Abstract: A lithographic apparatus injects gas between a patterning device and a patterning device masking blade to help protect the patterning device from contamination. The gas may be injected into the space defined between the patterning device and the patterning device blade by one or more gas supply nozzles that are arranged on at least one side of the patterning device. The one or more gas supply nozzles are coupled to a frame which a patterning device support structure moves relative to. Each nozzle may be constructed and arranged to supply gas over at least the patterning region of the reflective patterning device.

Abstract: A lithographic apparatus injects gas between a patterning device and a patterning device masking blade to help protect the patterning device from contamination. The gas may be injected into the space defined between the patterning device and the patterning device blade by one or more gas supply nozzles that are arranged on at least one side of the patterning device. The one or more gas supply nozzles are coupled to a frame which a patterning device support structure moves relative to. Each nozzle may be constructed and arranged to supply gas over at least the patterning region of the reflective patterning device.

Abstract: A method and apparatus for correcting overlay errors in a lithography system. During lithographic exposure, features being exposed on the wafer need to overlay existing features on the wafer. Overlay is a critical performance parameter of lithography tools. The wafer is locally heated during exposure. Thermal expansion causes stress between the wafer and the wafer table, which will cause the wafer to slip if it exceeds the local frictional force. To increase the amount of expansion allowed before slipping occurs, the wafer chuck is uniformly expanded after the wafer has been loaded. This creates an initial stress between the wafer and the wafer table. As the wafer expands due to heating during exposure, the expansion first acts to relieve the initial stress before causing an opposite stress from thermal expansion. The wafer may be also be heated prior to attachment to the wafer chuck, creating the initial stress as the wafer cools.

Abstract: The present invention is directed to optical element damping systems. In particular, an eddy current damper is disclosed. The eddy current damper includes a rod, a series of conducting plates coupled to the rod, and layers of magnets. The alternating layers have alternating magnetic fields. When an optical element moves, the optical element will exert a force on the rod. The rod causes the conducting plates to move relative to the alternating layers of magnets to generate eddy currents within each of the conducting plates, such that the eddy currents damp the motion of an optical element. In an alternative embodiment, an eddy current damper motion amplifier is used to provide additional mechanical advantage that significantly increases the damping provided by the eddy current damper. Eddy current dampers are provided within conventional scanning lithography devices and optical maskless lithography devices to improve performance by stabilizing optical element motion.

Abstract: A method and apparatus for correcting overlay errors in a lithography system. During lithographic exposure, features being exposed on the wafer need to overlay existing features on the wafer. Overlay is a critical performance parameter of lithography tools. The wafer is locally heated during exposure. Thermal expansion causes stress between the wafer and the wafer table, which will cause the wafer to slip if it exceeds the local frictional force. To increase the amount of expansion allowed before slipping occurs, the wafer chuck is uniformly expanded after the wafer has been loaded. This creates an initial stress between the wafer and the wafer table. As the wafer expands due to heating during exposure, the expansion first acts to relieve the initial stress before causing an opposite stress from thermal expansion. The wafer may be also be heated prior to attachment to the wafer chuck, creating the initial stress as the wafer cools.

Abstract: In a gas gauge, effects due to changes in the local environment are reduced by causing a measurement nozzle and a reference nozzle to react as if they were co-located, or located at approximately the same position. This is achieved by venting the reference nozzle in very close proximity to the measurement nozzle. A reference chamber surrounding the reference plate and reference nozzle is vented at approximately the same location as the measurement nozzle. In an embodiment for use in a vacuum environment, the measurement nozzle is surrounded with an annular ring. The measurement annular ring is connected to an annular ring around the reference nozzle, which acts to co-locate the reference nozzle and the measurement nozzle. To avoid choked flow, another annular ring or rings may be placed around the measurement annular ring.

Abstract: A method and system for correcting optical aberrations in a maskless lithography system. Adjusters move individual spatial light modulators (SLMs) in an SLM array so that the surface of the SLM array deviates from a flat plane. The deviation compensates for aberrations in the lithography system, such as total focus deviation. In an embodiment, an individual SLM can be tilted, bent, and/or have its elevation changed. Multiple SLMs in the SLM array can move in different ways depending on the compensation to be made. The adjusters can be either actively or passively controlled. The method may be performed only during initial setup of the maskless lithography system, periodically as needed for maintenance of the lithography system, or prior to each exposure in the lithography system.

Abstract: An apparatus and method of transferring and loading a reticle onto a receiving station (for example, a reticle exposure stage). The reticle is first retrieved from a storage facility with an end effector having a reticle plate coupled to a mounting plate. The mounting plate connects the end effector to a robotic arm. The reticle is aligned in an out-of-plane position in an off-line alignment station. The alignment is in compliance with the alignment requirement at the receiving station. The reticle is mounted onto the reticle plate after undergoing the alignment at the off-line alignment station. The reticle is then transferred from the off-line alignment station to the receiving station while maintaining the previous alignment at the off-line alignment station. The apparatus further provides rigidity of the mounted reticle to ensure compliance with the alignment requirement at the receiving station.

Abstract: A choked-flow orifice gas gauge proximity sensor for sensing a difference between a reference surface standoff and a measurement surface standoff is disclosed. Unlike existing proximity sensors, the gas gauge proximity sensor of the present invention replaces the use of a mass flow controller with a choked flow orifice. The use of a choked flow orifice provides for reduced equipment cost and improved system reliability. A gas supply forces gas into the proximity sensor. The gas is forced through the choked flow orifice to achieve sonic conditions at which time the mass flow rate becomes largely independent of pressure variations. The flow of gas proceeds from the choked flow orifice into a sensor channel system. A mass flow sensor within the sensor channel system monitors flow rates to detect measurement standoffs that can be used to initiate a control action.

Abstract: A vacuum-driven gas gauge proximity sensor for sensing a difference between a reference surface standoff and a measurement surface standoff is disclosed. Unlike existing proximity sensors, the vacuum-driven gas gauge proximity sensor uses a vacuum to reverse the traditional flow of gas through a proximity sensor, such that gas flows inward across measurement and reference standoffs through measurement and reference nozzles. The conditioned ambient gas that is vacuumed into the reference and measurement nozzles flows through reference and measurement channels that are coupled at a junction into a single channel. The single channel is coupled to the vacuum that is used to evacuate the conditioned ambient gas through the proximity sensor. A bridge channel couples the reference and measurement channels. A mass flow sensor along the bridge channel monitors flow rates to detect measurement standoffs that can be used to initiate a control action. A pump-driven liquid flow proximity sensor is also disclosed.

Abstract: A method and apparatus for correcting overlay errors in a lithography system. During lithographic exposure, features being exposed on the wafer need to overlay existing features on the wafer. Overlay is a critical performance parameter of lithography tools. The wafer is locally heated during exposure. Thermal expansion causes stress between the wafer and the wafer table, which will cause the wafer to slip if it exceeds the local frictional force. To increase the amount of expansion allowed before slipping occurs, the wafer chuck is uniformly expanded after the wafer has been loaded. This creates an initial stress between the wafer and the wafer table. As the wafer expands due to heating during exposure, the expansion first acts to relieve the initial stress before causing an opposite stress from thermal expansion. The wafer may be also be heated prior to attachment to the wafer chuck, creating the initial stress as the wafer cools.

Abstract: A vacuum-driven gas gauge proximity sensor for sensing a difference between a reference surface standoff and a measurement surface standoff is disclosed. Unlike existing proximity sensors, the vacuum-driven gas gauge proximity sensor uses a vacuum to reverse the traditional flow of gas through a proximity sensor, such that gas flows inward across measurement and reference standoffs through measurement and reference nozzles. The conditioned ambient gas that is vacuumed into the reference and measurement nozzles flows through reference and measurement channels that are coupled at a junction into a single channel. The single channel is coupled to the vacuum that is used to evacuate the conditioned ambient gas through the proximity sensor. A bridge channel couples the reference and measurement channels. A mass flow sensor along the bridge channel monitors flow rates to detect measurement standoffs that can be used to initiate a control action. A pump-driven liquid flow proximity sensor is also disclosed.

Abstract: A choked-flow orifice gas gauge proximity sensor for sensing a difference between a reference surface standoff and a measurement surface standoff is disclosed. Unlike existing proximity sensors, the gas gauge proximity sensor of the present invention replaces the use of a mass flow controller with a choked flow orifice. The use of a choked flow orifice provides for reduced equipment cost and improved system reliability. A gas supply forces gas into the proximity sensor. The gas is forced through the choked flow orifice to achieve sonic conditions at which time the mass flow rate becomes largely independent of pressure variations. The flow of gas proceeds from the choked flow orifice into a sensor channel system. A mass flow sensor within the sensor channel system monitors flow rates to detect measurement standoffs that can be used to initiate a control action.

Abstract: The present invention is directed to optical element damping systems. In particular, an eddy current damper is disclosed. The eddy current damper includes a rod, a series of conducting plates coupled to the rod, and layers of magnets. The alternating layers have alternating magnetic fields. When an optical element moves, the optical element will exert a force on the rod. The rod causes the conducting plates to move relative to the alternating layers of magnets to generate eddy currents within each of the conducting plates, such that the eddy currents damp the motion of an optical element. In an alternative embodiment, an eddy current damper motion amplifier is used to provide additional mechanical advantage that significantly increases the damping provided by the eddy current damper. Eddy current dampers are provided within conventional scanning lithography devices and optical maskless lithography devices to improve performance by stabilizing optical element motion.

Abstract: In a gas gauge, effects due to changes in the local environment are reduced by causing a measurement nozzle and a reference nozzle to react as if they were co-located, or located at approximately the same position. This is achieved by venting the reference nozzle in very close proximity to the measurement nozzle. A reference chamber surrounding the reference plate and reference nozzle is vented at approximately the same location as the measurement nozzle. In an embodiment for use in a vacuum environment, the measurement nozzle is surrounded with an annular ring. The measurement annular ring is connected to an annular ring around the reference nozzle, which acts to co-locate the reference nozzle and the measurement nozzle. To avoid choked flow, another annular ring or rings may be placed around the measurement annular ring.

Abstract: An apparatus and method of transferring and loading a reticle onto a receiving station (for example, a reticle exposure stage). The reticle is first retrieved from a storage facility with an end effector having a reticle plate coupled to a mounting plate. The mounting plate connects the end effector to a robotic arm. The reticle is aligned in an out-of-plane position in an off-line alignment station. The alignment is in compliance with the alignment requirement at the receiving station. The reticle is mounted onto the reticle plate after undergoing the alignment at the off-line alignment station. The reticle is then transferred from the off-line alignment station to the receiving station while maintaining the previous alignment at the off-line alignment station. The apparatus further provides rigidity of the mounted reticle to ensure compliance with the alignment requirement at the receiving station.

Abstract: An apparatus, system, and method for configuring a dual isolation system lithography tool is described. An isolated base frame is supported by a non-isolated tool structure. A wafer stage component is supported by the isolated base frame. The wafer stage component provides a mount for a semiconductor wafer. A reticle stage component is supported by the isolated base frame. The reticle stage component provides a mount for a reticle. An isolated bridge provides a mount for a projection optics. The isolated bridge is supported by the isolated base frame. Alternatively, an isolated bridge is supported by a non-isolated base frame. A wafer stage component is supported by the non-isolated base frame. A reticle stage component is supported by the non-isolated base frame. An isolated optical relay is supported by the non-isolated base frame. The isolated optical relay includes one or more individually servo controlled framing blades.

Abstract: In a gas gauge, effects due to changes in the local environment are reduced by causing a measurement nozzle and a reference nozzle to react as if they were co-located, or located at approximately the same position. This is achieved by venting the reference nozzle in very close proximity to the measurement nozzle. A reference chamber surrounding the reference plate and reference nozzle is vented at approximately the same location as the measurement nozzle. In an embodiment for use in a vacuum environment, the measurement nozzle is surrounded with an annular ring. The measurement annular ring is connected to an annular ring around the reference nozzle, which acts to co-locate the reference nozzle and the measurement nozzle. To avoid choked flow, another annular ring or rings may be placed around the measurement annular ring.

Abstract: An apparatus and method of transferring and loading a reticle onto a receiving station (for example, a reticle exposure stage). The reticle is first retrieved from a storage facility with an end effector having an reticle plate coupled to a mounting plate. The mounting plate connects the end effector to a robotic arm. The reticle is aligned in an out-of-plane position in an off-line alignment station. The alignment is in compliance with the alignment requirement at the receiving station. The reticle is mounted onto the reticle plate after undergoing the alignment at the off-line alignment station. The reticle is then transferred from the off-line alignment station to the receiving station while maintaining the previous alignment at the off-line alignment station. The apparatus further provides rigidity of the mounted reticle to ensure compliance with the alignment requirement at the receiving station.

Abstract: A retractable proximity sensor system with a self-compensating mechanism to reduce the impact of mechanical instability on the precision of a proximity sensor is disclosed. The retractable proximity sensor system includes a retractable proximity sensor and a proximity sensor housing in which the housing includes a reference plate that is either integral or affixed to the housing. The proximity sensor precisely detects very small distances between a measurement probe and a work surface, such as, for example, a semiconductor wafer. A method is provided for extending and retracting a proximity sensor and compensating for the drift associated with the mechanical instability of a proximity sensor head to improve precision.