摘要:
This invention is directed to electro-magnetic alignment devices, which are particularly adapted, among other possible uses, for use in aligning the wafers in a microlithography system, said devices comprising in combination a base plate, a first current carrying coil assembly mounted on the base plate, a second current carrying coil assembly mounted on the base plate in spaced relationship with respect to the first coil assembly, a first magnet mounted adjacent the first coil assembly and a second magnet mounted adjacent the second coil assembly, an upper connecting piece connecting the first and second magnets, a mount for receiving an object on the upper connecting piece, the base plate and magnets and upper connecting piece coacting to form a magnetic circuit, a controller for controlling the flow and direction of current through the coil assemblies to move the magnets and upper connecting piece with respect to the base plate, a plurality of linear actuators mounted between the magnets and the upper connecting piece respectively for moving the connecting piece with respect to the magnets.
摘要:
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.
摘要:
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.
摘要:
A waveguide including a folded, coated reflector highly reflective of radiation having two different wavelengths over a wide range of incidence angles, including grazing incidence angles. The waveguide can be employed for guiding laser radiation useful for medical or other applications, such as a combined HeNe and CO.sub.2 laser beam. In some embodiments, the invention is a hollow waveguide formed by folding a flat, coated substrate into a polygonal shape. Because the coated substrate is folded, rather than rolled into a cylindrical tube, the bending stress on the coating is concentrated at the corners of the polygonal waveguide rather than distributed over the waveguide's entire surface. Although the coating may crack at the corners of the waveguide's polygonal cross-section, the flat surfaces between the waveguide edges will be intact, and the cracks in the corners will have an insignificant effect on waveguide performance.
摘要:
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.
摘要:
A dichroic optical filter including a substrate that is substantially transparent to visible radiation, and an oxide semiconductor layer on the substrate for reflecting an infrared wavelength (such as an infrared treatment beam wavelength). An example of a suitable oxide semiconductor for reflecting a treatment beam from a CO.sub.2 layer is indium tin oxide. Preferably, the filter includes a specially designed multilayer coating on the oxide semiconductor layer to enhance the reflection of infrared and longer wavelength radiation. This multilayer coating includes alternating quarter-wave layers of high and low refractive index materials, each having an optical thickness substantially equal to a quarter-wavelength of infrared radiation to be reflected. Preferably also, the multilayer coating includes a thin multilayer coating between each pair of adjacent quarter-wave layers, with these thin multilayer coatings being designed to enhance the filter's transmission of visible radiation, while not significantly affecting the filter's reflection of infrared wavelengths. Also preferably, the multilayer coating includes a second multilayer coating which reflects a narrow band of visible radiation (such as visible radiation from a HeNe laser aiming beam), while transmitting most visible wavelengths.
摘要:
A coated reflector reflective of radiation having two different wavelengths over a wide range of incidence angles, including grazing incidence angles. The coated reflector can be employed in a waveguide for laser radiation useful for medical or other applications, such as a combined HeNe and CO.sub.2 laser beam. Preferably, the coated reflector includes a metal substrate and a multi-layer stack thereon, the multi-layer stack consists of alternating dielectric layers of high and low refractive index material, each pair of adjacent high and low index layers of the stack has a combined matched optical thickness substantially equal to an incident short (e.g., visible) wavelength multiplied by a factor M/2, and the total matched optical thickness of the stack is substantially equal to (2N-1).lambda..sub.L /8, where M and N are positive integers and .lambda..sub.L is an incident long wavelength (such as the wavelength of a CO.sub.2 laser beam). Preferably, the substrate is silver, the high index dielectric is zinc sulfide, and the low index dielectric is yttrium fluoride or cerium fluoride. In other embodiments, the invention is a coated substrate having substantially parallel indentations along which it can be folded into a polygonal shape for use a waveguide.
摘要:
An improved apparatus for manually manipulating a surgical laser beam is disclosed. The preferred embodiment of the invention includes a mirror nominally positioned at a 45 degree angle to the incident laser beam, a joy stick for manipulating the mirror, and a linkage interconnecting the two. The mirror is mounted to allow it to rotate about two mutually perpendicular and intersecting axes. The linkage operates to direct the reflected laser beam in two orthogonal dimensions such that a ratio between the movement of the reflected beam in each dimension is equivalent to the ratio of the movement of the joy stick in each dimension. This yields a reflected laser beam that moves a distance proportional to the amount of motion input to the joy stick. The reduction or amplification ratio between the input motion and the reflected laser beam motion remains constant, regardless of the direction of motion. In this manner, by moving the joy stick in a circular motion, the reflected laser beam also moves in a circular motion, rather than in an elliptical motion. A simplified joint that allows spherical rotation and axial translation between its two members is also disclosed. In the preferred embodiment, an adjustable hand rest is provided that moves out of the way when not in use.
摘要:
This invention is directed to electromagnetic alignment apparatus, which is particularly adapted, among many other possible uses, for use in aligning the wafers in a microlithography system, said apparatus comprising in combination three or more spaced magnets, three or more coil assemblies mounted to pass through the magnetic fields of the magnets respectively, means for controlling the flow of current through the coil assemblies respectively, said coil assemblies being joined together to form a structure movable with respect to the magnets and adapted to carry an object thereon, the coil assemblies being wound with respect to each other so that by controlling the supply of current to the coils the structure can be moved selectively in three degrees of freedom.
摘要:
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.