System and method for enhanced control of copper trench sheet resistance uniformity
US7851234B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 29, 2007 |
| Grant date | Dec 14, 2010 |
| Priority date | — |
| Expiry date | Sep 23, 2028 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/14
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method is disclosed for controlling the sheet resistance of copper trenches formed on semiconductor wafers. The method includes forming a plurality of copper-filled trenches on a wafer, measuring the sheet resistance of each of the plurality of copper-filled trenches, and comparing the measured sheet resistance values to a predetermined sheet resistance value. Photolithography steps performed on subsequent wafers are adjusted according to a difference between the measured sheet resistance values and the predetermined value. In one embodiment, this adjustment takes the form of adjusting a photolithographic extension exposure energy to thereby adjust the cross-section of the resulting trenches.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.