UA94328C2 - Method for manufacturing back planes - Google Patents

Abstract

The invention relates to means for manufacturing back planes for radio engineering industry. A method for manufacturing of back planes comprises manufacturing dielectric blanks with holes; thereafter, surfaces of dielectric blanks are prepared to deposit of a thin copper layer, a thin copper layer is deposited in vacuum to surfaces of dielectric blanks and walls of mounting via-holes, pattern of dielectric blanks is formed on the surfaces of dielectric blanks via deposition of photoemulsion; copper layer is deposited surfaces of dielectric blanks and walls of via-holes. Prior to the thin copper layer deposition, surfaces of dielectric blanks are prepared; for this, a number of blanks and curtain portion of waterless formiate of divalent copper are placed in a vacuum chamber, where exhaustion of (1-3)× 10-2 mm of mercury is maintained, dielectric blanks are heated to temperature of 170-180 °C which is maintained during 20 min.; thereafter temperature is increased to 190-200 °C and maintained to finishing process of the thin copper layer deposition, thin layer is deposited on the surfaces of dielectric blanks and walls of via-holes via heating waterless formiate of divalent copper up to evaporation temperature of 180-185 °C, the said waterless formiate is evaporated, forming in such a way a mist of copper formiate which is equally spaced over the vacuum chamber volume and being in contact with surfaces and walls of mounting via-holes of dielectric blanks which are heated to dissociation temperature of divalent copper waterless formiate which equals to 190-200 °C. As a result, copper particles resolve to copper and gases COand H, on the walls of mounting holes and on the surface of dielectric blanks solid copper layer coupled with surfaces of dielectric blanks and their holes which has the same thickness both in the holes and on the surfaces of dielectric blanks. The invention provides improvement of adhesion and deposition of the copper layer to horizontal surfaces and metal plating of small diameters holes of back planes.