FUNDAMENTALS OF PROCESS CONTROL
This is the introduction to a series of 10 installments which will discuss fundamental truths about process control—inspection and metrology—for the semiconductor industry.
By fundamental, we imply the following:
- Unassailable: They are self-evident, can be proven from first principles, or are supported by the dominant behavior at fabs worldwide
- Unchanging: These concepts are equally true today for 28nm as they were 15 years ago for 0.25μm, and are expected to hold true in the future
- Universal: They are not unique to a specific segment of process control; rather they apply to process control as a group, as well as to each individual component of process control within the fab
Each article in this series will introduce one of the 10 fundamental truths and discuss interesting applications of these truths to semiconductor IC fabs. Given the increasing complexity of advanced devices and process integration, process control is growing in importance. By understanding the fundamental nature of process control, fabs can better implement strategies to identify critical defects, find excursions, and reduce sources of variation.
ARTICLES
- Truth I: You Can’t Fix What You Can’t Find. You Can’t Control What You Can’t Measure
- Truth II: It Is Always More Cost-Effective To Over-Inspect Than Under-Inspect
- Truth III: The Most Expensive Defect Is The One That Wasn’t Detected Inline
- Truth IV: Always Quantify Your Lots At Risk When Making Changes To Your Process Control Strategy
- Truth V: Variability Is The Enemy Of A Well Controlled Process
- Truth VI: Time Is The Enemy Of Profitability
- Truth VII: Improving Yield Also Improves Device Reliability
- Truth VIII: Process Control Requirements Increase With Each Design Rule
- Truth IX: High-Stakes Problems Require A Layered Process Control Strategy
- Truth X: Adding Process Control Reduces Production Costs And Cycle Time
