High-strength and high-conductivity Cu-(Ni, Co, Fe)-Si copper alloy for use in leadframes and method of making the same
US6506269B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 21, 2001 |
| Grant date | Jan 14, 2003 |
| Priority date | — |
| Expiry date | Sep 21, 2021 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC22C9/06
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A high-strength and high-conductivity copper alloy is disclosed which contains essentially of: (a) from 0.5 to 2.5 wt % of Ni; (b) from 0.5 to 2.5 wt % of Co; (c) from 0.5 to 0.8 wt % of Si; (d) from 0.05 to 0.15 wt % of either Mg or P or both; and (e) the balance of Cu. The amounts of Co, Ni, and Si satisfy the following equations: 2%≦(Ni+Co)≦4%, and 0.8≦(Ni/4+Co/6)/Si≦1.2. The new copper alloy exhibits substantially improved electrical conductivity, greater than 65% IACA, than the commercially available C7025 copper alloy, while maintaining a satisfactory tensile strength (greater than 600 MPa), and, thus, can be most advantageously used for preparing leadframes for use in high pin-number (greater than 100 pins) IC application.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.