Method of improved copper gap fill
US6399486B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 22, 1999 |
| Grant date | Jun 4, 2002 |
| Priority date | — |
| Expiry date | Nov 22, 2019 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/76883
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention teaches a special annealing process to “heal” electrochemical copper deposited (ECD) defects in a dual damascene via and trench structure. The annealing step is processed after the electrochemical deposition (ECD) of the top excess copper and before the chemical mechanical polishing (CMP) of the copper. The key processing steps of this invention are the special annealing steps at key temperatures, ambient, pressures and times to anneal out the defective copper voids in the dual damascene structure. These annealing conditions are special annealing steps to promote low temperature copper surface diffusion to “heal” the voids and other defectives within the copper trench and via structure. The special annealing conditions of: temperature, ambient, pressure and time are the following: temperature in a range of about 300 to 500° C., ambient of nitrogen N2, hydrogen H2 gases (reducing atmosphere to remove copper oxide, N2/H2 plasma preferred), pressure in a range of about 100 MPa to 600 MPa, time in a range of about 0.5 to 10 minutes. These conditions are designed to take advantage of low temperature surface diffusion mechanisms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.