Martensitic Materials for Solderless Interconnection
Original Publication Date: 1988-Jul-01
Included in the Prior Art Database: 2005-Feb-15
Materials which transform martensitically when stressed mechanically are used for conducting interconnectors which solderlessly bond to a metal line at one end of a through-hole in an insulating material by impact hammering. Mechanical stress generated by impact hammering causes expansion of the connector in the through-hole anchoring the connector therein. Examples of useful martensitic materials are iron- nickel alloys with about 28% to 32% nickel and copper aluminum nickel alloys with about 28% aluminum and 0% to 4% nickel. The figure shows an example of the use of this concept in microelectronics for solderless joining of I/O pins to a substrate on which a semiconductor chip is electrically mounted. The pins permit electrical connection of the substrate to a printed circuit board.