Patents by Inventor Haihua Mu
Haihua Mu has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
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Patent number: 10532832Abstract: A magnetic levitation reaction sphere includes a spherical-housing-shaped rotor and three groups of stators. Each group includes two stators using the sphere center of the rotor as a symcenter. Axes of the three groups are mutually orthogonal. Each stator comprises a stator core and a coil array. An air gap is reserved between an inner surface of each stator core and the outer surface of the rotor. Through grooves are radially formed in the stator cores. The coil arrays are disc-type motor stator windings. Two effective sides of each coil in each coil array are respectively placed in two through grooves of the corresponding stator core. The magnetic levitation reaction sphere has low cost; levitation and rotation driving are integrated; the magnetic levitation reaction sphere has a simple and compact structure, a small size and a low mass, and relates to inherent stable levitation; and the levitation control is simple.Type: GrantFiled: March 15, 2016Date of Patent: January 14, 2020Assignees: TSINGHUA UNIVERSITY, BEIJING U-PRECISION TECH CO., LTD.Inventors: Ming Zhang, Yu Zhu, Anlin Chen, Kaiming Yang, Rong Cheng, Feng Liu, Jinchun Hu, Chuxiong Hu, Dengfeng Xu, Haihua Mu
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Publication number: 20180170581Abstract: A magnetic levitation reaction sphere includes a spherical-housing-shaped rotor and three groups of stators. Each group includes two stators using the sphere center of the rotor as a symcenter. Axes of the three groups are mutually orthogonal. Each stator comprises a stator core and a coil array. An air gap is reserved between an inner surface of each stator core and the outer surface of the rotor. Through grooves are radially formed in the stator cores. The coil arrays are disc-type motor stator windings. Two effective sides of each coil in each coil array are respectively placed in two through grooves of the corresponding stator core. The magnetic levitation reaction sphere has low cost; levitation and rotation driving are integrated; the magnetic levitation reaction sphere has a simple and compact structure, a small size and a low mass, and relates to inherent stable levitation; and the levitation control is simple.Type: ApplicationFiled: March 15, 2016Publication date: June 21, 2018Inventors: Ming ZHANG, Yu ZHU, Anlin CHEN, Kaiming YANG, Rong CHENG, Feng LIU, Jinchun HU, Chuxiong HU, Dengfeng XU, Haihua MU
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Patent number: 9995569Abstract: A six-degree-of-freedom displacement measurement method for an exposure region on a wafer stage, the wafer stage comprises a coil array and a movable platform. A planar grating is fixed below a permanent magnet array of the movable platform. A reading head is fixed in a gap of the coil array. A measurement region is formed on the planar grating by an incident measurement light beam of the reading head. The reading head measures the six-degree-of-freedom displacement of the measurement region, so that the six-degree-of-freedom displacement of the exposure region is obtained through calculation. In the method, the six-degree-of-freedom displacement of the exposure region at any time is measured; the measurement complexity is reduced and the measurement precision is improved, and especially, the six-degree-of-freedom displacement of the exposure region can be precisely measured at any time even if the movable platform has high flexibility.Type: GrantFiled: March 15, 2016Date of Patent: June 12, 2018Assignees: TSINGHUA UNIVERSITY, BEIJING U-PRECISION TECH CO., LTD.Inventors: Yu Zhu, Ming Zhang, Anlin Chen, Rong Cheng, Kaiming Yang, Feng Liu, Yujing Song, Fan Zhi, Jinchun Hu, Dengfeng Xu, Haihua Mu, Chuxiong Hu
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Publication number: 20180080757Abstract: A six-degree-of-freedom displacement measurement method for an exposure region on a wafer stage, the wafer stage comprises a coil array and a movable platform. A planar grating is fixed below a permanent magnet array of the movable platform. A reading head is fixed in a gap of the coil array. A measurement region is formed on the planar grating by an incident measurement light beam of the reading head. The reading head measures the six-degree-of-freedom displacement of the measurement region, so that the six-degree-of-freedom displacement of the exposure region is obtained through calculation. In the method, the six-degree-of-freedom displacement of the exposure region at any time is measured; the measurement complexity is reduced and the measurement precision is improved, and especially, the six-degree-of-freedom displacement of the exposure region can be precisely measured at any time even if the movable platform has high flexibility.Type: ApplicationFiled: March 15, 2016Publication date: March 22, 2018Inventors: Yu Zhu, Ming Zhang, Anlin Chen, Rong Cheng, Kaiming Yang, Feng Liu, Yujing Song, Fan Zhi, Jinchun Hu, Dengfeng Xu, Haihua Mu, Chuxiong Hu
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Patent number: 9903704Abstract: A three-DOF (Degree of Freedom) heterodyne grating interferometer displacement measurement system comprises a dual-frequency laser, a grating interferometer, a measurement grating, receivers and an electronic signal processing component; the grating interferometer comprises a polarizing beam splitter, a reference grating and dioptric elements; the measurement system realizes displacement measurement on the basis of grating diffraction, the optical Doppler Effect and the optical beat frequency principle. Three linear displacements can be output by the system when the grating interferometer and the measurement grating perform a three-DOF linear relative motion. The measurement system can reach sub-nanometer and higher resolution and precision, and can simultaneously measure three linear displacements.Type: GrantFiled: June 5, 2014Date of Patent: February 27, 2018Assignee: TSINGHUA UNIVERSITYInventors: Yu Zhu, Leijie Wang, Ming Zhang, Zhao Liu, Rong Cheng, Kaiming Yang, Dengfeng Xu, Weinan Ye, Li Zhang, Yanpo Zhao, Huichao Qin, Li Tian, Jin Zhang, Wensheng Yin, Haihua Mu, Jinchun Hu
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Patent number: 9904183Abstract: A coarse motion and fine motion integrated reticle stage driven by a planar motor comprises a movable platform (100) of the reticle stage, a balance mass (200), a drive motor, a mask plate (101, 102), a base (001), a vibration isolation system (500), and a measuring system, wherein, the vibration isolation system is located between the balance mass and the base, and the mask plate is mounted on the movable platform. The drive motor of the movable platform is a moving-iron type planar motor (300). The reticle stage can lower the design complexity of the drive motor of the movable platform. Compared with a linear motor, the planar motor can provide push forces in more directions, the number of motors is reduced, the structure of the movable platform is more compact, the inherent frequency and the control bandwidth of the movable platform are improved, and thus control precision is improved.Type: GrantFiled: April 17, 2015Date of Patent: February 27, 2018Assignees: TSINGHUA UNIVERSITY, BEIJING U-PRECISION TECH CO., LTD.Inventors: Yu Zhu, Ming Zhang, Fan Zhi, Zhao Liu, Rong Cheng, Kaiming Yang, Li Zhang, Huichao Qin, Yanpo Zhao, Li Tian, Weinan Ye, Jin Zhang, Wensheng Yin, Haihua Mu, Jinchun Hu
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Patent number: 9885556Abstract: A dual-frequency grating interferometer displacement measurement system, comprises a dual-frequency laser, an interferometer, a measurement grating and an electronic signal processing component. The measurement system realizes displacement measurement based on grating diffraction, optical Doppler effect and optical beat frequency theory. Dual-frequency laser light is emitted from the dual-frequency laser and split into reference light and measurement light via a polarization spectroscope. The measurement light is incident to the measurement grating to generate positive and negative first-order diffraction. The diffraction light and the reference light form a beat frequency signal containing displacement information about two directions at a photo-detection unit, and linear displacement output is realized after signal processing.Type: GrantFiled: October 28, 2013Date of Patent: February 6, 2018Assignee: TSINGHUA UNIVERSITYInventors: Yu Zhu, Ming Zhang, Leijie Wang, Jinchun Hu, Longmin Chen, Kaiming Yang, Dengfeng Xu, Wensheng Yin, Haihua Mu
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Patent number: 9879979Abstract: A displacement measurement system of heterodyne grating interferometer, comprises a reading head, a measurement grating and an electronic signal processing component. Laser light emitted from the laser tube is collimated, passes through the first polarization spectroscope, and then emits two light beams with an orthogonal polarization direction and an orthogonal propagation direction; the two light beams pass through two acousto-optic modulators and respectively generate two first-order diffraction light beams with different frequencies, which are later divided into reference light and measurement light; two parallel reference light beams form a beat frequency electric signal with positive and negative first-order diffraction measurement light respectively after passing through a measurement signal photo-electric conversion unit; the beat frequency signals are transmitted to the electronic signal processing component for signal processing, thus the output of linear displacement in two directions is realized.Type: GrantFiled: October 28, 2013Date of Patent: January 30, 2018Assignee: TSINGHUA UNIVERSITYInventors: Ming Zhang, Yu Zhu, Leijie Wang, Jinchun Hu, Longmin Chen, Kaiming Yang, Dengfeng Xu, Wensheng Yin, Haihua Mu
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Patent number: 9869857Abstract: An optical grating phase modulator for a laser interference photoetching system is composed of a substrate, an optical grating, an electric motor and an optical grating positioner. The optical grating, the electric motor and the optical grating positioner are all mounted on the substrate. The optical grating is circular or rectangular, and adopt transmission or reflection type optical grating. A light beam is incident on the optical grating and generates diffraction, and when the electric motor drives the optical grating to continuously move relative to the incident light beam, diffracted light will generate a frequency shift, thereby realizing the phase modulation of the light beam. The optical grating phase modulator has the advantages of high phase modulation speed, high regulation precision and wide regulation range, thereby improving the whole performance of an interference photoetching system.Type: GrantFiled: January 13, 2014Date of Patent: January 16, 2018Assignee: Tsinghua UniversityInventors: Yu Zhu, Ming Zhang, Leijie Wang, Rong Cheng, Kaiming Yang, Zhao Liu, Jinchun Hu, Wensheng Yin, Haihua Mu, Chuxiong Hu, Dengfeng Xu
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Magnetically suspended coarse motion and fine motion integrated reticle stage driven by planar motor
Patent number: 9791789Abstract: A magnetically suspended coarse motion and fine motion integrated reticle stage driven by a planar motor comprises a movable platform (100), a balance mass (200), a drive motor, a mask plate (101), a base (001), a vibration isolation system (500), and a measuring system, wherein, the vibration isolation system is located between the balance mass and the base, and the mask plate is mounted on the movable platform. The drive motor of the movable platform is a moving-iron type planar motor (300). The reticle stage can lower the design complexity of the drive motor of the movable platform. Compared with a linear motor, the planar motor can provide push forces in more directions, the number of motors is reduced, the structure of the movable platform is more compact, the inherent frequency and the control bandwidth of the movable platform are improved, and thus control precision is improved.Type: GrantFiled: April 17, 2015Date of Patent: October 17, 2017Assignees: TSINGHUA UNIVERSITY, BEIJING U-PRECISION TECH CO., LTD.Inventors: Ming Zhang, Yu Zhu, Fan Zhi, Rong Cheng, Kaiming Yang, Zhao Liu, Li Zhang, Huichao Qin, Yanpo Zhao, Li Tian, Weinan Ye, Jin Zhang, Wensheng Yin, Haihua Mu, Jinchun Hu -
Patent number: 9766054Abstract: A planar motor rotor displacement measuring device and its measuring method are provided. The motor is a moving-coil type planar motor. The device comprises probes, two sets of sine sensors, two sets of cosine sensors, a signal lead wire and a signal processing circuit. The method is arranging two sets of magnetic flux density sensors within a magnetic field pitch ? along two vertical movement directions in the rotor located in the sine magnetic field area. Sampled signals of the four sets of sensors are respectively processed with a frequency multiplication operation, four subdivision signals are obtained, the zero-crossing points of the four subdivision signals are detected, and then two sets of orthogonal pulse signals are generated. The pulse number of the orthogonal pulse signals is counted, and phase difference of the two sets of orthogonal pulse signals is respectively detected.Type: GrantFiled: February 8, 2013Date of Patent: September 19, 2017Assignees: SHANGHAI MICRO ELECTRONICS EQUIPMENT CO., LTD., TSINGHUA UNIVERSITYInventors: Jinchun Hu, Yu Zhu, Wensheng Yin, Longmin Chen, Kaiming Yang, Ming Zhang, Dengfeng Xu, Haihua Mu, Chuxiong Hu, Zhao Liu
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Patent number: 9752643Abstract: A negative stiffness system for gravity compensation of a micropositioner of wafer table in lithography machine, characterized in that, the negative stiffness system includes at least three sets of quasi-zero stiffness units, each of the sets of quasi-zero stiffness units comprises a pair of negative stiffness springs and a positive stiffness spring, the positive stiffness spring is vertically positioned, the pair of negative stiffness springs are obliquely and symmetrically positioned at two sides of the positive stiffness spring, upper ends of the negative stiffness springs and the positive stiffness spring are connected together and fixed to the bottom surface of a rotor of the micropositioner, and lower ends of the negative stiffness springs and the positive stiffness spring are connected to a base, respectively. The system reduces the stiffness in vertical direction and prevents the influence of permanent magnet on its surroundings, while improving the bearing capacity.Type: GrantFiled: December 6, 2013Date of Patent: September 5, 2017Assignees: SHANGHAI MICRO ELECTRONICS EQUIPMENT CO., LTD., TSINGHUA UNIVERSITYInventors: Yu Zhu, Ming Zhang, Zhao Liu, Rong Cheng, Jing Wang, Li Tian, Dengfeng Xu, Kaiming Yang, Jinchun Hu, Wensheng Yin, Haihua Mu, Hao Liu, Chuxiong Hu
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Publication number: 20170115580Abstract: A coarse motion and fine motion integrated reticle stage driven by a planar motor comprises a movable platform (100) of the reticle stage, a balance mass (200), a drive motor, a mask plate (101, 102), a base (001), a vibration isolation system (500), and a measuring system, wherein, the vibration isolation system is located between the balance mass and the base, and the mask plate is mounted on the movable platform. The drive motor of the movable platform is a moving-iron type planar motor (300). The reticle stage can lower the design complexity of the drive motor of the movable platform. Compared with a linear motor, the planar motor can provide push forces in more directions, the number of motors is reduced, the structure of the movable platform is more compact, the inherent frequency and the control bandwidth of the movable platform are improved, and thus control precision is improved.Type: ApplicationFiled: April 17, 2015Publication date: April 27, 2017Inventors: Yu ZHU, Ming ZHANG, Fan ZHI, Zhao LIU, Rong CHENG, Kaiming YANG, Li ZHANG, Huichao QIN, Yanpo ZHAO, Li TIAN, Weinan YE, Jin ZHANG, Wensheng YIN, Haihua MU, Jinchun HU
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MAGNETICALLY SUSPENDED COARSE MOTION AND FINE MOTION INTEGRATED RETICLE STAGE DRIVEN BY PLANAR MOTOR
Publication number: 20170052461Abstract: A magnetically suspended coarse motion and fine motion integrated reticle stage driven by a planar motor comprises a movable platform (100), a balance mass (200), a drive motor, a mask plate (101), a base (001), a vibration isolation system (500), and a measuring system, wherein, the vibration isolation system is located between the balance mass and the base, and the mask plate is mounted on the movable platform. The drive motor of the movable platform is a moving-iron type planar motor (300). The reticle stage can lower the design complexity of the drive motor of the movable platform. Compared with a linear motor, the planar motor can provide push forces in more directions, the number of motors is reduced, the structure of the movable platform is more compact, the inherent frequency and the control bandwidth of the movable platform are improved, and thus control precision is improved.Type: ApplicationFiled: April 17, 2015Publication date: February 23, 2017Inventors: Ming ZHANG, Yu ZHU, Fan ZHI, Rong CHENG, Kaiming YANG, Zhao LIU, Li ZHANG, Huichao QIN, Yanpo ZHAO, Li TIAN, Weinan YE, Jin ZHANG, Wensheng YIN, Haihua MU, Jinchun HU -
Publication number: 20160153764Abstract: A three-DOF (Degree of Freedom) heterodyne grating interferometer displacement measurement system comprises a dual-frequency laser, a grating interferometer, a measurement grating, receivers and an electronic signal processing component; the grating interferometer comprises a polarizing spectroscope, a reference grating and dioptric elements; the measurement system realizes displacement measurement on the basis of grating diffraction, the optical Doppler Effect and the optical beat frequency principle. Three linear displacements can be output by the system when the grating interferometer and the measurement grating perform a three-DOF linear relative motion. The measurement system can reach sub-nanometer and even higher resolution and precision, and can simultaneously measure three linear displacements. The measurement system has the advantages of being environmentally insensitive, high in measurement precision, small in size, light in weight, etc.Type: ApplicationFiled: June 5, 2014Publication date: June 2, 2016Inventors: Yu ZHU, Leijie WANG, Ming ZHANG, Zhao LIU, Rong CHENG, Kaiming YANG, Dengfeng XU, Weinan YE, Li ZHANG, Yanpo ZHAO, Huichao QIN, Li TIAN, Jin ZHANG, Wensheng YIN, Haihua MU, Jinchun HU
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Publication number: 20160138903Abstract: A two-DOF heterodyne grating interferometer displacement measurement system, comprising a dual-frequency laser, a grating interferometer, a measurement grating, receivers and an electronic signal processing component, wherein the grating interferometer comprises a polarizing spectroscope, a reference grating and dioptric elements. The measurement system achieves the displacement measurement on the basis of the grating diffraction, the optical Doppler effect and the optical beat frequency principle. When the grating interferometer and the measurement grating conduct two-DOF linear relative motion, the system can output two linear displacements. The measurement system can achieve sub-nanometer or even higher resolution and accuracy, and can simultaneously measure two linear displacements.Type: ApplicationFiled: June 5, 2014Publication date: May 19, 2016Applicant: TSINGHUA UNIVERSITYInventors: Ming ZHANG, Yu ZHU, Leijie WANG, Kaiming YANG, Zhao LIU, Rong CHENG, Hao LIU, Dengfeng XU, Weinan YE, Li ZHANG, Yanpo ZHAO, Li TIAN, Jin ZHANG, Jinchun HU, Haihua MU, Wensheng YIN, Huichao QIN
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Patent number: 9310797Abstract: A single degree of freedom vibration isolating device of a linear motor and a motion control method thereof. The vibration isolating device comprises a balance block, an anti-drifting driving unit, and a control unit. An upper surface of the balance block is connected to a stator of the linear motor, and a lower surface of the balance block is connected to a base. The anti-drifting driving unit is connected to the balance block for controlling the position of the balance block. Provided two motion control methods: inputting a second grating ruler signal to the control unit as feedback to perform variable stiffness and nonlinear control on the balance block; inputting a first and a second grating ruler signal to the control unit as feedback to obtain resultant centroid displacement signals of the rotor and the balance block to perform nonlinear anti-drifting control on the balance block.Type: GrantFiled: April 15, 2013Date of Patent: April 12, 2016Assignee: TSINGHUA UNIVERSITYInventors: Kaiming Yang, Yu Zhu, Dongdong Yu, Rong Cheng, Ming Zhang, Xin Li, Haihua Mu, Jinchun Hu, Dengfeng Xu, Wensheng Yin, Guofeng Ji
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Patent number: 9310782Abstract: A method for measuring the displacement of a planar motor rotor. The measuring method comprises: four magnetic induction intensity sensors are distributed on the planar motor rotor; sampled signals of the four distributed sensors are processed to obtain signals Bsx, Bcx, Bsy and Bcy and magnetic field reference values Bksx, Bkcx, Bksy and Bkcy; and X-direction displacement and Y-direction displacement can be measured respectively according to inequalities (I) and (II) by judgments, wherein ?x and ?y are X-direction displacement resolution and Y-direction displacement resolution respectively, and BM is the magnetic induction intensity amplitude of the magnetic field of said planar motor. The method provided by the invention is simple in calculation, can avoid calculation of a transcendental function and solve the quadrant judgment problem, is favorable to real-time high-speed operation and has a high engineering value.Type: GrantFiled: February 21, 2013Date of Patent: April 12, 2016Assignees: SHANGHAI MICRO ELECTRONICS EQUIPMENT CO., LTD., TSINGHUA UNIVERSITYInventors: Yu Zhu, Jinchun Hu, Dengfeng Xu, Yuting Sun, Wensheng Yin, Ming Zhang, Kaiming Yang, Haihua Mu
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Publication number: 20150369331Abstract: A negative stiffness system for gravity compensation of a micropositioner of wafer table in lithography machine, characterized in that, the negative stiffness system includes at least three sets of quasi-zero stiffness units, each of the sets of quasi-zero stiffness units comprises a pair of negative stiffness springs and a positive stiffness spring, the positive stiffness spring is vertically positioned, the pair of negative stiffness springs are obliquely and symmetrically positioned at two sides of the positive stiffness spring, upper ends 20 of the negative stiffness springs and the positive stiffness spring are connected together and fixed to the bottom surface of a rotor of the micropositioner, and lower ends of the negative stiffness springs and the positive stiffness spring are connected to a base, respectively. The system reduces the stiffness in vertical direction and prevents the influence of permanent magnet on its surroundings, while improving the bearing capacity.Type: ApplicationFiled: December 6, 2013Publication date: December 24, 2015Applicants: SHANGHAI MICRO ELECTRONICS EQUIPMENT CO., LTD., TSINGHUA UNIVERSITYInventors: Yu ZHU, Ming ZHANG, Zhao LIU, Rong CHENG, Jing WANG, Li TIAN, Dengfeng XU, Kaiming YANG, Jinchun HU, Wensheng YIN, Haihua MU, Hao LIU, Chuxiong HU
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Publication number: 20150362723Abstract: An optical grating phase modulator for a laser interference photoetching system is composed of a substrate, an optical grating, an electric motor and an optical grating positioner. The optical grating, the electric motor and the optical grating positioner are all mounted on the substrate. The optical grating is circular or rectangular, and adopt transmission or reflection type optical grating. A light beam is incident on the optical grating and generates diffraction, and when the electric motor drives the optical grating to continuously move relative to the incident light beam, diffracted light will generate a frequency shift, thereby realizing the phase modulation of the light beam. The optical grating phase modulator has the advantages of high phase modulation speed, high regulation precision and wide regulation range, thereby improving the whole performance of an interference photoetching system.Type: ApplicationFiled: January 13, 2014Publication date: December 17, 2015Applicant: Tsinghua UniversityInventors: Yu Zhu, Ming Zhang, Leijie Wang, Rong Cheng, Kaiming Yang, Zhao Liu, Jinchun Hu, Wensheng Yin, Haihua MU, Chuxiong Hu, Dengfeng Xu