Apparatus and method for the electrochemical etching of a wafer
AssigneeInternational Business Machines Corporation
InventorsMadhav Datta, Daniel Charles Edelstein, Cyprian Emeka Uzoh
Life of this patent
Estimating the term…
Abstract
An electrochemical etching apparatus and method increasing the rate at which material is removed from a substrate such as a metallic surface. The apparatus includes an electrolyte delivery system positioned below and centered beneath the center of the substrate (e.g., a wafer) to be etched so that the center axis of the delivery system corresponds to the center of the wafer. The electrolyte delivery system and the wafer are then rotated relative to each other as the electrolyte is discharged from the delivery system and toward the surface of the wafer. A corresponding method for electrochemically etching a surface of the wafer with an electrolyte is also provided.
Claims30
An apparatus for electrochemically etching a surface of a workpiece with an electrolyte, comprising:
- an electrochemical etching circuit;
- a cell having a base;
- a cover mating with the cell to define an enclosure and having a holder adapted to receive the workpiece so that the surface of the workpiece faces toward the enclosure, the holder including an electrical contact connected to the electrochemical etching circuit and positioned to engage the surface of the workpiece;
- a head electrically connected to the electrochemical etching circuit, the head extending from the base of the cell toward the holder and the cover and having a plurality of nozzles adapted to direct the electrolyte from the head toward the surface of the workpiece received by the holder;
- and
- means for rotating the workpiece within the enclosure and means for rotating the head within the enclosure, so that both the workpiece and the head are caused to rotate relative to each other.
A method for electrochemically etching a surface of a workpiece with an electrolyte, comprising the steps of:
- placing the workpiece in an apparatus including a cell and a cover which mates with the cell to define an enclosure, wherein the cover has a holder for receiving the workpiece and wherein the holder has an electrical contact connected to an electrochemical etching circuit;
- positioning the workpiece in the holder so that the surface of the workpiece faces a head located within the enclosure, wherein the head includes a plurality of electrolyte-issuing nozzles and wherein the head is electrically connected to the electrochemical etching circuit;
- retaining the workpiece within the holder;
- electrically connecting the surface of the workpiece to the electrochemical etching circuit;
- and
- rotating the workpiece within the enclosure and rotating the head within the enclosure so that both the workpiece and the head are caused to rotate relative to each others while issuing the electrolyte from the nozzles of the head toward the surface of the workpiece retained in the holder.
Dependencies are inferred from the claim text.