Method for integrated circuit fabrication using pitch multiplication
US7547640B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2006 |
| Grant date | Jun 16, 2009 |
| Priority date | — |
| Expiry date | Oct 30, 2026 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/95
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Different sized features in the array and in the periphery of an integrated circuit are patterned on a substrate in a single step. In particular, a mixed pattern, combining two separately formed patterns, is formed on a single mask layer and then transferred to the underlying substrate. The first of the separately formed patterns is formed by pitch multiplication and the second of the separately formed patterns is formed by conventional photolithography. The first of the separately formed patterns includes lines that are below the resolution of the photolithographic process used to form the second of the separately formed patterns. These lines are made by forming a pattern on photoresist and then etching that pattern into an amorphous carbon layer. Sidewall pacers having widths less than the widths of the un-etched parts of the amorphous carbon are formed on the sidewalls of the amorphous carbon. The amorphous carbon is then removed, leaving behind the sidewall spacers as a mask pattern. Thus, the spacers form a mask having feature sizes less than the resolution of the photolithography process used to form the pattern on the photoresist. A protective material is deposited around th…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.