Method of making a multi-layer circuit board

摘要

To provide a simplified method of making a multi-layer circuit board capable of observing a high density surface mounting of electronic parts, a method is provided for making a multi-layer circuit board including a first film (A) and at least two more films, second and third films (B and C), each being made of thermoplastic polymer capable of forming an optically anisotropic melt phase. The first film (A) has a low melting point (Tm 1 ), and the second and third films (B and C) have respective melting points (Tm 2 B and Tm 2 C) higher than the melting point (Tm 1 ) of the first film (A). And at least one of the second and the third films have a circuit pattern thereon. The first to third films (A to C) are thermo compressed together with the first film (A) interposed between the second and third films (B and C). The method includes causing at least one of the circuit patterns (D) on one of the second and third films (B and C) to contact an opposing surface of the other of the second and third films (B and C) through the first film (A) during the thermo compression bonding of the first to third films (A to C).