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 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 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: One or more patterning arrays are mounted to a mounting plate via height adjustment structures that enable the flatness of the active surfaces of the patterning arrays to be controlled. The height adjustment structures may comprise an array of piezoelectric actuators or screws. Alternatively, the backside of the patterning means may be polished to optical flatness and bonded by crystal bonding to an optically flat surface of a rigid mounting body.

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: Apparatus is disclosed for automatically transferring a semiconductor wafer between a horizontal and a vertical plane, beginning and ending in precisely located positions. A wafer support arm is carried by a transfer member which also includes a motor for rotating the support arm between a "start" position and an intermediate position in a horizontal plane. Another motor is provided for rotating the transfer member to position the support arm in a vertical plane. The wafer support arm is then returned to its original position relative to the transfer member, thus establishing a "finish" position in the vertical plane.

Abstract: A wafer cassette transfer mechanism is disclosed which transfers a wafer cassette from a transfer arm to an elevator. The elevator moves vertically, up or down, so as to move the wafer cassette to a second transfer arm. The second transfer arm can then move the wafer cassette to after processing equipment.