Flux-free chip to substrate joint serial linear thermal processor arrangement

A flux-free, 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, comprising the steps of:

• loading the pre-assembled chip/substrate 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;
• advancing the pre-assembled chip/substrate into a first treatment chamber or station, and heating the pre-assembled chip/substrate assembly to below solder melt temperature, then holding the first chamber below atmospheric pressure, and then introducing formic acid vapor vent;
• advancing the pre-assembled chip/substrate assembly to a second chamber or station, heating the pre-assembled chip/substrate assembly to a temperature above the melting temperature of the solder, then holding the second chamber at a vacuum, and then introducing a formic acid vapor vent;
• advancing the pre-assembled chip/substrate assembly from the second station to a third chamber or station, heating the pre-assembled chip/substrate assembly to a temperature above the melting point of the solder, then holding a vacuum, and then introducing a formic acid vapor vent to the chamber;
• advancing the pre-assembled chip/substrate assembly from the third station to a fourth station, and heating the pre-assembled chip/wafer assembly at an elevated solder-melt temperature to further melt the solder between the spaced-apart chip and substrate to electrically join the solder of the chip and the substrate, then introducing formic acid vapor vent to the chamber;
• advancing the heated, joined chip/substrate assembly to a fifth subsequent station, and heating the now pre-assembled chip/substrate assembly to a peak temperature, while vacuuming and then venting the chamber with nitrogen;
• advancing the joined chip/substrate assembly from the fifth station to a sixth station for cooling at ambient or room temperature;
• and
• shuttling the chip/substrate assembly to a final downstream Load/Lock station for unloading the joined chip/substrate assembly from the chamber at the Load/Lock station;
• wherein the first, second, third stations and fourth are each individually heated to a pre-set temperature of from about 150° C. to about 270° C., and wherein the fifth station is heated to a highest peak solder melting temperature of the series of stations, at a pressure of about 760 torr for a period of about 10 to about 300 seconds.

An electronic semiconductor component manufactured by a flux-free, serial thermal processing arrangement for sequentially 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, comprising the steps of:

• loading the pre-assembled chip/substrate 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;
• advancing the pre-assembled chip/substrate into a first treatment chamber or station, and heating the pre-assembled chip/substrate assembly to below solder melt temperature, then holding the first chamber below atmospheric pressure, and then introducing formic acid vapor vent;
• advancing the pre-assembled chip/substrate assembly to a second chamber or station, heating the pre-assembled chip/substrate assembly to a temperature above the melting temperature of the solder, then holding the second chamber at a vacuum, and then introducing a formic acid vapor vent;
• advancing the pre-assembled chip/substrate assembly from the second station to a third chamber or station, heating the pre-assembled chip/substrate assembly to a temperature above the melting point of the solder, then holding a vacuum, and then introducing a formic acid vapor vent to the chamber;
• advancing the pre-assembled chip/substrate assembly from the third station to a fourth station, and heating the pre-assembled chip/wafer assembly at an elevated temperature to further treat the solder between the spaced-apart chip and substrate to electrically join the solder of the chip and the substrate, then introducing formic acid vapor vent to the chamber;
• advancing the heated, joined chip/substrate assembly to a fifth subsequent station, and heating the assembly to a peak solder melt temperature to join melt and join the pre-assembled chip/substrate assembly under a vacuum, then venting the chamber with nitrogen;
• advancing the joined chip/substrate assembly from the fifth station to a sixth station for cooling at ambient or room temperature;
• and
• shuttling the chip/substrate assembly to a final downstream Load/Lock station for unloading the joined chip/substrate assembly from the chamber at the Load/Lock station;
• wherein the first, second, third and fourth stations are each individually heated to a pre-set temperature of from about 150° C. to about 270° C., and at a pressure of about 760 torr for a period of about 10 to about 300 seconds.