Process for Elongating Semiconductor Device Solder Connections
Original Publication Date: 1984-Aug-01
Included in the Prior Art Database: 2005-Feb-04
In joining semiconductor devices to conductive lands on a ceramic substrate by the reflow of solder balls or pads, which provide both the electrical connection to the conductive lands and the mechanical support for the chip, thermal stresses in the solder connections can be generated during thermal cycling. The thermal stresses can present reliability problems over long periods of time, particularly when the coefficient of expansion of the device and the supporting substrate differ by a significant amount. It has been suggested that the stresses in the connections can be reduced by elongating the connections. In this process for stretching solder connections, a spring clip 10 of the proper weight is attached to the device 12 after the initial solder connections 14 have been established.