Reticle having a number of subfields
US5523580A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 23, 1993 |
| Grant date | Jun 4, 1996 |
| Priority date | — |
| Expiry date | Dec 23, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31794
- WIPO fieldMicro-structural and nano-technology
- WIPO sectorChemistry
Abstract
A reticle for an electron beam system for direct writing applications has a base layer that contains a reticle pattern; a set of reinforcing struts connected to the base layer separating the base layer into a set of non-contiguous subfields; in which the pattern is carried by a set of apertures areas in said base layer; and in which the set of non-contiguous subfields has overlapping rim portions in which the overlap portions of corresponding lines have a pattern that produces the correct exposure when the subfields are correctly aligned and minimizes pattern feature discontinuities when the subfields are misaligned. A corresponding method consists of overlapping the reticle at the field or subfield boundaries and forming a spatial breakup or a partially transmissive area of the pattern elements contained in the overlapped areas, preventing shorts and open failures in the lines or pattern elements and providing additional tolerance for the alignment of the adjacent fields or subfields.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.