A multi-stage temperature gradient assembly process for muti-channel T/R module

This paper mainly introduces an eight-channel T/R module packaging process with multiple temperature gradients. The T/R module was achieved through the following processes: 1) Eutectic sintering process of the power amplifier chips by using Au80Sn20 solder preform (Melting point 280 ℃ ). 2) Integrated soldering process of the substrate and connectors by using Sn96.5Ag3Cu0.5 solder preform (Melting point 217 ℃ ). 3) Reflowing process of the surface mount devices and partitions by using Sn63Pb37 solder paste (Melting point 183 ℃). 4) Epoxy bonding process of the bare chips and carriers by using 84-1A conductive adhesive (Curing parameter 170 ℃-30 min). 5) Vacuum soldering process of the power amplifier carriers by using Sn43Pb43Bi14 solder preform (Melting point 154 ℃) and gas phase cleaning process of the module. 6) Wedge and ball bonding process of the substrate and bare chips by using gold and aluminum wire (Bonding temperature: 120 ℃). 7) Laser welding process of the cover plate and shell (Oven parameter: 80 ℃-120 min). The air tightness, epoxy bonding strength and wire bonding strength of the module meet the standard requirements. This module adopted temperature gradients from high to low for assembly to ensure a good ground performance, and used automatic equipments for high-density package to achieve good consistency and high reliability.