Texas Instruments Corporation

Robert F Kunesh

Richard L Guldi

Christo Pavel Bojkov

Diane Louise Arbuthnot

A method for preparing a bonding pad on an integrated circuit wafer by the steps of depositing a conductive seed layer () on the bonding pad; depositing a metal layer (, and) over a portion of the conductive seed layer; and immersing the wafer in an etchant solution () to remove the portion of the seed layer not covered by the metal layer. The etchant solution contains a chelating agent that bonds ions from the seed layer. When the seed layer is copper or a refractory metal, and the metal layer is gold or palladium, the preferred chelating agent is selected from, but is not limited to, but is not limited to, the families of ethylenediaminetetraacetic acids (EDTA), 8-hydroxy-quinolines, including 8-hydroxy-quinoline-5-sulfonic acid, porphyrins, and phthalocyanines.

Method for chemical etch control of noble metals in the presence of less noble metals

A method for a wafer cleaner using a rotation mechanism. Wafers are placed into a carrier 3 having grooves to maintain a spacing between the wafers. The carrier 3 and wafers are placed into a tank 1 with a cleaning solution. Nozzles 11 are used to direct pressurized solution against the wafers causing them to rotate within the carrier. In another embodiment, the tank 1 includes a megasonic transducer 16. In the second embodiment, the wafers are rotated while the megasonic transducer 16 is producing megasonic energy. The rotation of the wafers causes the cleaning solution and the megasonic energy to act on the wafers uniformly, and further exposes the edges of the wafers directly to the cleaning solution and the megasonic energy, thereby enhancing particle removal from the wafers. Other embodiments are provided.

Method for rotational wafer cleaning in solution

A method for cleaning a wafer carrier. A tank having sides and a bottom is provided. A weir is provided within the tank and having sides lower than the sides of the tank. Nozzles for outputting pressurized solution are provided within the weir. Laminar flow jets are also provided within the weir and are coupled to a pump for providing the laminar flow. To clean a wafer carrier, the carrier is placed within the weir. Solution is directed into the grooves of the wafer carrier using the nozzles. After the wafer carrier is cleaned using the nozzles, the nozzles are turned off. The laminar flow jets are activated using the laminar flow pump to provide a vertical laminar flow. This flow carries particles released from the wafer carrier by the pressurized solution upwards and over the weir. After a predetermined time period the cleaned wafer carrier is removed from the weir. Megasonic energy may be applied during the cleaning process to further enhance the removal of particles from the wafer carrier.

Method for wafer carrier cleaning

A method and apparatus for a wafer cleaner using a rotation mechanism. Wafers are placed into a carrier 3 having grooves to maintain a spacing between the wafers. The carrier 3 and wafers are placed into a tank 1 with a cleaning solution. Nozzles 11 are used to direct pressurized solution against the wafers causing them to rotate within the carrier. In another embodiment, the tank 1 includes a megasonic transducer 16. In the second embodiment, the wafers are rotated while the megasonic transducer 16 is producing megasonic energy. The rotation of the wafers causes the cleaning solution and the megasonic energy to act on the wafers uniformly, and further exposes the edges of the wafers directly to the cleaning solution and the megasonic energy, thereby enhancing particle removal from the wafers. Other embodiments are provided.

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Plano, TX, United States of America

Robert F Kunesh