High speed interconnect system with refractory non-dogbone contacts and an active electromigration suppression mechanism
US4847674A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 10, 1987 |
| Grant date | Jul 11, 1989 |
| Priority date | — |
| Expiry date | Mar 10, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/12576
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An interconnect (16', 18', 18"), whose interlevel contacts comprise refractory (10) to refractory or refractory to semiconductor substrate (13) interfaces, comprises patterned refractory core portions (10), consisting of tungsten or molybdenum, having top portions (10a) and opposed side portions (10b), provided with sidewall spacers (32a) of aluminum, gold or copper or alloys thereof and formed on surface (12a) of insulating layers (12). The sidewall spacers afford lateral low resistivity cladding of the refractory portions as well as suppression of the electromigration failure modes of voiding and whiskering, while leaving the top portion of the core portions available for refractory to refractory contacts and the bottom portion of the core portions available for refractory to refractory or refractory to silicon contacts. In this manner, an interconnect system is provided which has low electrical resistivity but which avoids the much poorer electromigration performance associated with aluminum to aluminum, aluminum to silicon, or aluminum to refractory contact-making as well as with industry-standard bilayer structures comprising refractory/aluminum for interconnect-making.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.