Aluminum metallization by a barrier metal process
US6197686A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 1993 |
| Grant date | Mar 6, 2001 |
| Priority date | — |
| Expiry date | Jun 28, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A metallization method for filling an Al-based material in a contact hole having a barrier metal structure, in which high barrier characteristics and high step coverage may be achieved simultaneously, is proposed. The present invention is based on two concepts. The first concept is to provide a Ti/TiON/Ti three-layer barrier metal structure and to deposit a layer of the Al-based material by high temperature sputtering. Sufficient barrier characteristics may be provided by the intermediate TiON layer of the three-layer structure. The interface between the Al-based layer and the barrier metal layer is the Ti layer having excellent wetting characteristics with respect to the Al-based layer so that the contact hole can be filled uniformly without forming voids. The second concept is to set the substrate heating temperature during high temperature sputtering to 450 to 550.degree. C. and to set the deposition rate to 0.6 .mu.m/minute or less. In this manner, moderate Al migration and sufficiently long reaction time may be assured even on a Ti layer which partially reflects the rough surface morphology of the TiON layer for further improving reliability in filling.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.