Method and apparatus for selective removal of material from wafer alignment marks

Abstract

A process and apparatus for locally removing any material, such as a refractory metal, in particular tungsten, from any desired area of a wafer, such as an alignment mark area of a silicon wafer in process during the formation of integrated circuits thereon. The process comprising the steps of aligning said area of said wafer, such as an alignment mark on the wafer, to an etchant dispensing apparatus, placing the surface of the wafer adjacent at least a portion of an annular portion of the etchant dispensing apparatus, dispensing at least one etchant onto said area of said wafer, such as an alignment mark, and removing the at least one etching from the wafer. The apparatus for the cleaning of an area of a semiconductor wafer using a material comprising a tube having a bore therethrough and exterior wall, the tube supplying material to said area of the wafer and an annular member having an interior wall surrounding the tube, the annular member having a thin edge thereon for positioning adjacent a portion of the area of the wafer during the cleaning thereof, the annular member forming an annular space between the exterior wall of the tube and the interior wall of the annular member.