Method and system for detecting and correcting problematic advanced process control parameters
US10295993B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 2012 |
| Grant date | May 21, 2019 |
| Priority date | — |
| Expiry date | Aug 2, 2034 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02P90/02
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
The invention may be embodied in a system and method for monitoring and controlling feedback control in a manufacturing process, such as an integrated circuit fabrication process. The process control parameters may include translation, rotation, magnification, dose and focus applied by a photolithographic scanner or stepper operating on silicon wafers. Overlay errors are used to compute measured parameters used in the feedback control process. Statistical parameters are computed, normalized and graphed on a common set of axes for at-a-glance comparison of measured parameters and process control parameters to facilitate the detection of problematic parameters. Parameter trends and context relaxation scenarios are also compared graphically. Feedback control parameters, such as EWMA lambdas, may be determined and used as feedback parameters for refining the APC model that computes adjustments to the process control parameters based on the measured parameters.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.