Patent ID: 6383918
Filing Date: 2002-05-07
Classification: H01L

Abstract:
A method for forming an opening to a semiconductor contact in an interlayer dielectric layer and a dielectric etch stop layer on a semiconductor wafer during semiconductor manufacturing comprising the steps of:etching a portion of the interlayer dielectric layer in a predetermined configuration to form a first portion of the opening using a first high etch selective chemistry selective for the interlayer dielectric layer relative to the dielectric etch stop layer; said first high etch selective chemistry utilizing a fluorocarbon plasma having a high carbon to fluorine ratio whereby polymerization occurs forming a polymer over said first portion of the opening; removing said polymer from said first portion of the opening in the interlayer dielectric layer; etching a portion of the dielectric etch stop layer in said predetermined configuration to form a second portion of the opening open to the semiconductor contact using a second high etch selective chemistry selective for the dielectric etch stop layer relative to the semiconductor contact; and applying said second high etch selective chemistry selective to a portion of the semiconductor contact in said predetermined configuration providing a process time window for the semiconductor contact from above 70 to about 110 seconds.