Critical dimension shrink through selective metal growth on metal hardmask sidewalls
US9716038B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2016 |
| Grant date | Jul 25, 2017 |
| Priority date | — |
| Expiry date | Mar 31, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02E10/47
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method for fabricating a self-aligned via structure includes forming a tri-layer mask on an ILD layer over a lower metal wiring layer, the tri-layer mask includes first and second insulating layers and a metal layer in between the insulating layers; defining a trench pattern through the first insulating layer and metal layer, the trench pattern having a first width; defining a first via pattern in a lithographic mask over the trench pattern, the first via pattern having a second width that is larger than the first width; growing a metal capping layer on an exposed sidewall of the trench pattern to decrease the first width to a third width that defines a second via pattern; transferring the trench pattern into the ILD layer to form a trench; and transferring the second via pattern through the ILD layer and into the metal wiring layer to form a via.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.