document: Integrated optical metrology controls post etch CDs Control of the transistor gate critical dimension -LRB- CD -RRB- on the order of a few nanometers is a top priority in many advanced IC fabs . Each nanometer deviation from the target gate length translates directly into the operational speed of these devices . However , using in-line process control by linking the lithography and etch tools can improve CD performance beyond what each individual tool can achieve . The integration of optical CD metrology tools to etch mainframes can result in excellent etcher stability and better control of post-etch CDs
doc_bio_tags: B I I O O O O O O O B I I I O O O O O O O O O O O O O O O O O B I O O O O O O B I I O O O O B I O O O O O O O O O O O O O O O O O O O B I O O O O O O O O O O O B I I I O B I O O O O B I O O O O O O
extractive_keyphrases: integrated optical metrology transistor gate critical dimension ic fabs target gate length operational speed optical cd metrology tools etch mainframes etcher stability cd performance
abstractive_keyphrases: post etch cd control in-line process control lithography tools photolithography