Highly purified metal material and sputtering target using the same
US5679983A · kind A · utility
10Cited by
14References
3Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 31, 1995 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | May 31, 2015 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
This is a highly purified metal comprising one metal selected from the group consisted of titanium, zirconium and hafnium. The highly purified metal has an Al content of not more than 10 ppm. It also has an oxygen content of more than 250 ppm, each of Fe, Ni and Cr contents not more than 10 ppm and each of Na and K contents not more than 0.1 ppm. The highly purified metal is obtained by either purifying crude metal by the iodide process or surface treating crude metal to remove a contaminated layer existing on the surface thereof and then melting The surface treated material with electron bean in a high vacuum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.