optics details in a play not acted out on stage, but told through dialogues Defect Scanning instrument, electronic signal detection board include scanning electron microscope and electron beam defects detection
Instrument.
At present, region to be measured that usually can be on wafer characterizes full wafer wafer using the thickness measure for sampling multiple points
Depth information;The thickness of transparent film layer can be obtained by sections observation cross section in development phase.The measurement of local thickness
See whether all cross section cannot all embody the thickness of product surface and the transparent film layer of various different pattern shapes comprehensively with section
Belong to normal range (NR).
At present the general defects detection in semiconductor fabrication process be can by optical light field in defect detection equipment and
Details in a play not acted out on stage, but told through dialogues principle is simultaneously compared according to optical signalling, so as to find out exception, then confirms defect situation.However for hyaline membrane
Layer, common optical signalling detection board cannot identify relatively thin transparent material, the thinning thickening almost indifference under optical signalling
It is different, the defects of None- identified goes out transparent film layer situation.
Therefore, it is those skilled in the art's skill urgently to be resolved hurrily how the caliper defects of transparent film layer to be detected
Art problem.
The content of the invention
It is an object of the invention to provide a kind of caliper defects detection method of transparent film layer, the thickness of transparent film layer is solved
Defects detection problem.
To solve the above-mentioned problems, the present invention provides a kind of caliper defects detection method of transparent film layer, the hyaline membrane
The caliper defects detection method of layer includes:
A region to be measured is provided, the region to be measured has transparent film layer;
The region to be measured is irradiated by electron beam;
The region to be measured is detected by electron beam defect detector.
Optionally, in the caliper defects detection method of the transparent film layer, when the transparent film layer hasMore than
Difference in height when, light and shade border region is observed by the electron beam defect detector.
Optionally, in the caliper defects detection method of the transparent film layer, along the line of demarcation of the light and shade border region
Another region to be measured is selected in direction, carries out the caliper defects detection of transparent film layer again.
Optionally, in the caliper defects detection method of the transparent film layer, the parameter of the electron beam includes:Voltage is
100V~800V, electric current are 10nA~50nA.
Optionally, in the caliper defects detection method of the transparent film layer, the quantity in the region to be measured be it is multiple, it is more
A region to be measured is uniformly distributed.
Optionally, in the caliper defects detection method of the transparent film layer, the thickness of the transparent film layer is more than or equal to
Optionally, in the caliper defects detection method of the transparent film layer, the material of the transparent film layer includes oxidation
Silicon.
Optionally, in the caliper defects detection method of the transparent film layer, the transparent film layer is located at crystalline silicon substrate
On.
Optionally, in the caliper defects detection method of the transparent film layer, further include:Recording detection data establishes number
According to storehouse.
Optionally, in the caliper defects detection method of the transparent film layer, the region to be measured include device area and/
Or inactive area.
In the caliper defects detection method of transparent film layer provided by the invention, the transparent of region to be measured is irradiated by electron beam
Film layer, since electronic action depth is identical, transparent film layer occur thickness it is thinning when, onto substrate crystal silicon, due to transparent oxygen
The resistivity of compound film layer be less than substrate crystal silicon, oxide membranous layer aggregation electronics mostly with substrate silicon, so as to pass through electricity
It is that the oxide membranous layer more than electronics is thicker than dark region that beamlet defect detector, which detects bright region, so as to effectively accurate
Ground catches defect, the problem of discovery in time in processing procedure, promotes product yield.
Description of the drawings
Fig. 1 is the flow chart of the caliper defects detection method of the transparent film layer of the embodiment of the present invention;
Fig. 2 is the diagrammatic cross-section of the transparent film layer of the embodiment of the present invention;
Fig. 3 is the caliper defects testing result schematic diagram of the transparent film layer of the embodiment of the present invention.
Specific embodiment
In order to enable objects, features and advantages of the present invention more obvious understandable, attached drawing is referred to.It should be clear that this explanation
Structure, ratio, size depicted in book institute accompanying drawings etc., only to coordinate the revealed content of specification, for being familiar with this
The personage of technology understands and reads, and is not limited to the enforceable qualifications of the present invention, therefore does not have technical essence meaning
Justice, the modification of any structure, the change of proportionate relationship or the adjustment of size are not influencing the effect of present invention can be generated and institute
Under the purpose that can reach, should all still it fall in the range of disclosed technology contents are obtained and can covered.
As depicted in figs. 1 and 2, the caliper defects detection method of a kind of transparent film layer provided by the invention, the hyaline membrane
The caliper defects detection method of layer includes:
Step S10, a region to be measured is provided, the region to be measured has transparent film layer;
Step S20, the region to be measured is irradiated by electron beam;
Step S30, the region to be measured is detected by electron beam defect detector.
Each step in the caliper defects detection method for introducing transparent film layer in greater detail below.
First, a region to be measured is provided by step S10, such as three chips that can be used at least wafer are examined
It surveys, the present embodiment relates generally to semiconductor fabrication, what region to be measured can be formed positioned at crystal column surface and other needs
The region of certain area, it is ensured that at least there are three same areas with comparing, and may serve to be detected, described to be measured
Region has transparent film layer, and the depth information of transparent film layer generally can not be detected preferably by optical defect detection device.
In order to preferably embody testing result, the quantity in the region to be measured is multiple, and multiple regions to be measured are uniform
Distribution, wherein the same area for being uniformly distributed the different chips for being included in wafer realizes uniform design, the face of measured device
It is long-pending larger or irregular etc., the surface area for needing to detect can be divided into multiple parts continuously or discontinuously, pass through inspection
Selected region to be measured is surveyed so as to can determine testing result, the time can be saved for the product of large area, and passes through opposite mark
The setting of standardization is so as to unified testing result, for irregular product area, by equally distributed selected available more accurate
True testing result, be uniformly distributed the various ways such as selection to be realized by product type by symmetric mode or in proportion
Point.
In the present embodiment, the thickness of the transparent film layer is more than or equal toThe thickness of transparent film layer refers to positive reason
Under condition or the index of standard parameter, when the thickness of transparent film layer is smaller, electron beam acts on region to be measured, electronics aggregate amount
Difference is not enough to embody preferably detect the exception of transparent film layer by gray difference.
Optionally, the material of the transparent film layer includes silica, when electron irradiation is on silicon oxide layer, utilizes electron beam
The resistivity of the base material of signal source, silica and silica is different, and silica is thinning direct even without electrons afterwards
Act in base material, the resistance of generation can be much larger than silica, therefore can detect silica or silica it is thick some
Region part can be brighter, and silica it is thinning or without region part can be dark, the thickness so as to distinguish silica is
It is no the exception such as thinning occur, it is adaptable to the detection of other transparent film layers.
Optionally, the transparent film layer is located in crystalline silicon substrate, the bottom material using crystalline silicon substrate as transparent film layer
Material, transparent film layer is can be formed directly in crystalline silicon substrate, then carries out subsequent technique again.
Then, the region to be measured is irradiated by electron beam by step S20, beam signal acts on region table to be measured
Face, electronic action depth is identical, transparent film layer occur thickness it is thinning when, electron beam is applied on substrate crystal silicon, due to saturating
The resistivity of bright oxide membranous layer is less than substrate crystal silicon, oxide membranous layer aggregation electronics mostly with substrate silicon, so as to logical
It is that the oxide membranous layer more than electronics is thicker than dark region to cross electron beam defect detector and detect bright region.
Optionally, the parameter of the electron beam includes:Voltage is 100V~800V, and electric current is 10nA~50nA, by right
The requirement of different-thickness and material etc. can be corresponded to by generating the parameter setting of electron beam, for example, the setting of voltage include 100V,
200V, 300V, 400V, 500V, 600V, 700V or 800V, the setting of electric current include 10nA, 20nA, 30nA, 40nA or 50nA.
Then, according to step S30, the region to be measured is detected by electron beam defect detector, obtains region to be measured
Surface so as to observe whether transparent film layer abnormal conditions occurs, effectively accurately determines defect.
With continued reference to shown in Fig. 2, when the transparent film layer hasDuring above difference in height, i.e. the thickness of transparent film layer
Situations such as uneven, occursAbove difference in height, the thickness such as B1 areas transparents film layer in figure is thicker than B2 region,
Light and shade border region is observed by the electron beam defect detector, when electron beam irradiates, electronic action depth is identical, when
When going out rugged difference in height, electron beam penetrates transparent film layer and reaches substrate, and it is uneven to show the resistance in region to be measured, figure
Correspondence shown in 2 can be as shown in part B in Fig. 3, and B2 areas transparent thicknesses of layers R2 is less than B1 areas transparent thicknesses of layers R1, simultaneously
The resistivity of transparent film layer is less than resistance substrate rate so that is less than B1 regions in the electronics of B2 zone focusings, therefore shows electricity
It is dark or black that son, which assembles few B2 regions, and the B1 regions more than electronics aggregation are shown as bright, can be showed with this
In the abnormal conditions of bright film layer, wherein Fig. 3 part A show transparent film layer thickness it is normal when observable obtain.
In order to further detect, another region to be measured is selected along the line of demarcation direction of the light and shade border region, again into
The caliper defects detection of row transparent film layer when light and shade border region occurs in region to be measured, is selected another again in line of demarcation direction
One region to be measured, that is, in order to expand detection range, better region is detected by the movement along bright-dark cut whether
Also caliper defects are had, since light and shade boundary is by being linear, the bright-dark cut direction direction that i.e. its edge is stretched, so as to
It further determines that scope of the caliper defects of transparent film layer etc., three chips can at least be selected to pass through in a particular embodiment
Scanning comparison carries out the caliper defects detection of transparent film layer, i.e., can also be between different chips along bright-dark cut direction
Come carry out.Light and shade boundary can be presented in the entire selected areas end of scan, can be by the comparison of at least three same areas come body
The position of existing thickness abnormity.
For the ease of analysis, the caliper defects detection method of the transparent film layer further includes:Recording detection data establishes number
According to storehouse, detection data can include product information, defective locations/size, quantity etc., can directly embody detection in the database
As a result.
Optionally, the region to be measured includes device area and/or inactive area, and device area can form various devices
The resulting structures such as structure, inactive area is the indirect region worked or white space etc., due to the transparent film layer of formation
It usually can all include device area and inactive area, the thickness of transparent film layer can be embodied from different aspect in different regions
Degree situation.
In the caliper defects detection method of transparent film layer provided by the invention, the transparent of region to be measured is irradiated by electron beam
Film layer, electronic action depth is identical, transparent film layer occur thickness it is thinning when, electron beam is applied on substrate crystal silicon, due to
The resistivity of transparent oxide film layer be less than substrate crystal silicon, oxide membranous layer aggregation electronics mostly with substrate silicon, so as to
It is that the oxide membranous layer more than electronics is thicker than dark region to detect bright region by electron beam defect detector, so as to have
Effect catches defect exactly, the problem of discovery in time in processing procedure, promotes product yield.
Foregoing description is only the description to present pre-ferred embodiments, not to any restriction of the scope of the invention, this hair
Any change, the modification that the those of ordinary skill in bright field does according to the disclosure above content, belong to the protection of claims
Scope.
Claims (10)
- A kind of 1. caliper defects detection method of transparent film layer, which is characterized in that the caliper defects detection side of the transparent film layer Method includes:A region to be measured is provided, the region to be measured has transparent film layer;The region to be measured is irradiated by electron beam;The region to be measured is detected by electron beam defect detector.
- 2. the caliper defects detection method of transparent film layer as described in claim 1, which is characterized in that when the transparent film layer has HaveDuring above difference in height, light and shade border region is observed by the electron beam defect detector.
- 3. the caliper defects detection method of transparent film layer as claimed in claim 2, which is characterized in that along the light and shade watershed area Another region to be measured is selected in the line of demarcation direction in domain, carries out the caliper defects detection of transparent film layer again.
- 4. the caliper defects detection method of transparent film layer as described in claim 1, which is characterized in that the parameter of the electron beam Including:Voltage is 100V~800V, and electric current is 10nA~50nA.
- 5. the caliper defects detection method of transparent film layer as described in claim 1, which is characterized in that the number in the region to be measured It measures to be multiple, multiple regions to be measured are uniformly distributed.
- 6. the caliper defects detection method of transparent film layer as described in claim 1, which is characterized in that the thickness of the transparent film layer Degree is more than or equal to
- 7. the caliper defects detection method of transparent film layer as described in claim 1, which is characterized in that the material of the transparent film layer Material includes silica.
- 8. the caliper defects detection method of transparent film layer as described in claim 1, which is characterized in that the transparent film layer is located at In crystalline silicon substrate.
- 9. the caliper defects detection method of transparent film layer as claimed in any of claims 1 to 8 in one of claims, which is characterized in that institute The caliper defects detection method for stating transparent film layer further includes:Recording detection data establishes database.
- 10. the caliper defects detection method of transparent film layer as claimed in any of claims 1 to 8 in one of claims, which is characterized in that institute Stating region to be measured includes device area and/or inactive area.
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5811803A (en) * | 1996-08-23 | 1998-09-22 | Kabushiki Kaisha Toshiba | Electron microscope |
JP2006352170A (en) * | 2006-09-25 | 2006-12-28 | Hitachi Ltd | Inspection method for wafer |
US20110284063A1 (en) * | 2010-05-24 | 2011-11-24 | Miao Yu | High efficiency dye-sensitized solar cell with layered structures |
CN102487026A (en) * | 2010-12-02 | 2012-06-06 | 中芯国际集成电路制造(北京)有限公司 | Method for detecting defect of through holes |
-
2017
- 2017-12-12 CN CN201711322252.6A patent/CN108109931B/en active Active
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5811803A (en) * | 1996-08-23 | 1998-09-22 | Kabushiki Kaisha Toshiba | Electron microscope |
JP2006352170A (en) * | 2006-09-25 | 2006-12-28 | Hitachi Ltd | Inspection method for wafer |
US20110284063A1 (en) * | 2010-05-24 | 2011-11-24 | Miao Yu | High efficiency dye-sensitized solar cell with layered structures |
CN102487026A (en) * | 2010-12-02 | 2012-06-06 | 中芯国际集成电路制造(北京)有限公司 | Method for detecting defect of through holes |
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Address after: 430205 No.18, Gaoxin 4th Road, Donghu Development Zone, Wuhan City, Hubei Province Patentee after: Wuhan Xinxin Integrated Circuit Co.,Ltd. Country or region after: China Address before: 430205 No.18, Gaoxin 4th Road, Donghu Development Zone, Wuhan City, Hubei Province Patentee before: Wuhan Xinxin Semiconductor Manufacturing Co.,Ltd. Country or region before: China |