| 摘要 |
PCT No. PCT/CA96/00863 Sec. 371 Date Jul. 7, 1998 Sec. 102(e) Date Jul. 7, 1998 PCT Filed Dec. 19, 1996 PCT Pub. No. WO97/23121 PCT Pub. Date Jun. 26, 1997A connective medium is provided for use in ball grid assemblies for detachable connections between electronic devices and circuit boards. The medium includes novel, discrete spheres defining an inner metallic, spherical core and one or more outer, electrically conductive concentric, hard and non-deformable metallic layers of nickel, copper or alloys thereof and a coating of silver or gold thereon. |
