Single-Crystal Silicon Embedded With Insulated Conducting Wires
Original Publication Date: 1989-Aug-01
Included in the Prior Art Database: 2005-Jan-28
In packaging technology, a generic problem is that the packaging materials tend to have a different thermal expansion coefficient from that of silicon. Consequently, upon thermal cycling during operation a shear stress is exerted on those solder balls that join the chip and module, and fatigue failure of the balls occurs. This problem limits the size of the chip since the magnitude of the shear depends on the chip size. In order to overcome this problem so that a large chip can be used in VLSI, there has been a long term effort to develop ceramics which have the same thermal expansion coefficient as that of silicon. However, the material which has the best match of expansion coefficient with silicon is silicon itself.