METHOD FOR ASSEMBLING A HYBRID MICROWAVE INTEGRATED CIRCUIT Russian patent published in 2022 - IPC H05K3/34 

FIELD: microelectronics.

SUBSTANCE: method for assembling a hybrid microwave integrated circuit on a ceramic substrate includes applying solder paste with flux on both sides of the ceramic substrate, placing the ceramic substrate with the reverse side on a metal base, placing mounted passive and active elements of a hybrid integrated circuit on the front side of the ceramic substrate, conducting technological soldering operations of elements of a hybrid integrated circuit providing for preheating, heating to soldering temperatures, actual soldering and cooling, the elements of the hybrid integrated circuit are washed from the flux residues, while the mentioned technological operations on the reverse and front sides of the ceramic substrate are carried out separately. A soldering paste with a flux based on tin-silver-copper is applied to the reverse side of the ceramic substrate, the ceramic substrate is placed with the reverse side on a metal base, the soldering of the reverse side of the ceramic substrate with a metal base is carried out with preheating in a nitrogen medium to a temperature of 170-190°C at a speed of 1.1-1.4°/s, kept at this temperature for 240-420 s, heating to the soldering temperature is carried out in vacuum to a temperature of 250-270°C at a speed of 0.7-0.9 °/s, cooling in a nitrogen medium to a temperature of 70-75 ° C at a rate of 0.3-1.0 °/s, then a soldering paste with a flux based on tin-lead-silver is applied to the front side of the ceramic substrate, mounted passive and active elements of a hybrid integrated circuit are placed, soldering of mounted passive and active elements on the front side is carried out by preheating in a nitrogen medium to a temperature of 150-165°C, exposure at this temperature in a vacuum during 240-420 s, heating to the soldering temperature in vacuum and soldering itself for a given time, cooling to a temperature of 70-75°C at a speed of 0.3-1.0°/s.

EFFECT: invention provides an increase in the reliability and yield of suitable hybrid integrated circuits by improving the quality of the solder joint, ensuring its maintainability, simplifying the method.

3 cl, 1 dwg