Abstract: A removable cover for protecting a reticle used in a lithography system is described. The removable cover includes a frame and a membrane supported by the frame. The membrane is transparent to an inspection wavelength such that the reticle can be inspected with the removable cover in place. This removable cover protects the reticle when the removable cover is in place and is removable for lithographic exposure. The removable cover can further include at least one reticle fastener that applies force to the reticle thereby preventing movement of the removable cover relative to the reticle when the removable cover is in place. A plurality of fasteners are used to position and secure the removable cover and reticle. A method of performing lithography and a lithographic system are also described.

Abstract: An improved method and apparatus for coating semiconductor substrates with organic photoresist polymers by extruding a ribbon of photoresist in a spiral pattern which covers the entire top surface of the wafer. The invention provides a more uniform photoresist layer and is much more efficient than are current methods in the use of expensive photoresist solutions. A wafer is mounted on a chuck, aligned horizontally and oriented upward. An extrusion head is positioned adjacent to the outer edge of the wafer and above the top surface of the wafer with an extrusion slot aligned radially with respect to the wafer. The wafer is rotated and the extrusion head moved radially toward the center of the wafer while photoresist is extruded out the extrusion slot. The rotation rate of the wafer and the radial speed of the extrusion head are controlled so that the tangential velocity of the extrusion head with respect to the rotating wafer is a constant.

Abstract: A spin coating process for controlling the mean thickness of photoresist on the surface of a semiconductor wafer. The wafer surface has a central axis normal to the surface. The process comprises the steps of applying the solution to the wafer surface and spinning the wafer about the central axis at a spindle speed until the solution has dried. The spindle speed is a function of the desired mean thickness of the photoresist, the barometric pressure and the relative humidity. The spindle speed is determined from a statistical model described by the equation: MT=A+B×RH+C×BP+D/SS1/2 wherein: MT is mean thickness in Å; RH is relative humidity in percent; BP is barometric pressure in mm of Hg; SS is spindle speed in rpm; and A, B, C and D are constant coefficients.

Abstract: The present invention relates to chemical delivery systems and methods for delivery of liquid chemicals. In one embodiment, the present invention relates to systems having multi-reservoir load cell assemblies for delivering chemicals used in the semiconductor industry. In one embodiment, the present invention provides a multi-reservoir load cell assembly, including a controller, a buffer reservoir, a main reservoir, one or more load cells, coupled to the assembly and to the controller, operable to weigh the liquid in the reservoir(s), a plurality of supply lines, each supply line having a valve and connecting one of the supply containers to the main reservoir, and a gas and vacuum sources for withdrawing the liquid from the assembly when demanded by the controller and for refilling the assembly from the supply containers.

Abstract: The invention provides a hot plate oven suitable to bake materials on substrates such as flat panel displays and large semiconductor wafers such as 300 mm in diameter and above. The hot plate oven in one embodiment includes an insulated chamber, a heater in the chamber, a door for entry of a substrate, a frame, preferably water cooled, for suspending the substrate above the heater, a substrate lowering mechanism to hold the frame and lower the substrate to a certain height above the heater at least one fluid cooled pin to counteract sag when the substrate is heated, and a set of manifolds and valves to feed and exhaust gases, vapors, and apply a vacuum to the chamber. In another feature, the oven assembly includes a stack of low profile ovens, each having a door on the side for entry of a substrate.

Abstract: In summary, the vertical rapid cooling furnace of this invention for treating semiconductor wafers with self contained gas chilling and recycling comprises a hot wall reaction tube positioned within a cylindrical array of heating coils. Space between the hot wall reaction tube and said array of heating coils provides a cooling gas passageway therebetween. The cooling gas passageway has an inlet and an outlet, a chilled gas inlet communicating with the inlet of the cooling gas passageway and a heated gas outlet communicating with the outlet of the cooling gas passageway. The furnace includes a heat exchanger having a hot gas inlet and a chilled gas outlet, the hot gas inlet thereof communicating with said heated gas outlet, and the chilled gas outlet communicating with said cooling gas passageway inlet. With this system, heated gas from the cooling gas passageway can be chilled to remove heat therefrom and returned to the cooling gas passageway to remove heat from the furnace.

Abstract: A vertical rapid heating furnace for treating semiconductor wafers comprising a hot wall reaction tube positioned within a cylindrical array of circular parallel heating elements substantially concentric therewith, each heating element being spaced from the hot wall reaction tube, each heating element comprising a coil of resistance heating conductor. The coiled resistance heating conductor can be a coil of resistance heating wire, the coil having an outer diameter of from 1 to 7 mm and supported in an annular heating element support. Each heating element support is dimensioned to support and accommodate the thermally expanded heating element supported therein at both the minimum and maximum furnace temperatures. Preferably, each annular heating element support is provided by an annular recess in the insulation surrounding the array of heating elements.

Abstract: A method of and an apparatus for coating a substrate with a polymer solution to produce a film of uniform thickness, includes mounting the substrate inside an enclosed housing and passing a control gas, which may be a solvent vapor-bearing gas into the housing through an inlet. The polymer solution is deposited onto the surface of the substrate in the housing and the substrate is then spun. The control gas and any solvent vapour and particulate contaminants suspended in the control gas are exhausted from the housing through an outlet and the solvent vapor concentration is controlled by controlling the temperature of the housing and the solvent from which the solvent vapor-bearing gas is produced. Instead the concentration can be controlled by mixing gases having different solvent concentrations. The humidity of the gas may also be controlled.

Abstract: The present invention provides a cleaning system. In one embodiment, the system includes a rotating member, a rinse member held to the rotating member, including a channel extending from an inner location to an outer edge of the rinse member for delivery of cleaning fluid through the channel during rotation of the rinse member. The system also includes a cover, disposed on the rinse member, including an opening for cleaning fluid, and a member for dispensing cleaning fluid to the rinse member. In another embodiment, the cleaning system includes an integral rinse member held to the rotating member.

Abstract: A multi-stage telescoping tube structure and a robot including a multi-stage telescoping tube structure. The multi-stage telescoping tube structure includes an outer tube, an intermediate tube, and an inner tube. The intermediate tube is slidably received in the outer tube, and the inner tube is slidably received in the intermediate tube. It further includes a multi-stage screw for arrangement translating rotary motion into linear movement of the tubes, and a drive means coupled to the screw arrangement. The robot further includes a support bracket, rotatably supporting the multi-stage telescoping tube structure, and an electric motor for rotating the arrangement. The structure further includes rail guides engagable with complimentary horizontally extending rails for horizontal movement of the robot.

Abstract: A modular system and a method of creating a modular system comprising a substantially rigid frame and a plurality of modules mounted at predetermined locations on the frame by means of kinematic couplings. The frame includes a main beam in the form of a spine, and a plurality of transversely extending bulkheads. The method includes creating a model of the system using rigid bodies and thereafter providing the frame and modules and securing them kinematically. The kinematic couplings comprise three pairs of aligning elements, each in the form of a male element and a contact element. The contact elements may take the form of grooves, tetrahedral depressions, or flat surfaces.

Abstract: A wafer gripper assembly comprises first and second gripping members movably supported relative to each other. A motor propels the gripping members linearly towards and away from each other. Preferably both gripping members are movably supported, and a rotary-to-linear translator produces equal and opposite linear movement of the gripping members. Typically, at least six contactor elements are defined on the pair of gripping members. The contactor elements include a vertically extending portion having an inwardly facing convex surface for contacting an edge of a wafer, and an inwardly extending flange for supporting a lower surface of the wafer.

Abstract: A thermal treatment boat having a plurality of annular, coaxial, spaced apart bands having substantially the same inner diameters. The bands are separated by a band spacing distance of from about 3.8 to 12.7 mm, each of the bands having a height, Height.sub.Band, in mm according to the equation: ##EQU1## wherein Height.sub.Band is always.gtoreq.wafer thickness; ColumnHeight is the total height of the treatment boat, mm; BandSpacing is the band spacing distance between adjacent bands, mm; and NumberBands is the total number of bands in the treatment boat. Preferably the NumberBands is from about 12 to about 100. Each band includes wafer support means for supporting a wafer therein at a position which is substantially centered between the upper edge surface and said lower edge surface thereof, the wafer support means in one embodiment including at least three inwardly extending projections.

Abstract: A method of and an apparatus for coating a substrate with a polymer solution to produce a film of uniform thickness, includes mounting the substrate inside an enclosed housing and passing a control gas, which may be a solvent vapor-bearing gas into the housing through an inlet. The polymer solution is deposited onto the surface of the substrate in the housing and the substrate is then spun. The control gas and any solvent vapour and particulate contaminants suspended in the control gas are exhausted from the housing through an outlet and the solvent vapor concentration is controlled by controlling the temperature of the housing and the solvent from which the solvent vapor-bearing gas is produced. Instead the concentration can be controlled by mixing gases having different solvent concentrations. The humidity of the gas may also be controlled.

Abstract: Process for treating multiple parallel wafers positioned in a heating zone surrounded by a heater emitting radiant heat. A space of from 0.5 to 2.55 cm is maintained between each wafer, and the outer portions of each wafer are shielded from radiant heat emitted by the heater by means of a circular heat shield positioned between the outer edge of the wafer and the heater. The circular heat shield has an upper edge and a bottom edge, and is positioned at a distance of less than 0.5 cm from the outer edge of the wafer. The wafer is positioned to be substantially centered between said upper edge and said bottom edge of its respective heat shield, and the circular heat shield has a height of from 0.35 to 0.95. The heat provided by the heater can be sufficient to raise the temperature of the wafers from 21.degree. C. up to 1100.degree. C. at a rate of 100.degree. C./min without causing thermal stress damage to the wafers.

Abstract: Thermal treatment boat comprising a cylinder having a central axis and a plurality of band slots having opposed upper and lower surfaces in planes perpendicular to said central axis and spaced at predetermined locations along said central axis. At least one slot in each set extends around at least 180.degree. and less than of the full circumference of said cylinder. Pairs of adjacent band slots define an annular band therebetween. The height of each slot being from about 3.8 to 12.7 mm. Each of the bands having a height, Height.sub.Band, in mm, according to the equation: ##EQU1## wherein Height.sub.Band is always .ltoreq. wafer thickness; ColumnHeight is the total height of the cylinder, mm; BandSlotHeight is the height of the slot, mm; and NumberBands is the total number of bands in the treatment boat. The cylinder can include a wafer loading effector slot therethrough in a plane of the central axis extending along the length of the cylinder.

Abstract: A chemical vapor deposition apparatus comprising a hot wall reaction tube, one or more reaction gas preheaters, a reaction gas exhaust outlet, and substantially eddy free reaction gas flow control means for passing reaction gases in a substantially laminar flow from a preheater to the exhaust outlet. The gas flow control means includes a tube flange positioned to be in a substantially eddy free relationship with the end of the wafer boat zone, the flange having a curved surface means extending from the end of the wafer boat zone to the outer tube for directing the reaction gas flow out of or into the reaction zone while maintaining the gas in a state of substantially laminar flow. One reaction gas preheater comprises a first heating tube having a removable baffle. A second reaction gas preheater comprises a two wall cylindrical heater with inner surface deformations.

Abstract: A wafer transfer mechanism used for transferring wafers between cassettes and a boat uses sensors to detect and to measure any offset of the actual center of each wafer being transferred with respect to the expected or precalibrated center of that wafer. An appropriate adjustment is made to effectively eliminate such offset so that each wafer can be transferred throughout the system without any edge contact between a wafer and the boat or the cassette. The system also includes a boat exchange unit having a rotatable turntable which is used in association with two boats. The boat exchange unit permits a continuous mode operation in which one boat can be undergoing a loading or unloading of wafers at one station on the turntable while another boat is at or is moving to or from a heating chamber loading or unloading station on the turntable.

Abstract: A wafer processing spin station includes a movable jaw chuck which is adjustable in position at the clamping position to accommodate offset of the center of the wafer with respect to the axis of rotation. A balancing apparatus and method are used with the movable jaw chuck to maintain the gripping force exerted on the wafer by the movable jaw chuck substantially unaffected by the centrifugal forces developed by the movable jaw chuck at all speeds of rotation produced during the spinning operation and within the range of the clamping positions of the movable jaw chuck.

Abstract: A wafer handling method and apparatus insures proper centering of a wafer at a work station and controls the heat transferred to the wafer in a baking operation. The amount of heat transferred and the rate at which the heat is transferred to the wafer are regulated by controlling the distance between the wafer and a hot plate. The hot plate is maintained at a constant temperature higher than the bake out or equilibrium temperature to which the wafer is to be heated.