Abstract: A method for the selective removal of the metal film layer accumulated upon a photoresist layer during processing of substrates using a stream of carbon dioxide spray without disturbing conductor portions is provided. A constant stream of high pressure CO2 snow is applied to the metal film layer thereby rapidly cooling the metal layer on top of said resist layer causing it to shrink rapidly, and to debond, and peel from the photoresist layer underneath. The temperature of the substrate is raised and maintained at significantly higher than room temperature. Continuing the application of the CO2 spray causes thermal shock to the photoresist under the metalized layer causing large cracks in the remaining metal layer portions, said cracks typically including at least one loose metal edge. The CO2 spray is continually applied to the cracks thereby peeling away the remaining metal portions, leaving the exposed photoresist and underlying surface features.

Abstract: Liquid CO2 is expanded in specially designed primary and secondary nozzles to produce frozen solid CO2. The impurities initially contained in the liquid CO2 are trapped inside of the frozen CO2, which is collected in a clean container. The container is emptied on top of a high purity surface. The impurities are concentrated on the surface, since these impurities are non-volatile and do not escape with the CO2 gas formed as the frozen CO2 is heated by the ambient temperature to its sublimation point. After all of the frozen CO2 has sublimed, the surface can be analysed by standard analysis methods to determine quantity and composition of the impurities. The determination and quantification of non-volatile impurities, such as organic oils and greases, in the CO2 supply that feeds, for example, cleaning systems utilizing CO2, is thus made possible.

Abstract: Liquid CO2 is expanded in specially designed primary and secondary nozzles to produce frozen solid CO2. The impurities initially contained in the liquid CO2 are trapped inside of the frozen CO2, which is collected in a clean container. The container is emptied on top of a high purity surface. The impurities are concentrated on the surface, since these impurities are non-volatile and do not escape with the CO2 gas formed as the frozen CO2 is heated by the ambient temperature to its sublimation point. After all of the frozen CO2 has sublimed, the surface can be analysed by standard analysis methods to determine quantity and composition of the impurities. The determination and quantification of non-volatile impurities, such as organic oils and greases, in the CO2 supply that feeds, for example, cleaning systems utilizing CO2, is thus made possible.

Abstract: A CO2 jet spray nozzle comprising multiple nozzle orifices for use in producing CO2 jet spray. The nozzle comprises a body, an elongated nozzle tube extending from the body having an axial hole therein, and an orifice disk disposed at the base of the nozzle tube in the axial hole. The orifice disk contains a plurality of orifices disposed therein that form a critical orifice and that is an integral part of the nozzle. The orifices may be drilled by means of a laser beam or electron discharge machining through the orifice disk. The orifice disk and nozzle tube are typically welded together to prevent leakage. By fabricating different nozzles in which the orifice size, orifice geometry (round, oval, or elongated slit), total orifice area, nozzle diameter and nozzle length is varied within a well defined matrix, any intensity of CO2 jet spray may be obtained. By varying the arrangement of the orifices, nozzle geometry, and nozzle length, different spray patterns may be provided.

Abstract: An apparatus and method that enhances removal of contaminating particles from surfaces of a non-electrostatically sensitive components that are cleaned using a carbon dioxide cleaning spray. The apparatus includes a programmable power supply that is connected to ground and to the non-electrostatically sensitive component. The surface charge of the component is determined by cleaning the surface without adding any voltage or charge bias to the component. Then the surface is reversed-biased with a voltage having the opposite polarity by a large amount using the programmable power supply. The surface is then cleaned a second time, which removes the contaminating particles that were bound to the surface by electrostatic forces generated during the first cleaning. Thus, reversing the polarity of the charge on the surface that is to be cleaned removes the strong attraction between the contaminating particles and the surface and enhances removal of the contaminating particles from the surface.

Abstract: Apparatus for cleaning a moving pallet and components carried thereby. The apparatus includes a processing system that employs the moving pallet. An environmental cleaning station is provided through which the pallet moves. The cleaning station includes a recirculating blower system and a high efficiency particulate air filter. A ducting system or warm air system may be provided for supplying purified air, inert gas, or warm air to eliminate condensation. A carbon dioxide jet spray cleaning system is provided that has jet spray nozzles disposed within the cleaning station that are coupled by way of a manifold to a liquid carbon dioxide tank that supplies liquid carbon dioxide to the jet spray nozzles. The jet spray nozzles generate a carbon dioxide snow spray that impinges on the moving pallet to clean it along with the components it carries.

Abstract: Apparatus and methods for removing particles from a surface of a semiconductor wafer or optical component using a carbon dioxide snow spray directed at the wafer or component while simultaneously irradiating the surface with a laser beam. The apparatus comprises a carbon dioxide jet spray cleaning system disposed within an environmental cleaning station of a processing system that processes the wafer or component. The processing system is a conveyorized system wherein a conveyor belt or web transports wafers or components from processing station to processing station. The cleaning station includes a recirculating blower system, a laminar flow screen, a high efficiency particulate air filter, and a ducting system for recirculating purified air or inert gas. The cleaning station contains a jet spray nozzle that produces a carbon dioxide snow spray. The jet spray nozzle is coupled by way of a manifold to a liquid carbon dioxide tank that supplies liquid carbon dioxide to the jet spray nozzle.

Abstract: Apparatus for cleaning, assembling, testing and inspecting contamination sensitive hardware. The apparatus includes an environmental process enclosure having an inner processing chamber, and a carbon dioxide jet spray cleaning system. The enclosure includes a loadlock pass-through having front and rear access doors for providing access to the inner processing chamber. A blower is disposed in the enclosure for circulating purified gas therethrough. A prefilter disposed prior to an inlet of the blower, and a high purity filter and laminar flow screen are disposed in the inner processing chamber. A heater is provided for heating the purified gas and a temperature controller is coupled to the heater for controlling the temperature of the purified gas. A table is disposed in the inner processing chamber upon which contamination sensitive hardware and testing and assembly apparatus may be placed.

Abstract: A method of removing photoresist or redeposited material from a substrate or other surface using a carbon dioxide jet spray. A substrate having photoresist or redeposited material on its surface is disposed in an environmental enclosure. A carbon dioxide jet spray is generated and directed onto the surface of the substrate and photoresist or redeposited material. The carbon dioxide jet spray cools or freezes the material and causes a mismatch in the thermal coefficient of expansion of the material and the substrate. The material debonds from the substrate due to the induced thermal shock to the material. This rapid shrinkage loosens the material and allows the solid particles in the spray to knock the material from the surface of the substrate. The removed photoresist or redeposited material may be collected in a filter, and removed.

Abstract: An apparatus and method that enhances removal of contaminating particles from surfaces of a static-sensitive components that are cleaned using a carbon dioxide cleaning spray produced by a jet spray gun. The apparatus has a programmable power supply that is connected to ground, to the static-sensitive component, and to the jet spray gun. The static-sensitive component is cleaned using the cleaning spray and the surface charge generated on the surface of the component or substrate is simultaneously monitored to determine the amount and polarity of the charge that is generated thereon. The programmable power supply then applies a reverse bias to the jet spray gun that is equal to and has the opposite polarity of the charge that is generated on the surface of the static-sensitive component or substrate, which neutralizes the charge generated on the surface of the component.

Abstract: In accordance with the teachings of the present invention, an apparatus and method for cleaning large glass plates each having first and second major surfaces is provided. The apparatus (10) includes an enclosure (14) which maintains a cleaning environment in which a glass plate (42) is decontaminated. An actuated support member (40) vertically translates the glass plate (42) into the enclosure (14) where it is supported with its first (46) and second (48) major surfaces substantially perpendicular to a ground plane defined by the floor space (12) occupied by the apparatus (10). A pair of opposing arrays of jet spray nozzles (62 and 64) coupled to a pressurized supply of liquid carbon dioxide (94) is provided for simultaneously directing carbon dioxide snow particles (96) in directions of the first and second major surfaces (46 and 48) of the glass plate (42), thereby removing contamination therefrom. The carbon dioxide snow particles (96) sublime within the cleaning environment of the enclosure (14).

Abstract: Apparatus for cleaning disks during processing. The apparatus is used with a disk processing system having a conveyor belt for transporting a disk carrier containing disks. The conveyor belt and the disk carrier have openings therein. A cleaning station is disposed above the conveyor belt and has an opening therein that isolates the cleaning station from the processing system. The cleaning station has a recirculating blower system, a laminar flow screen, a HEPA filter, and a ducting system for recirculating purified air or inert gas. A carbon dioxide jet spray cleaning system is provided that has a plurality of sets of jet spray nozzles disposed in the cleaning station that are coupled by way of manifolds to a liquid carbon dioxide tank that supplies liquid carbon dioxide to the nozzles.

Abstract: Detection apparatus for use with a carbon dioxide jet spray cleaning system that determines whether liquid carbon dioxide is flowing between a storage tank and a jet spray nozzle. The detection apparatus determines whether carbon dioxide snow is generated by the jet spray nozzle, which is produced by expansion of liquid carbon dioxide through the jet spray nozzle. The apparatus comprises a transfer tube coupled between the storage tank and the jet spray nozzle that has transparent input and output windows and which permits liquid carbon dioxide to flow from the storage tank to the jet spray nozzle. A light source produces light that is focused on a pinhole in an aperture stop. A collimating lens images collimated light on the input window of the transfer tube, and a light detector detects light that is refracted by liquid carbon dioxide in the transfer tube that exits through the output window and is incident thereon, and generates an output signal indicating light detection.

Abstract: Apparatus for cleaning a wafer carrying cassette. The cassette is fabricated as open top box having closed sides and a plurality of grooves formed in its interior that each hold a wafer. The apparatus includes an enclosure having an entry and an exit, and a conveyor is provided for transporting the cassette through the enclosure. A first plurality of jet spray nozzles are disposed adjacent to the entry that produce a carbon dioxide jet spray that cleans exterior surfaces of the cassette as it travels through the entry. A blower produces a flow of air through the enclosure and a filter filters the air flowing through the enclosure. A second plurality of moveable jet spray nozzles is controlled to move into the interior of the cassette to generate a carbon dioxide spray that cleans the interior of the cassette. An electrostatic control system is provided that controls buildup of electrostatic charge on the cassette caused by the carbon dioxide spray.

Abstract: A method of cleaning an integrated circuit chip module prior to attaching wire bonds thereto. The method involves disposing a module containing an integrated circuit chip and IC bond pads without wire bonds in an environmental process enclosure. A carbon dioxide jet spray cleaning system having a spray nozzle and orifice assembly is disposed the environmental process enclosure. A jet spray of carbon dioxide is generated using the jet spray cleaning system. The carbon dioxide jet spray is directed onto the surface of the module such that the spray impacts the IC bond pads and module bond pads to clean unwanted adhesive from the surface of the module and thus clean the IC and module bond pads.