C4 CHIP ATTACHMENT by LOCALIZED HEATING
Original Publication Date: 1988-Apr-01
Included in the Prior Art Database: 2005-Feb-15
Semiconductor chips can be attached to polyimide film chip carriers using C4 technology. Solder is typically reflowed by heating in a furnace. A chip can thus be attached to a chip carrier by placing the entire structure to be heated on a conveyor belt which travels through a furnace. However, a more advantageous method of chip attachment is achieved by localized heating of the solder connections. The method and apparatus required for chip attachment by localized heating is herein described with reference to cross-sectional view Fig. 1 and plan view Fig. 2. (Image Omitted) The localized heating method begins with placement of chip 10 in holder plate 11 with the C4 solder balls on chip 10 face up. Holder plate 11 is maintained in place by top plate 12.