Multilayer laminated wiring

Claim 1

IN A METHOD FOR PRODUCING LAMINATED CIRCUIT BOARDS, THE STEPS OF: APPLYING TO AT LEAST ONE SURFACE OF EACH OF A NUMBER OF SUBSTANTIALLY CURED THERMOSETTING PLASTIC LAMINAS A PLURALITY OF CONDUCTORS HAVING ENLARGED PORTIONS FORMING TERMINAL PADS AT PREDETERMINED LOCATIONS; SECURING TO THE OPPOSITE SURFACE OF EACH LAMINA A SHEET OF SUBSTANTIALLY NONCURED THERMOSETTING PLASTIC FOR INTERPOSITION BETWEEN EACH PAIR OF ADJACENT LAMINAS; MAKING FIRST, LARGER APERTURES THROUGH SOME OF SAID LAMINAS AND THE SHEETS SECURED THERETO AT LOCATIONS CORRESPONDING TO THOSE OF SAID PADS ON ANOTHER OF SAID LAMINAS; FORMING A STACK BY ALIGNING SAID SOME LAMINAS AND SHEETS, WITH SAID FIRST APERTURES IN REGISTRY WITH SAID PADS AND ADDING THE REMAINING LAMINAS AND SHEETS SO THAT SAID FIRST APERTURES FORM ACCESS APERTURES EXTENDING FROM ONE SURFACE OF THE STACK TO SAID TERMINAL PADS, SAID PADS FORMING THE BOTTOM OF AN ACCESS APERTURE; BONDING SAID LAMINAS TO ONE ANOTHER BY MEANS OF SAID INTERPOSED SHEETS AND APPLICATION OF HEAT AND PRESSURE TO FORM A LAMINATED STRUCTURE HAVING CONDUCTORS AND TERMINAL PADS EMBEDDED AT DIFFERENT LEVELS OF DEPTH, WITH AN ACCESS APERTURE CONNECTING THE PADS WITH ONE OUTE SURFACE OF THE STRUCTURE; AND SUBSEQUENTLY FORMING A SMALLER CONTINUING SECOND APERTURE THROUGH SAID PADS AND THE REMAINING BONDED LAMINAS TO THEREBY PRODUCE AN OPENING THROUGH THE PAD WHICH INTERCONNECTS THE TWO EXTERNAL SURFACES OF THE FINISHED LAMINATED CIRCUIT BOARD.