Abstract: Method and arrangement for oscillation isolation by means of an air bearing. The electropneumatic valves (4) for the compressed-air supply to the air bearing are subjected to a dither signal. This causes additional vibration of the mass 1 to be isolated. A compensation signal transmitter (12) ensures that additional vibration of the mass (1) is suppressed, by controlling actuators (10). Overall, hysteresis effects are avoided in the control of the compressed-air flow.

Abstract: The invention relates to a device for compensating for magnetic fields which has two sensors which are active in different frequency ranges and thus allows regulation with a bandwidth from 0 to 20 kHz.

Abstract: The invention relates to an active vibration isolation system in which the effective axis of a sensor essentially corresponds to the effective axis of an actuator and the sensor and the actuator are arranged close to one another.

Abstract: The invention relates to an active vibration isolation system in which at least one sensor is provided for detection of ground vibration, and the system has a control device which calculates compensation signals in at least two degrees of freedom, based on movements of the ground.

Abstract: The invention relates to a vibration isolation system, comprising at least one fluid bearing having a first control device in order to control the fluid pressure and having at least one actuator in order to compensate for position changes of the load to be isolated, which actuator is controlled by at least one second control device, wherein the input of one control device is connected to the output of the other control device.

Abstract: A magnetic spring device with negative stiffness contains at least one first pole body combination composed of at least one first, at least one second and at least one third pole body, which each have opposite magnetic poles, with the pole bodies in the combination being aligned such that opposite poles are opposite one another and the first and the third pole bodies assume a defined distance from one another, in which the second pole body is arranged, with the pole bodies being arranged such that they can move relative to one another.

Abstract: The invention relates to an active vibration isolation system which detects structural vibration of the mass to be isolated via a sensor and also takes account of these disturbance variables.

Abstract: The invention relates to the control and regulation of a vibration isolation system with a number of vibration signal transducers for providing analogue sensor signals and a number of actuators for suppressing vibrations by processing the sensor signals to form actuator actuation signals for driving the actuators. One object of the invention is to demonstrate a way which enables high-quality parameterizability and regulating performance over a considerably wider frequency bandwidth of a vibration isolation system to be regulated. The invention proposes digitizing some of the sensor signals provided and processing them to form digital actuator actuation signals and processing other sensor signals provided in an analogue manner to form analogue actuator actuation signals and combining the digital actuator actuation signals and the analogue actuator actuation signals to form common actuator actuation signals which are supplied to the actuators in order to drive them.

Abstract: There is provided a method and an apparatus for isolating mechanical vibrations reacting to beam metrology tools. The apparatus includes an outer structure for supporting a metrology instrument, and a chuck for holding a specimen with respect to the metrology instrument in an intended defined position for performing measurements on the specimen by the metrology instrument. The apparatus also includes at least one active vibration isolator means coupled to the chuck for compensating relative movement between the specimen and the metrology instrument. A method is also provided that includes detecting change of position of the specimen in response to mechanical vibrations, and effectuating an active modification of the position of the chuck in response to the detection for counteracting a relative displacement between the specimen and the metrology instrument.

Abstract: An apparatus for accepting and transferring at least one disk-like member is provided. The apparatus includes a pick- and place-mechanism including gripping means. In effect, the mechanism is adapted to provide pick- and/or place-cycles, which during operation provides a movement of said gripping means between an up and a down position and vice versa, whereby, in the down position, said gripping means either picks the disk-like member from a load position or places the disk-like member onto the load position.

Abstract: The invention is in particular a supporting device for relative supporting loads with respect to a base comprising a load side part, a base side part, and an intermediate part giving support to the load side part, and thus defining a supporting direction with reference to the base and the load side, including a pressure chamber bounded by chamber walls.

Abstract: Control of an active vibration isolation system with a digital controller, which includes an FPGA system (5) as the control unit. The FPGA system (5) is made up of freely programmable gate arrays with a sensor control matrix (51), which calculates axis signals in required degrees of freedom, with a control cascade block (53) for the axis signals containing several biquad filters (531, 532, 533, 534, 535), and with an output signal calculation block (55) for calculating digital actuator actuation signals. A digital signal processor (9) is connected in parallel with the FPGA system (5) in order to calculate controls with low phase loss requirements.

Abstract: An electrostatic gripper for moving wafers includes bipolar electrodes with an insulating layer of zirconium oxide, which are positioned on a circuit board. The gripper is produced by a pressing process and can be operated with a DC voltage of less than 900 V. As a result, heating of the wafer is almost completely prevented even under a vacuum.

Abstract: An apparatus for accepting and transferring at least one disk-like member is provided. The apparatus includes a pick- and place-mechanism including gripping means. In effect, the mechanism is adapted to provide pick- and/or place-cycles, which during operation provides a movement of said gripping means between an up and a down position and vice versa, whereby, in the down position, said gripping means either picks the disk-like member from a load position or places the disk-like member onto the load position.

Abstract: An imaging and raster-mode scanning apparatus has a compensation device for compensating for ambient influences that may degrade the imaging, comprising an electrical filter, and at least one sensor for providing a first signal dependent on the ambient influences the first signal passes through the filter directly and drives an internal actuator and a internal control elements of the apparatus, which has an effect on the imaging and on the image display, in a calibrated state of the apparatus, which comprises a setting of a transfer characteristic of the filter, image degradations are greatly reduced or essentially compensated for. The filter for calibrating the apparatus, has a calibration input and a second signal is applied to the calibration input of the filter.

Abstract: There is provided a method and an apparatus for isolating mechanical vibrations reacting to beam metrology tools. The apparatus includes an outer structure for supporting a metrology instrument, and a chuck for holding a specimen with respect to the metrology instrument in an intended defined position for performing measurements on the specimen by the metrology instrument,. The apparatus also includes at least one active vibration isolator means coupled to the chuck for compensating relative movement between the specimen and the metrology instrument. A method is also provided that includes detecting a change of position of the specimen in response to mechanical vibrations, and effectuating an active modification of the position of the chuck in response to the detection for counteracting a relative displacement between the specimen and the metrology instrument.

Abstract: In relation to a vibration isolation system, which comprises at least one vibration isolation device that can be assigned to an isolation element, the fact that a method of recording the system with the aid of a closed-loop and/or open-loop control device is provided, in which a closed-loop and/or open-loop control structure can be predefined and in which signals and/or variables related to the isolation system are picked up, processed and/or provided, and in which, on the basis of the definable structures and variables, at least one isolation system characteristic data set for assessing the vibration isolation system is formed, means that for the first time the indicative fundamentals for an open system for evaluation, closed-loop and open-loop control are provided.

Abstract: An active system for isolating vibrations includes: at least one first vibratio-isolating device, arranged between a load and a sstanding surface, for at least partially decoupling the static and dynamic forces acting between the load and the standing surface, the first vibration-isolating device includes a passively isolating coupling element for mechanically decoupling the static and dynamic forces including a natural frequency; at least one second vibration-isolating device, assigned to the load, for imparting control forces to the load for actively damping the substantially decoupled dynamic forces, the second fibratio-isolating device including a coupling element for dynamically coupling said second vibration-isolating device to the load and the first isolating device<the coupling element including a natural frequency; means for tuning the control forces of the second vibratio-isolating device and the natural frequencies, wherein the control forces of the second vibration-isolating device and the natu

Abstract: An electrostatic gripper for moving wafers includes bipolar electrodes with an insulating layer of zirconium oxide, which are positioned on a circuit board. The gripper is produced by a pressing process and can be operated with a DC voltage of less than 900 V. As a result, heating of the wafer is almost completely prevented even under a vacuum.

Abstract: A magnetic spring device with negative stiffness contains at least one first pole body combination composed of at least one first, at least one second and at least one third pole body, which each have opposite magnetic poles, with the pole bodies in the combination being aligned such that opposite poles are opposite one another and the first and the third pole bodies assume a defined distance from one another, in which the second pole body is arranged, with the pole bodies being arranged such that they can move relative to one another.