Highly purified metal material and sputtering target using the same
US5196916A · kind A · utility
38Cited by
11References
36Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 15, 1991 |
| Grant date | Mar 23, 1993 |
| Priority date | — |
| Expiry date | Feb 15, 2011 |
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 not 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 beam in a high vacuum.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.