Post-lithography misalignment correction with shadow effect for multiple patterning
US7700444B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 26, 2006 |
| Grant date | Apr 20, 2010 |
| Priority date | — |
| Expiry date | Jul 23, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76816
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Misalignment created during a multiple-patterning process is a serious challenge for critical dimension (CD) control and layout design in continuing integrated-circuit device scaling. A number of post-lithography misalignment correction technologies based on the shadow effect are invented for multi-patterning lithographic applications. When applied to transfer patterns from a top layer to an underneath layer, the subtractive shadow effect in anisotropic plasma etching combined with a hard-mask process, will shift the position of features such that the previously produced misalignment can be corrected. Also, additive shadow effect in a sputtering/evaporation process can be used. Misalignment correction methods allow the semiconductor industry to print sub-32 nm (half-pitch) features using the double-patterning technique with currently existing lithographic tools (e.g., 193-nm DUV scanner), therefore postponing the need of expensive next-generation lithography (NGL). The misalignment correction methods can be applied to existing lithography technologies to print features smaller than their physical resolution limits.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.