Projection electron beam lithography apparatus and method employing an estimator
US7305333B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 10, 2006 |
| Grant date | Dec 4, 2007 |
| Priority date | — |
| Expiry date | Jun 1, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/3174
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A process and method for projection beam lithography which utilizes an estimator, such as a Kalman filter to control electron beam placement. The Kalman filter receives predictive information from a model and measurement information from a projection electron beam lithography tool and compensates for factors which cause beam placement error such as wafer heating and beam drift. The process and method may also utilize an adaptive Kalman filter to control electron beam placement. The adaptive Kalman filter receives predictive information from a number of models and measurement information from a projection electron beam lithography tool and compensates for factors which cause beam placement error such as heating and beam drift. The Kalman filter may be implemented such that real-time process control may be achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.