Patent ID: 8274161
Filing Date: 2012-09-25
Classification: B23K,H01L

Abstract:
1. A serial thermal processing arrangement for treating a pre-assembled chip/substrate assembly of spaced-apart, pre-soldered semiconductor components in a linear chip processor, through a series of independent, linearly adjacent chambers, wherein: a pre-assembled chip/substrate is loaded onto a support plate in a chamber at an initial Load/Lock station of the processor, the pre-assembled chip/substrate being held at atmospheric pressure, and the chamber is purged with nitrogen gas; the pre-assembled chip/substrate is advanced into a first treatment chamber or station, and the pre-assembled chip/substrate assembly is heated to a pre-set temperature of from about 150° C. to about 270° C. for a particular solder utilized, wherein the first chamber is held below atmospheric pressure, and a formic acid vapor vent is introduced to the chamber; the pre-assembled chip/substrate assembly is advanced to a second chamber or station, the pre-assembled chip/substrate assembly is heated to a pre-set temperature of from about 150° C. to about 270° C. for the particular solder utilized, while holding the second chamber at a vacuum, and a formic acid vapor vent is introduced into the second chamber; the pre-assembled chip/substrate assembly is advanced from the second station to a third chamber or station, the pre-assembled chip/substrate assembly is heated to a pre-set temperature of from about 150° C. to about 270° C. for the particular solder utilized therewith and is held to a vacuum, and a formic acid vapor vent is introduced to the chamber; the pre-assembled chip/substrate assembly is advanced from the third station to a fourth station, and the pre-assembled chip/wafer assembly is heated at a pre-set temperature of from about 150° C. to about 270° C. for the particular solder utilized between the spaced-apart chip and substrate to electrically join the solder of the chip and the substrate, a formic acid vapor vent being introduced to the chamber; the pre-assembled chip/substrate assembly is advanced from the fourth station to a fifth station, and the pre-assembled chip/wafer assembly is heated at a pre-set peak temperature of from about 150° C. to about 270° C. for the particular solder utilized between the spaced-apart chip and substrate to fully electrically and mechanically join the solder of the chip and the substrate, a formic acid vapor vent being introduced to the chamber; the joined chip/substrate assembly is advanced from the fifth station to a sixth station for cooling the now joined and electrically conductive components of the assembly at ambient or room temperature of about 20° C. to about 30° C.; and the chip/substrate assembly is shuttled to a final downstream Load/Lock station for unloading the joined chip/substrate assembly from the chamber at the Load/Lock station.