AUTOMATIC PROCESS CONTROL OF AFTER-ETCH-INSPECTION CRITICAL DIMENSION

摘要

Automatic process control of after-etch-inspection critical dimension. A dielectric layer is deposited over a substrate and is then planarized to a first thickness. A cap oxide layer having a second thickness is deposited, wherein the combination of the first thickness and the second thickness is substantially constant. An ADI CD of a contact hole to be formed on the substrate is altered and pre-determined based on the second thickness of the cap oxide layer. A photoresist layer is formed on the cap oxide layer. An opening having the predetermined ADI CD is formed in the photoresist layer. Using the photoresist layer as an etching mask, the cap oxide layer and the dielectric layer is etched through the opening to form a contact hole having an AEI CD.