PROCESS OF MANUFACTURE OF TWO-SIDE PRINTED CIRCUIT BOARDS FROM GLASS CLOTH- BASED LAMINATE Russian patent published in 1995 - IPC

FIELD: radio engineering. SUBSTANCE: process includes drilling of holes in unfoiled substrate of glass cloth-based laminate, preparation of substrates for metallization in acidic solution containing oxide of hexavalent chromium for the course of 1-5 min at 20-60 C. Then adhesive sublayer and copper sublayer 0.2-0.5 μm thick are applied during one vacuum cycle by thermal or magnetron evaporation of corresponding metal. Subsequent formation of mask opposite to pattern of circuit is conducted over copper sublayer on both sides by method of dry offset printing with use of alkali-removable paint. Later copper is grown over current conductive pattern by electroplating, protective coat is removed, etching of space sections and conservation of surface of printed circuit board are performed. EFFECT: increased quality and productivity.