Charged particle beam projection method
US7939246B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jun 14, 2006 |
| Grant date | May 10, 2011 |
| Priority date | — |
| Expiry date | Mar 4, 2029 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB82Y40/00
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A deposition energy distribution when a charged particle beam is made incident upon a resist film, is approximated by a sum of element distributions having Gaussian distributions. A pattern area density map partitioning the pattern layout plane into small regions, is defined for each element distribution. First and second sub-steps are repeated for each of the pattern area density maps. In the first sub-step, an area density of each small region is obtained. In the second sub-step, in accordance with an energy deposition rate, an exposure dose assigned to a pattern in a first small region, an area of the pattern and the area density of the first small region, the deposition energy to be given to the target small region is obtained and the corrected area density is calculated. A deposition energy at an evaluation point on a pattern layout plane is calculated from the corrected area densities.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.