The invention discloses a preparation method of low-temperature solderable conductive
copper paste, and belongs to the technical field of
electronic materials. The conductive
copper paste is prepared from the following raw materials: silver-coated
copper powder, an organic carrier, an
antioxidant, a curing agent, an auxiliary agent, a thixotropic agent, a
solvent and an adhesion
enhancer. The design of the composite copper
powder coated with the silver layer on the surface is matched with the graded particle size, and an organic carrier is combined, so that
high conductivity and strong
oxidation resistance under low-temperature curing are realized. The preparation method comprises the following steps: treating the copper
powder by adopting a dipping-
drying process, and
coating the surface of the copper powder with the adhesion
enhancer and the
antioxidant by adopting a chemical method; uniformly mixing the organic carrier, the curing agent, the
solvent and the auxiliary agent; and finally, copper powder and a thixotropic agent are added into the mixed organic carrier, and the low-temperature solderable conductive copper paste is prepared through high-speed dispersion and
grinding of a three-roller
machine. The product can be rapidly cured at 100-180 DEG C, the
sheet resistance is smaller than or equal to 20 m
omega / square, the
welding strength reaches 15 MPa or above, cost is low, production is easy, and wide industrial application value is achieved.