Classifications

• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/708—Construction of apparatus, e.g. environment aspects, hygiene aspects or materials
  • G03F7/70991—Connection with other apparatus, e.g. multiple exposure stations, particular arrangement of exposure apparatus and pre-exposure and/or post-exposure apparatus; Shared apparatus, e.g. having shared radiation source, shared mask or workpiece stage, shared base-plate; Utilities, e.g. cable, pipe or wireless arrangements for data, power, fluids or vacuum
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/0002—Lithographic processes using patterning methods other than those involving the exposure to radiation, e.g. by stamping
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
  • G03F7/70491—Information management, e.g. software; Active and passive control, e.g. details of controlling exposure processes or exposure tool monitoring processes
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
  • G03F7/70491—Information management, e.g. software; Active and passive control, e.g. details of controlling exposure processes or exposure tool monitoring processes
  • G03F7/70525—Controlling normal operating mode, e.g. matching different apparatus, remote control or prediction of failure
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
  • G03F7/70491—Information management, e.g. software; Active and passive control, e.g. details of controlling exposure processes or exposure tool monitoring processes
  • G03F7/70533—Controlling abnormal operating mode, e.g. taking account of waiting time, decision to rework or rework flow
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
  • G03F7/70605—Workpiece metrology
  • G03F7/70616—Monitoring the printed patterns
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
  • G03F7/70605—Workpiece metrology
  • G03F7/70616—Monitoring the printed patterns
  • G03F7/70625—Dimensions, e.g. line width, critical dimension [CD], profile, sidewall angle or edge roughness
• • G—PHYSICS
  • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
  • G03F—PHOTOMECHANICAL PRODUCTION OF TEXTURED OR PATTERNED SURFACES, e.g. FOR PRINTING, FOR PROCESSING OF SEMICONDUCTOR DEVICES; MATERIALS THEREFOR; ORIGINALS THEREFOR; APPARATUS SPECIALLY ADAPTED THEREFOR
  • G03F7/00—Photomechanical, e.g. photolithographic, production of textured or patterned surfaces, e.g. printing surfaces; Materials therefor, e.g. comprising photoresists; Apparatus specially adapted therefor
  • G03F7/70—Microphotolithographic exposure; Apparatus therefor
  • G03F7/70483—Information management; Active and passive control; Testing; Wafer monitoring, e.g. pattern monitoring
  • G03F7/70605—Workpiece metrology
  • G03F7/70616—Monitoring the printed patterns
  • G03F7/70633—Overlay, i.e. relative alignment between patterns printed by separate exposures in different layers, or in the same layer in multiple exposures or stitching
• • H—ELECTRICITY
  • H10—SEMICONDUCTOR DEVICES; ELECTRIC SOLID-STATE DEVICES NOT OTHERWISE PROVIDED FOR
  • H10P—GENERIC PROCESSES OR APPARATUS FOR THE MANUFACTURE OR TREATMENT OF DEVICES COVERED BY CLASS H10
  • H10P76/00—Manufacture or treatment of masks on semiconductor bodies, e.g. by lithography or photolithography
  • H10P76/20—Manufacture or treatment of masks on semiconductor bodies, e.g. by lithography or photolithography of masks comprising organic materials
  • H10P76/204—Manufacture or treatment of masks on semiconductor bodies, e.g. by lithography or photolithography of masks comprising organic materials of organic photoresist masks
  • H10P76/2041—Photolithographic processes

Definitions

• the present invention relates to the field of metrology, and more particularly, to optimized lithography systems.
• Lithography system have to handle continuously growing complexity, smaller printing nodes and increases in metrology input, within shrinking printing time requirements.
• One aspect of the present invention provides a lithography system comprising: a printing tool with an integrated metrology tool, and a standalone metrology tool connected to the printing tool and configured to perform metrology measurements on wafers produced by the printing tool, wherein the lithography system further comprises a monitoring channel connecting the integrated metrology tool with the standalone metrology tool, and the integrated metrology tool is further configured to allocate metrology measurements between the integrated metrology tool and the standalone metrology tool and monitor the allocation and the metrology measurement with respect to specified temporal limitations of the printing tool.
• Figure 1 is a high level schematic block diagram illustration of lithography systems according to the prior art.
• Figure 2 is a high level schematic block diagram illustrating lithography systems with improved process tracking and metrology measurement analysis, according to some embodiments of the invention.
• Figures 3 and 4 are high level schematic block diagrams illustrating lithography systems with recipe optimization at the level of the integrated metrology tool, according to some embodiments of the invention.
• Figure 5 is a high level schematic block diagram illustrating of lithography systems with improved process control, according to some embodiments of the invention.
• Figure 6 is a high level schematic block diagram illustrating of lithography systems with landscape-based grouping, according to some embodiments of the invention.
• Figure 7 is a high level schematic block diagram illustrating of lithography systems with various configurations of channels disclosed above, according to some embodiments of the invention.
• Figure 8 is a high level flowchart illustrating a method, according to some embodiments of the invention. DETAILED DESCRIPTION OF THE INVENTION
• Lithography systems and methods are provided with enhanced performance based on broader utilization of the integrated metrology tool in the printing tool to handle the metrology measurements in the system in a more sophisticated and optimized way. Additional operation channels are disclosed, enabling the integrated metrology tool to monitor and/or allocate metrology measurements thereby and by a standalone metrology tool with respect to specified temporal limitations of the printing tool; to adjust and optimize the metrology measurement recipes; to provide better process control to optimize process parameters of the printing tool; as well as to group process parameters of the printing tool according to a metrology measurements landscape.
• FIG. 1 is a high level schematic block diagram illustration of lithography systems 70 according to the prior art.
• Current lithography systems 70 comprise a communication channel 115 between a printing tool 90 (e.g., a scanner, possibly a stepper, or any other printing tool) which connects a standalone metrology tool 80 to printing tool 90.
• Standalone metrology tool 80 is configured to perform metrology measurements on wafers produced by printing tool 90, e.g., to calculate corrections and provide feedback to printing tool 90, based on metrology measurements by standalone metrology tool 80.
• standalone metrology tool 80 is applied to measure several wafers per FOUP (front opening unified pod, e.g., 25 wafers) and calculate the scanner corrections required to meet the overlay budget.
• FOUP front opening unified pod, e.g., 25 wafers
• IM integrated metrology
• Integrated metrology tool 95 may be used in the prior art instead of or in addition to standalone metrology tool 80.
• Figures 2-7 are high level schematic block diagram illustrations of lithography systems 100 according to some embodiments of the invention.
• Figures 2-7 illustrate schematically multiple approaches, which may be combined in various ways to improve throughput and yield with respect to prior art lithography systems 70. Elements from Figures 2-7 may be combined in any operable combination, and the illustration of certain elements in certain figures and not in others merely serves an explanatory purpose and is non- limiting.
• One or more processor(s) 112 may be used to implement any embodiment of control module 111 (see Figure 7). It is also noted that while the disclosure relates to one standalone metrology tool and one integrated metrology tool in the printing tool, disclosed systems and methods may just as well be applied to more complex systems with multiple metrology tools and/or printing tools.
• Lithography systems 100 demonstrate several alternative and/or complementary ways to enhance performance by higher level integration and use of integrated metrology tool 95 with respect to multiple, independent and/or complementary requirements from lithography systems 100.
• Disclosed lithography systems 100 may be configured to provide improved cycle time by reducing the reaction time to process excursions as well improve process accuracy by avoiding sampling reduction which is commonly required in prior art lithography systems 70 for meeting the scanner throughput, and may result in larger errors (e.g., larger residuals and required correction).
• disclosed lithography systems 100 may increase the process yield and reduce costs.
• potentially synergetic approaches and systems are disclosed for improving the monitoring of process excursions and process variations, improving the recipe optimization, improving the overlay accuracy and improving the Correction Per Exposure (CPE) rate.
• CPE Correction Per Exposure
• FIG. 2 is a high level schematic block diagram illustrating lithography systems 100 with improved process tracking and metrology measurement analysis, according to some embodiments of the invention.
• Lithography systems 100 may be configured to have enhanced monitoring performance with respect to process excursions.
• a monitoring channel 110 may be established between a modified integrated metrology tool 105 and standalone metrology tool 80, and a control module 111 in integrated metrology tool 105 may be configured to allocate to integrated metrology tool 105 and/or to standalone metrology tool 80 and to monitor the metrology measurements and the decision and allocation process.
• a possible excursion can be detected by any of tracking the overlay, accuracy flags and/or any other parameter, by control module 111, standalone metrology tool 80 and/or any other tool.
• control module 111 may be configured to hold printing tool 90 to enable exposure for the suspected layer and decide to measure the overlay using integrated metrology tool 105, via monitoring channel 110, using standalone metrology tool 80, for performing a more extensive analysis.
• Control module 111 and/or standalone metrology tool 80 may be further configured to detect, via monitoring channel 110, process changes and adjust the metrology measurement recipe, using integrated metrology tool 105 within the scanner exposure time limitations. Therefore, monitoring channel 110 provides flexibility in the application of metrology measurement which provides both quick identification of excursion as well as means to accommodate the quality of the metrology measurements to specified scanner exposure time limitations or other requirements.
• FIGS 3 and 4 are high level schematic block diagrams illustrating lithography systems 100 with recipe optimization at the level of integrated metrology tool 105, according to some embodiments of the invention.
• integrated metrology tool 105 and/or control module 111 may be configured to perform recipe optimization and be configured to determine what scope of recipe optimization is required and to transfer, via a monitoring and optimization channel 120, more extensive recipe optimizations to standalone metrology tool 80 and/or to transfer, via an optimization channel 130, more extensive recipe optimizations to an additional metrology tool 135 or other external tools (e.g., simulation tools).
• Control module 111 may be configured to use integrated metrology tool 105 at a first phase of recipe optimization, e.g., to derive an overlay landscape as function of the wavelength and suggest optimal measurement parameters (e.g., the optimal wavelength, appetizer or other setups) - as disclosed in any of U.S. Application Publication No. 2016/0313658 and U.S. Application No. 15/329618, incorporated herein by reference in their entirety.
• the landscape relates to an at least partially continuous dependency of at least one metrology metric (e.g., overlay for the overlay landscape) on at least one recipe parameter, by simulation or in preparatory measurements.
• the derived dependency may be used to relate metrology measurements and process parameters in an analytical way or by simulation.
• the optimal measurement parameters may then by transferred to standalone metrology tool 80 via monitoring and optimization channel 120, and/or to additional metrology tool 135 via optimization channel 130 - to optimize the performance of standalone metrology tool 80, reduce cycle time and improve accuracy.
• FIG. 5 is a high level schematic block diagram illustrating of lithography systems 100 with improved process control, according to some embodiments of the invention.
• Systems 100 may comprise a process control channel 140 connecting integrated metrology tool 105 and/or control module 111 to provide input for process control software 60 (e.g., in a module which receives overlay data, optical critical dimensions (OCD) data, focus and dose data, etc. and uses the received data to improve the control over the process) and be used for improving process control outside the lithography cell.
• Possible processor(s) 112 associated with control module 111 may be configured to carry out at least part of process control software 60.
• Integrated metrology tool 105 may be configured to derive any process parameter, such as the overlay, accuracy values, and other process parameters which may be useful for process control, and provide the process parameter(s) via process control channel 140 to process control software 60 for improving process control.
• FIG. 6 is a high level schematic block diagram illustrating of lithography systems 100 with landscape-based grouping, according to some embodiments of the invention.
• Systems 100 may comprise a grouping channel 150 connecting integrated metrology tool 105 and/or control module 111 to provide input for grouping of control, which is based on landscape information.
• the grouping may be carried out by a grouping module 170, implemented externally and/or in any of integrated metrology tool 105, control module 111 and standalone metrology tool 80.
• System 100 may be configured to group control of any of wafers, chucks, processes, scanner operations, lithography or post lithography processes etc., according to metrology and/or process parameters (e.g., overlay, accuracy values or any process parameter) received through grouping channel 150 from integrated metrology tool 105 and/or control module 111; and alternatively or complementarily, received through a grouping channel 155 from standalone metrology tool 80.
• the grouping may be carried out by any processing unit, possibly even by control module 111, and may be based on any landscape information or parameter, e.g., a wavelength signature, as disclosed in any of U.S. Application Publication No. 2016/0313658 and U.S. Application No. 15/329618, incorporated herein by reference in their entirety.
• the conditions of the process tools e.g., printing tool 90
• may be modified gradually until they returns to their t 0 state. This may be achieved using feedback loop(s) between the metrology tool(s) 105, 80 and multiple process tools (e.g., printing tool 90).
• the typical fingerprint of each process tool may be learned by metrology tools 105 and/or 80, which may be configured to provide specific feedback(s) for each process tool.
• FIG. 7 is a high level schematic block diagram illustrating of lithography systems 100 with various configurations of channels 110-150 disclosed above, according to some embodiments of the invention.
• Various disclosed embodiments comprise, in addition to prior art channel 85 between printing tool 90 and standalone metrology tool 80, any of monitoring channel 110, monitoring and optimization channel 120, optimization channel 130, process control channel 140 and/or grouping channel 150 and/or 155 disclosed above. Any combination thereof may be set as a configuration of disclosed lithography systems 100.
• Figure 8 is a high level flowchart illustrating a method 200, according to some embodiments of the invention.
• the method stages may be carried out with respect to lithography systems 100 described above, which may optionally be configured to implement method 200.
• Method 200 may be at least partially implemented by at least one computer processor, e.g., in a metrology module.
• Certain embodiments comprise computer program products comprising a computer readable storage medium having computer readable program embodied therewith and configured to carry out the relevant stages of method 200.
• Method 200 may comprise the following stages, irrespective of their order.
• Method 200 may comprise monitoring (stage 210) and/or allocating (stage 220), by the integrated metrology tool of a lithography printing tool, metrology measurements by the integrated metrology tool and a standalone metrology tool with respect to specified temporal limitations of the printing tool.
• Method 200 may comprise adjusting and/or optimizing a metrology measurement recipe according to the specified temporal limitations (stage 230).
• Method 200 may further comprise optimizing process parameters of the printing tool by process control software, based on metrology measurements by at least the integrated metrology tool (stage 240).
• Method 200 may further comprise grouping process parameters of the printing tool according to a metrology measurements landscape (stage 250).
• Method 200 may further comprise deriving the metrology measurements landscape by at least the integrated metrology tool (stage 260).
• These computer program instructions may also be stored in a computer readable medium that can direct a computer, other programmable data processing apparatus, or other devices to function in a particular manner, such that the instructions stored in the computer readable medium produce an article of manufacture including instructions which implement the function/act specified in the flowchart and/or portion diagram or portions thereof.
• the computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other devices to cause a series of operational steps to be performed on the computer, other programmable apparatus or other devices to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide processes for implementing the functions/acts specified in the flowchart and/or portion diagram or portions thereof.
• each portion in the flowchart or portion diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s).
• the functions noted in the portion may occur out of the order noted in the figures. For example, two portions shown in succession may, in fact, be executed substantially concurrently, or the portions may sometimes be executed in the reverse order, depending upon the functionality involved.
• each portion of the portion diagrams and/or flowchart illustration, and combinations of portions in the portion diagrams and/or flowchart illustration can be implemented by special purpose hardware -based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.
• an embodiment is an example or implementation of the invention.
• the various appearances of "one embodiment”, “an embodiment”, “certain embodiments” or “some embodiments” do not necessarily all refer to the same embodiments.
• various features of the invention may be described in the context of a single embodiment, the features may also be provided separately or in any suitable combination.
• the invention may also be implemented in a single embodiment.
• Certain embodiments of the invention may include features from different embodiments disclosed above, and certain embodiments may incorporate elements from other embodiments disclosed above.
• the disclosure of elements of the invention in the context of a specific embodiment is not to be taken as limiting their use in the specific embodiment alone.

Landscapes

• Physics & Mathematics (AREA)
• General Physics & Mathematics (AREA)
• Engineering & Computer Science (AREA)
• Computer Networks & Wireless Communication (AREA)
• Health & Medical Sciences (AREA)
• Environmental & Geological Engineering (AREA)
• Epidemiology (AREA)
• Public Health (AREA)
• Exposure And Positioning Against Photoresist Photosensitive Materials (AREA)
• Exposure Of Semiconductors, Excluding Electron Or Ion Beam Exposure (AREA)
• Slot Machines And Peripheral Devices (AREA)

Priority Applications (6)

Applications Claiming Priority (2)

Publications (1)

Family

ID=62109931

Family Applications (1)

Country Status (7)

Citations (5)

Family Cites Families (10)

• 2017
  • 2017-08-21 JP JP2019524952A patent/JP6877541B2/ja active Active
  • 2017-08-21 KR KR1020197016915A patent/KR102271217B1/ko active Active
  • 2017-08-21 WO PCT/US2017/047742 patent/WO2018089076A1/en not_active Ceased
  • 2017-08-21 CN CN201780069251.7A patent/CN109923480B/zh active Active
  • 2017-08-21 US US15/568,304 patent/US10331050B2/en active Active
  • 2017-08-21 SG SG11201903730XA patent/SG11201903730XA/en unknown
  • 2017-11-13 TW TW106139082A patent/TWI791470B/zh active

Patent Citations (5)

Also Published As

Similar Documents

Legal Events