Electron beam lithography proximity correction method
US4520269A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 3, 1982 |
| Grant date | May 28, 1985 |
| Priority date | — |
| Expiry date | Nov 3, 2002 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31769
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
Proximity effect is reduced or eliminated by breaking each shape of a lithographic exposure pattern into two parts, a perimeter part having a width on the order of the lithographic exposure pattern minimum linewidth and the remaining central part or parts (if any) which are completely surrounded by the perimeter part. The lithographic exposure pattern is then modified by moving or setting back the edges of each central part away from the perimeter part which surrounds it (similar to reducing the size of the central part) to form a nominally unexposed band separating each central part from the perimeter part which surrounds it. The width of the nominally unexposed band in the modified exposure pattern is preferably chosen as large as possible so long as the condition is met that upon developing a radiation sensitive layer directly exposed to the modified exposure pattern, the nominally unexposed band develops (i.e., dissolves, resists dissolution, or is otherwise modified) substantially as if it were also exposed. The nominally unexposed band is exposed, in fact, by electrons scattered from the directly exposed part(s) of the shape (the perimeter part plus the central part, if any).…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.