Abstract: 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 a vertical polarization direction and a vertical 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.

Abstract: A maglev working table with six degrees of freedom comprises a pedestal (800), a rotation drive apparatus, a planar-motion apparatus, an angle measuring apparatus (500), and a displacement measuring apparatus. The displacement measuring apparatus comprises four direct-current motors (600) and four displacement measuring apparatus PSD assemblies. Under the effect of the rotation drive apparatus, a planar-motion apparatus coil array stator (200) axially connected to a rotation drive apparatus circular permanent-magnet array mover (300) rotates, so that a phase difference is formed between a planar-motion apparatus permanent-magnet array mover (100) and the planar-motion apparatus coil array stator, and then the maglev working table mover, namely, the planar-motion apparatus permanent-magnet array mover rotates at 360° in the horizontal plane.

Abstract: A method for measuring displacement of a large-range moving platform, comprising: arranging multiple beams of first measuring light parallel to one another and generated by an optical path distribution device and a position sensitive detector array in a certain manner, to ensure that at least one beam of first measuring light is detected by the position sensitive detector array when a moving platform is at any position of a moving area; a detection head array capable of determining whether a light beam is shaded being used for auxiliary measurement of a position of the moving platform; and determining a position of the moving platform that corresponds to the first measuring light measured by the position sensitive detector array, to calculate displacement of the moving platform. The method effectively enlarges a measurement range of the position sensitive detector array, and implements measurement of long range displacement of the moving platform.

Abstract: A silicon wafer platform with anti-collision function comprises a silicon wafer platform body (1) and a cable platform (2). The cable platform (2) is mounted on one side of the silicon wafer platform. The silicon wafer platform comprises three airbags (3), four damping buffer elements (4) and an air source (6), the three airbags (3) being connected in series and respectively secured on the other three sides of the silicon wafer platform by an airbag support (5), two adjacent airbags (3) communicating with a gas pipeline by one damping buffer element (4), and the gas pipeline being secured on the cable platform (2) and communicating with the air source. When two silicon platforms collide, the collision is buffered by the airbags and the silicon wafer platforms are not bounced off.

Abstract: 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.

Abstract: A dual wafer stage exchanging system for a lithographic device is disclosed, said system comprises two wafer stages running between an exposure workstation and a pre-processing workstation, and said two stages are set on a base and suspended above the upper surface of the base by air bearings. Each wafer stages is passed through by a Y-direction guide rail respectively, wherein one end of said guide rail is connected with a main driving unit and another end of said guide rail is detachably coupled with one of the two X-direction auxiliary driving units with single degree of freedom, and said two wafer stages are capable of moving in Y-direction along the guide rails and moving in X-direction under the drive of the auxiliary driving units with single degree of freedom. The position exchange of said two wafer stages can be enabled by the detachment and connection of the Y-direction guide rails and the auxiliary units with single degree of freedom.

Abstract: 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.

Abstract: A method for measuring displacement of a large-range moving platform, comprising: arranging multiple beams of first measuring light parallel to one another and generated by an optical path distribution device and a position sensitive detector array in a certain manner, to ensure that at least one beam of first measuring light is detected by the position sensitive detector array when a moving platform is at any position of a moving area; a detection head array capable of determining whether a light beam is shaded being used for auxiliary measurement of a position of the moving platform; and determining a position of the moving platform that corresponds to the first measuring light measured by the position sensitive detector array, to calculate displacement of the moving platform. The method effectively enlarges a measurement range of the position sensitive detector array, and implements measurement of long range displacement of the moving platform.

Abstract: 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.

Abstract: A two-dimensional, position-sensitive sensor-based system for positioning an object having six degrees of freedom in space, used for positioning of a silicon table and mask table of a lithography machine. The system comprises mainly a semiconductor laser 1, an optical fiber collimator 2, optical fibers 3, 7, 10, and 13, an optical fiber splitter 4, filter plates 6, 9, and 12, three PSD sensors 5, 8, and 11, and a signal processing system. Laser emitted by the semiconductor laser 1 is irradiated onto the optical fiber collimator 2, then transmitted respectively via three paths, and received by the PSD sensors 5, 8, and 11 after having background light filtered out by the filter plates 6, 9, and 12, while the positions of laser spots on the three PSD sensors 5, 8, and 11 are processed by the signal processing system to acquire the position and orientation.

Abstract: 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.

Abstract: A dual-stage exchange system for a lithographic apparatus comprises a silicon chip stage (13) operating in an exposure workstation (3) and a silicon chip (14) stage operating in a pre-processing workstation (4). The two silicon chip stages (13, 14) are provided on the same base stage (1), and suspended on an upper surface (2) of the base stage by air bearings. The two silicon chip stages (13, 14) can move along guide rails (15, 16) in the Y direction. One end of each guide rail (15, 16) is connected to a main driving unit (11, 12), and the other end of each guide rail (15, 16) is butt-jointed with an X-direction single-freedom auxiliary driving unit (7, 8). The silicon chip stages (13, 14) are driven by the single-freedom auxiliary driving units (7, 8) cooperated with the main driving units (11, 12) to move along the X direction.

Abstract: A dual-stage exchange system for a lithographic apparatus comprises a silicon chip stage (10) operating in an exposure workstation (6) and a silicon chip stage (12) operating in a pre-processing workstation (7). Each silicon chip stage (10, 12) is supported by a six-freedom micro-motion stage, respectively. The silicon chip stage (10, 12) and the six-freedom micro-motion stage form a silicon chip stage group. The two silicon chip stage groups are provided on the same rectangular base stage (1) and suspended on an upper surface (2) of the base sage by air bearings. A double-freedom driving unit (21a, 21b, 22a, 22b) is provided on each edge of the base stage (1), respectively. The six-freedom micro-motion stage of the silicon chip stage group has an upper layer driver and a lower layer driver, capable of achieving six-freedom control.

Abstract: A two-dimensional, position-sensitive sensor-based system for positioning an object having six degrees of freedom in space, used for positioning of a silicon table and mask table of a lithography machine. The system comprises mainly a semiconductor laser 1, an optical fiber collimator 2, optical fibers 3, 7, 10, and 13, an optical fiber splitter 4, filter plates 6, 9, and 12, three PSD sensors 5, 8, and 11, and a signal processing system. Laser emitted by the semiconductor laser 1 is irradiated onto the optical fiber collimator 2, then transmitted respectively via three paths, and received by the PSD sensors 5, 8, and 11 after having background light filtered out by the filter plates 6, 9, and 12, while the positions of laser spots on the three PSD sensors 5, 8, and 11 are processed by the signal processing system to acquire the position and orientation.

Abstract: A nanometer precision six-DOF magnetic suspension micro-stage and the application thereof are provided which are mainly used in semiconductor photolithography devices. The micro-stage includes a cross support and four two-DOF actuators. Each 2-DOF actuator comprises a vertically polarized permanent magnet, a horizontal force coil and a vertical force coil; the permanent magnet being mounted on an end of the cross support, the horizontal force coil and the vertical force coil being arranged on a side of and below the permanent magnet respectively and being spaced apart from the permanent magnet; the cross support and four vertically polarized permanent magnets constitute a mover of the micro-stage; the horizontal force coil and the vertical force coil being fixed by a coil framework respectively and constituting a stator of the micro-stage; and the stator being mounted on a base of the micro-stage.

Abstract: A nanometer precision six-DOF magnetic suspension micro-stage and the application thereof are provided which are mainly used in semiconductor photolithography devices. The micro-stage includes a cross support and four two-DOF actuators. Each 2-DOF actuator comprises a vertically polarized permanent magnet, a horizontal force coil and a vertical force coil; the permanent magnet being mounted on an end of the cross support, the horizontal force coil and the vertical force coil being arranged on a side of and below the permanent magnet respectively and being spaced apart from the permanent magnet; the cross support and four vertically polarized permanent magnets constitute a mover of the micro-stage; the horizontal force coil and the vertical force coil being fixed by a coil framework respectively and constituting a stator of the micro-stage; and the stator being mounted on a base of the micro-stage.

Abstract: A two-dimensional locating method of a motion platform based on a magnetic steel array involves the following steps: placing more than four linear Hall sensors at any different positions within one or more polar distances of the magnetic steel array on the surface of the motion platform in a motion system; determining a magnetic flux density distribution model according to the magnetic steel array; determining the mounting positions of the above-mentioned linear Hall sensors, which are converted into phases with respect to the mass center of the motion platform; recording the magnetic flux density measured values of the linear Hall sensors as the motion proceeds; solving the phases of the mass center of the motion platform in a plane, with the measured values being served as observed quantities and the magnetic flux density distribution model being served as a computation model; and determining the position of the mass center of the motion platform with respect to an initial phase according to the phase, so a

Abstract: A dual-stage switching system for lithographic machine includes a wafer stage to be operated in an exposure station and another wafer stage to be operated in a pre-processing station. The two wafer stages are provided on a base, with four 2-DOF driving units capable of moving along X direction and Y direction being provided along the edge of the base, and the wafer stages being disposed in a space surrounded by the four 2-DOF driving units and suspended on an upper surface of the base by air bearings. Each of the 2-DOF driving units includes upper and lower linear guides and a guiding sleeve, with the upper and lower linear guides being installed vertical to each other in their corresponding guiding sleeve. Two adjacent 2-DOF driving units cooperatively drive the wafer stage) to move in the X direction and Y direction.

Abstract: A dual wafer stage exchanging system for a lithographic device is disclosed, said system comprises two wafer stages running between an exposure workstation and a pre-processing workstation, and said two stages are set on a base and suspended above the upper surface of the base by air bearings. Each wafer stages is passed through by a Y-direction guide rail respectively, wherein one end of said guide rail is connected with a main driving unit and another end of said guide rail is detachably coupled with one of the two X-direction auxiliary driving units with single degree of freedom, and said two wafer stages are capable of moving in Y-direction along the guide rails and moving in X-direction under the drive of the auxiliary driving units with single degree of freedom. The position exchange of said two wafer stages can be enabled by the detachment and connection of the Y-direction guide rails and the auxiliary units with single degree of freedom.

Abstract: A dual-stage exchange system for a lithographic apparatus comprises a silicon chip stage (10) operating in an exposure workstation (6) and a silicon chip stage (12) operating in a pre-processing workstation (7). Each silicon chip stage (10, 12) is supported by a six-freedom micro-motion stage, respectively. The silicon chip stage (10, 12) and the six-freedom micro-motion stage form a silicon chip stage group. The two silicon chip stage groups are provided on the same rectangular base stage (1) and suspended on an upper surface (2) of the base sage by air bearings. A double-freedom driving unit (21a, 21b, 22a, 22b) is provided on each edge of the base stage (1), respectively. The six-freedom micro-motion stage of the silicon chip stage group has an upper layer driver and a lower layer driver, capable of achieving six-freedom control.