High-purity copper sputtering targets and thin films
US6451135B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 20, 1998 |
| Grant date | Sep 17, 2002 |
| Priority date | — |
| Expiry date | Jun 6, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/2855
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
There is provided copper targets for sputtering capable of forming a deposition film with low electric resistance indispensable for high-speed operation elements and also with excellent thickness uniformity, and such thin copper films. A high-purity copper sputtering target is characterized by comprising up to 0.1 ppm each Na and K, up to 1 ppm each Fe, Ni, Cr, Al, Ca, Mg, up to 5 ppm each carbon and oxygen, up to 1 ppb each U and Th, and, excluding gaseous constituents, more than 99.999% copper. Preferably the average grain size on the sputter surface is 250 &mgr;m or below, with its dispersion thin plus or minus 20%. I(111)/I(200) of X-ray diffraction peak intensity on the sputter plane is at least 2.4 with its dispersion within plus or minus 20%.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.