Lithography method for doubled pitch
US9156306B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 25, 2011 |
| Grant date | Oct 13, 2015 |
| Priority date | — |
| Expiry date | Jul 18, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76897
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Lithography method for etching very dense patterns on a substrate, based on a combination of several less dense partial patterns; a sacrificial layer is formed on a substrate and is etched according to a first partial pattern; spacers are formed on edges of elements of the sacrificial layer, the spacers defining a second partial pattern; then the sacrificial layer is removed leaving only the spacers remaining. A layer sensitive to an electron beam is subsequently deposited between the spacers to a thickness less than or equal to the height of the spacers, and this sensitive layer is exposed using an electron beam according to a third partial pattern such that there remains on the substrate a final pattern of regions lacking spacers and a sensitive layer, this pattern resulting from the combination of the second and third partial patterns and having higher density than each of the partial patterns.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.