Method and apparatus for reducing incidental exposure by using a phase shifter with a variable regulator
US6573010B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 25, 2001 |
| Grant date | Jun 3, 2003 |
| Priority date | — |
| Expiry date | Nov 14, 2021 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F1/70
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
One embodiment of the invention provides a system for reducing incidental exposure caused by phase shifting during fabrication of a semiconductor chip. The system operates by identifying a problem area of likely incidental exposure in close proximity to an existing phase shifter on a phase shifting mask, wherein the problem area includes a polysilicon line passing through a field region of the semiconductor chip. The system places an additional phase shifter into the problem area on the phase shifting mask so that a regulator within the additional phase shifter protects the polysilicon line passing through the field region. This additional phase shifter has a wider regulator than the existing phase shifter, wherein the existing phase shifter is used to expose a polysilicon line in a gate region of the semiconductor chip.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.