Patent ID: 7378341

Claim:
A method for controlling after-etch-inspection critical dimension (AEI CD) of a contact hole, comprising: depositing a dielectric layer over a substrate; performing a chemical mechanical polishing (CMP) process to planarize the dielectric layer, wherein a remaining dielectric layer has a first thickness; depositing a cap oxide layer having a second thickness, wherein a combination of the first thickness and the second thickness is substantially constant; altering and pre-determining an after-develop-inspection critical dimension (ADI CD) of a contact hole to be formed on the substrate based on the second thickness of the cap oxide layer; forming a photoresist layer on the cap oxide layer; performing a lithographic process to form an opening in the photoresist layer, wherein the opening has the pre-determined after-develop-inspection critical dimension (ADI CD); and performing a dry etching process and using the photoresist layer as an etching hard mask to etch the cap oxide layer and the dielectric layer through the opening to form a contact hole therein, wherein the contact hole has an after-etch-inspection critical dimension (AEI CD).