Coherent, Inc.

Applied Materials, Inc.

Etec Systems, Inc.

Other

Lumenis Inc.

David Trost

James L Hobart

Edward D Reed, Jr

Dennis G Fischer

Philip Baumeister

Bassam Shamoun

Kevin P Connors

David A Dewey

Lee H Veneklasen

Gerald M Mitchell

J Michael Yarborough

Michael Arnett

Thomas W McCurnin

Kenneth J Bossie

Robert B Estrada

Lawrence Muray

Tai-Hon Philip Chang

Dale E Koop

James Spallas

Ho-Seob Kim

Francis Chilese

Robert Innes

Sergey Babin

Jerzy Orkiszewski

Robert J Rorden

Gregory Dumond

Jeffrey Varner

This invention is directed to precision positioning devices which are well suited to manufacturing and inspection of semiconductor devices. A pair of coil assembles are attached to a base plate. The base plate forms a static portion of a gas bearing assembly. A carriage assembly, forming a movable portion of the gas bearing assembly, is capable of in-plane motion over the coil assembly. The carriage assembly contains permanent magnets and a soft magnetic bridge. A metrology component, such as a mirror, is attached to the carriage kinematically. Three in-plane constraints consist of substantially straight line connections between the metrology component and the carriage in a plane substantially parallel to the plane of motion of the gas bearings. Three out-of-plane constraints on the metrology component comprise substantially straight line connections between it and the gas bearings. The positioning device is operable in vacuum by directing the flow of gas out of the bearings to a vacuum pump. The positioning device is further capable of creating an area of low stray magnetic fields through the use of moving magnetic shielding material.

Positioning device

The present invention relates generally to methods, apparatus and materials to reduce or minimize the heating of a substrate (and associated distortions of the photomask) caused by electron-beam energy deposited in the substrate during patterning. Heating of the substrate is exacerbated by radiative transfer of infrared energy from the substrate to other nearby components of the e-beam apparatus followed by reflection or re-radiation of a portion of the energy back to the substrate. The present invention provides useful materials and methods for reducing such reflection or re-radiation effects, leading to temperature stability of the substrate, reduced thermal distortion and the possibility of increased patterning accuracy. The infrared absorbing materials of the present invention also possess sufficient electrical conductivity to dissipate scattered electrons residing on the material, and sufficient thermal conductivity to dissipate heat rapidly and not result in local heating or significant temperature rise of the absorber. The semiconducting material silicon carbide (SiC) is satisfactory for the practice of the present invention. Doped SiC having altered electrical conductivity may also be used. It is shown that emission and re-absorption from the uncoated face of the substrate dominates the substrate's temperature rise.

Method of reducing heat-induced distortion of photomasks during lithography

Disclosed is a positioning stage for precisely positioning an object within a limited range of travel (e.g. 100 &mgr;m). By way of example, the stage can be used to position an electron source such as a field emitter in an electron beam microcolumn. The stage includes a block which defines a channel to allow flexure along a first axis. The block also defines another channel to allow flexure along a second axis perpendicular to the first axis. Using actuators in the channels to flex a portion of the block, the object supported by the block can be precisely positioned to a desired location in a horizontal plane defined by the first and second axes.

High precision flexure stage

The present invention relates generally to methods, apparatuses and materials to reduce or minimize the heating of a substrate (and associated distortions of the photomask) caused by electron-beam energy deposited in the substrate during patterning. The present invention provides useful materials and methods for reducing such reflection or re-radiation effects, leading to temperature stability of the substrate, reduced thermal distortion and the possibility of increased patterning accuracy. The infrared absorbing materials of the present invention also possess sufficient electrical conductivity to dissipate scattered electrons residing on the material, and sufficient thermal conductivity to dissipate heat rapidly and not result in local heating or significant temperature rise of the absorber.

System to reduce heat-induced distortion of photomasks during lithography

An electron beam writing system includes an electron beam patterning machine operable to emit an electron beam to form a pattern on a substrate. A computer control system, coupled to the electron beam patterning machine, has a plurality of pre-computed distortion maps. Each distortion map describes expected distortions of the substrate caused by bulk heating resulting from exposure to the electron beam. The computer control system controls the electron beam patterning machine using the distortion maps in order to adjust for the expected distortions.

System and method to correct for distortion caused by bulk heating in a substrate

A surgical laser scanner having optics that scans a pulsed laser beam onto a target tissue is disclosed. The laser scanner has a lens and a scanning mirror or mirrors located upstream of the lens at a distance substantially equal to the focal length of the lens. The laser beam hits the scanning mirror and is reflected onto the lens in a pattern defined by sequential positions of the scanning mirror. The laser beam is projected onto the target tissue by the lens in a direction parallel to the optical axis of the lens. The projected pattern has a constant size regardless of the distance between the laser scanner and the target tissue.

Hand-held laser scanner

Typically, a laser emits significant energy after a control signal is generated to disable the power supply. The inherent delay between generation of a control signal for shutting off a laser power supply and actual termination of an output beam pulse in response to the control signal, is compensated in the context that the control signal is generated automatically upon coincidence of measured output beam power with a preset threshold value. Power supplied to a laser is modulated to cause generation of a pulsed laser output beam. The cumulative energy of each output beam pulse is monitored and a feedback signal indicative of measured output beam pulse energy is supplied to the power supply. The feedback signal is compared with a user-selected threshold value, and a control signal is generated for terminating the output beam pulse (by terminating input power to the laser) when the measured output pulse energy reaches the threshold value. By generating the threshold signal to have a value representing a threshold output beam pulse energy that is lower than a desired output beam pulse energy, the threshold signal is generated in a manner which compensates for the inherent delay between generation of the control signal and the actual termination of the output beam pulse in response to the control signal. This prevents delivery of significant output beam energy in excess of a user-selected amount.

Electronically pulsed laser system

A pulsed solid state laser system is disclosed which utilizes a plurality of individual laser rods which are sequentially pumped and whose beans are combined into a single interleaved output bean. The individual laser rods are pumped at an average power level which is below that for maximum output power from each rod, thereby obviating the need for refrigeration cooling. A compact optical system is disclosed which permits a constant beam size even at different pump levels and other advantages. A compact cooling system is also disclosed.

Apparatus for combining laser beams

An electron beam pattern generating system for exposing a pattern on a substrate using a raster scan method. The system stores a rasterized representation of the pattern as a plurality of regular pixel dose exposure levels. These pixel dose exposure levels are evaluated by the system for one or more proximity effects and corrections to the dose exposure level and/or pixel location are calculated. The system includes apparatus for both calculation and storage of intermediate and final results as required. As they are calculated, the corrections are provided to an exposure dose modulator wherein they are applied to forming the pattern. Thus corrections for both long range and short range proximity effects due to both electron scattering and heating as well as for proximity effects due to global thermal expansion can be calculated and provided during run-time and a corrected pattern exposed.

Method and apparatus for run-time correction of proximity effects in

A vacuum compatible linear motion device having a fluid bearing is contained within a vacuum chamber having a working pressure of significantly less than one atmosphere. The fluid bearing is contained within a vacuum enclosure within the vacuum chamber and is maintained at a pressure higher than that of the vacuum chamber but less than one atmosphere, thus essentially isolating the fluid bearing. A moveable payload is coupled to the linear motion device such that linear motion in the direction of the long axis of the device is provided to the moveable payload.

Vacuum compatible linear motion device

A liquid circulation system for cooling a laser head is disclosed. The circulation system comprises a main storage tank for holding a cooling liquid and a pump for circulating the liquid from the tank through the laser head and back into the tank. The cooling system includes a heat exchanger for cooling the liquid. The heat exchanger includes liquid carrying coils and an impeller fan rotatable about an axis. The fan being located adjacent the coils for drawing air across the coils in an axial direction with respect to the fan and for expelling the air radially with respect to the fan.

Liquid circulation system for cooling a laser head

Solid state laser with relay optics

A device is disclosed for delivering laser radiation to a target. The device includes an elongated, hollow, tubular member having an input end and a delivery end. A window is mounted near the delivery end of the device. The window provides a seal preventing smoke and debris from contaminating the interior of the device. In the preferred embodiment, the window is formed from a crystalline material, such as diamond, which has low absorption level for laser light and excellent thermal characteristics. In addition, the thickness of the window is selected to reduce reflection losses and increase the transmission level through the window without the need for fragile antireflection coatings.

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San Francisco, CA, United States of America

David Trost