Abstract: An apparatus and a method for baking and cooling silicon substrates are disclosed. Both baking and cooling of silicon substrates are done in a single integrated thermal process module. Each thermal process module includes two hot plate assemblies, a cool plate assembly, two local linear transfer arms and a micro-processor based module controller. Both transfer arms are capable of transferring substrates among the cool and hot plate assemblies. The module controller ensures that there are no conflicts in use of the transfer arms or in use of the hot and cool plate assemblies and so that a transfer arm is always available when a substrate is finished baking. A central substrate handling robot transports substrates only from and to the cool plate assembly of the thermal process module. Also, the vacuum tubing is routed via a unique pulley arrangement to achieve compact mounting and eliminate loose tubing.

Abstract: An apparatus and method are provided for efficiently and effectively coating a substantially flat surface, i.e., a substrate, with a high-viscosity chemical such as photoresist. The chemical is dispensed through a piezo electrically controlled droplet jet cartridge on to the surface. The thickness of the chemical coating is controlled by controlling the rate at which chemical is dispensed through the droplet jet cartridge. A number of droplet jet cartridges are aligned such that gaps in chemical dispensed by one droplet jet cartridge are filled by chemical dispensed by other droplet jet cartridges. An array of droplet jet cartridges which spans the width of the surface moves across the surface to coat the surface with chemical in a single pass. To coat a circular surface, the surface is spun while a droplet jet cartridge is moved from the center of the surface to the outer edge of the surface. Chemical is dispensed on to the surface in a helical pattern.

Abstract: An apparatus and method are provided for efficiently and effectively coating a substantially flat surface, i.e., a substrate, with a high-viscosity liquid chemical, such as photoresist. The flat surface is oscillated by rotating the surface in one direction and then repeatedly reversing the direction of rotation of the surface. The chemical is spread by both the centrifugal force of the rotation of the surface and the tangential force of the angular acceleration of the surface. The tangential force helps spread the chemical without prematurely overcoming the surface tension of the chemical resulting in a particularly effective coating using substantially less chemical. Chemical is alternatively spread by vibrating the flat surface. Vibrating applies to the chemical, in addition to radial, centrifugal force, if any, non-radial forces which are not directly opposed by surface tension. The chemical is therefore spread more evenly and efficiently without overcoming the surface tension of the chemical.

Abstract: A substrate photolithography system includes a substrate handling robot that pivots about a fixed point and transfers substrates between photoresist coater, a developer, and a heating/cooling unit, all of which are clustered about the robot. The end effector of the robot is capable of both vertical and lateral movement so that individual modules of the heating/cooling unit may be stacked. For heating/cooling, the substrate is placed in the heating/cooling unit in close proximity to a hotplate/chillplate and a thermally conductive, non-reactive gas, such as helium, is introduced into the airspace between the substrate and the hotplate/chillplate. The thermally conductive, non-reactive gas, is preheated/precooled before introduction into the airspace between the substrate and the hotplate/chillplate when the gas passes through a bore in the hotplate/chillplate. Additionally, the substrate is automatically aligned in a milled recession in the hotplate surface for future handling.

Abstract: A substrate photolithography system includes a substrate handling robot which pivots about a fixed point and transfers substrates between photoresist coater, a developer, and a heating/cooling unit, all of which are clustered about the robot. The end effector of the robot is capable of both vertical and lateral movement so that individual modules of the heating/cooling unit may be stacked. An apparatus and a method for baking and cooling silicon substrates are disclosed. Both baking and cooling of silicon substrates are done in a single integrated thermal process module. Each thermal process module includes two hot plate assemblies, a cool plate assembly, two local linear transfer arms and a micro-processor based module controller. Both transfer arms are capable of transferring substrates among the cool and hot plate assemblies. A cassette input/output unit handles cassettes which contain semiconductor wafers or other substrates that are to be delivered to or withdrawn from a semiconductor processing system.

Abstract: In a photolithography system, baking and cooling of semiconductor substrates is done in a thermal process module that uses a unique mechanism including pulleys to route vacuum tubing to a transfer arm. Specifically, the mechanism includes a pair of pulleys and a vacuum tube wrapped around the pulleys. The vacuum tube has a movable portion connected to the transfer arm which is reciprocable between the pair of pulleys. The vacuum tube also has a stationary portion that is connected to the movable portion to form an endless loop. The stationary portion of the vacuum tube is rigidly connected to a vacuum supply line in the housing of the thermal process module.

Abstract: An apparatus and method are provided for controlling the rate of drying of a high-viscosity chemical applied to a substantially flat surface of a spinning article. The rate of drying of the chemical is controlled by controlling the saturation level of a solvent in the local atmosphere in which the article is spinning, i.e., in the air space adjacent to the surface of the article. By spinning the article in a solvent-laden vapor, the evaporation of solvent from the chemical is slowed and therefore the rate at which the chemical dries and thickens is also slowed. Spreading of the chemical may also be facilitated and premature drying of the chemical may be avoided by applying to the surface of the article a thin layer of the solvent prior to application of the chemical.

Abstract: A cassette input/output unit handles cassettes which contain semiconductor wafers or other substrates that are to be delivered to or withdrawn from a semiconductor processing system. The input/output unit includes a drawer front which rotates 90.degree. about a horizontal axis as it is opened. Thus a cassette containing wafers can easily be placed on the drawer front with the wafers oriented vertically, as they are normally carried, and the cassette will be rotated 90.degree. as the drawer is closed, thereby orienting the wafers horizontally for access by a robot inside the photolithography system. The cassette may also be rotated about a vertical axis within the unit, so that several input/output units may be used with a robot which rotates about a fixed axis. A clamping mechanism grips the cassette firmly when it is placed in the unit.

Abstract: An apparatus and method for dispensing liquid at a controlled temperature in a spin coating or developer machine are disclosed. The apparatus is a thermal control line that has an inner core wall that encloses at least one conduit for a liquid dispense line and an outer annular wall that encloses at least one chamber for circulation of coolant. The inner core wall and the outer annular wall are formed of such materials as to permit efficient heat exchange between the coolant and the liquid. The coolant is circulated in the annular chamber at a rate sufficient to maintain the dispensed liquid at a desired temperature.

Abstract: An improved nozzle assembly for dispensing liquid is disclosed. In a first embodiment of the invention, the liquid dispenser comprises a nozzle assembly with an expansive cavity at its dispensing end. When the flow of liquid in the dispenser is halted, a pocket of liquid formed inside the cavity ties the liquid in the nozzle to the liquid in a drop formed at the tip of the nozzle. Thus, when "suck-back" is applied, the drop is pulled into the cavity and up the nozzle, leaving at most a very small and stable amount of liquid inside the cavity. In a second embodiment of the invention, an inner nozzle tube extends beyond the end of an outer nozzle tube, creating an external annular recess which captures and holds a drop of liquid over the end of the nozzle. After suck-back, the drop is pulled up into the nozzle, leaving a small, stable amount of liquid in the annular recess.

Abstract: A photoresist drainage system for conducting the excess photoresist and solvents from a spin coating machine in a semiconductor fabrication unit is disclosed. The excess photoresist liquid and solvents are channeled directly to an exhaust manifold instead of being collected in a temporary storage tank. From the exhaust manifold the photoresist and solvents flow directly into a factory chemical reclaim system. This substantially reduces the amount of solvent vapors that are drawn into the factory exhaust system.