Method for manufacturing embedded trace substrate

A method for manufacturing an embedded trace substrate, the method comprising:

• preparing a film;
• arranging a first electrode pad and a second electrode pad at a peripheral edge of a first main surface of the film along a first direction so as to be parallel to each other and spaced from each other;
• forming, on the first main surface of the film, a circuit including a conductive wire obtained by coating a thin metal wire with an insulating coating, the circuit having a functional portion having an arbitrary pattern, a first wiring portion led out from one end of both ends of the functional portion to an outside of the functional portion, a second wiring portion led out from another end of both ends of the functional portion to the outside of the functional portion, a first end portion extending in the first direction from the first wiring portion so as to partly overlap the first electrode pad and the second electrode pad, and a second end portion extending along the first end portion from the second wiring portion so as to partly overlap the first electrode pad and the second electrode pad, the circuit being formed by embedding the functional portion, the first wiring portion, the second wiring portion, and sections of the first end portion and the second end portion not overlapping the first electrode pad and the second electrode pad in the first main surface of the film using an ultrasonic welding machine;
• removing the insulating coating of the conductive wire located on the first electrode pad and electrically connecting the thin metal wire that is exposed to the first electrode pad;
• and
• removing the insulating coating of the conductive wire located on the second electrode pad and electrically connecting the thin metal wire that is exposed to the second electrode pad, wherein
• one end connected to the first wiring portion out of both ends of the first end portion and one end connected to the second wiring portion out of both ends of the second end portion are located at positions sandwiching the first electrode pad and the second electrode pad in plan view,
• the ultrasonic welding machine includes a horn that melts a contact surface of the film with the conductive wire by applying ultrasonic vibration and that embeds the conductive wire into the first main surface of the film, and the conductive wire to be continuously drawn out from a tip of the horn onto the first main surface of the film through an inside of the horn, and
• the first end portion and the second end portion have a length for absorbing a positional deviation of the first electrode pad and the second electrode pad in the first direction relative to the circuit.

A method for manufacturing an embedded trace substrate, the method comprising:

• preparing a film;
• arranging a first electrode pad, a second electrode pad, a third electrode pad, and a fourth electrode pad at a peripheral edge of a first main surface of the film along a first direction so as to be parallel to each other and spaced from each other;
• forming, on the first main surface of the film, a first circuit including a first conductive wire obtained by coating a thin metal wire with an insulating coating, the first circuit having a first functional portion having an arbitrary pattern, a first wiring portion led out from one end of both ends of the first functional portion to an outside of the first functional portion, a second wiring portion led out from another end of both ends of the first functional portion to the outside of the first functional portion, a first end portion extending in the first direction from the first wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, and a second end portion extending along the first end portion from the second wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, the first circuit being formed by embedding the first functional portion, the first wiring portion, the second wiring portion, and sections of the first end portion and the second end portion not overlapping the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in the first main surface of the film using an ultrasonic welding machine;
• forming, on the first main surface of the film, a second circuit including a second conductive wire obtained by coating a thin metal wire with an insulating coating, the second circuit having a second functional portion having an arbitrary pattern, a third wiring portion led out from one end of both ends of the second functional portion to an outside of the second functional portion, a fourth wiring portion led out from another end of both ends of the second functional portion to the outside of the second functional portion, a third end portion extending in the first direction from the third wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, and a fourth end portion extending along the third end portion from the fourth wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, the second circuit being formed by embedding the second functional portion, the third wiring portion, the fourth wiring portion, and sections of the third end portion and the fourth end portion not overlapping the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in the first main surface of the film using an ultrasonic welding machine;
• removing the insulating coating of the first conductive wire located on the first electrode pad and electrically connecting the thin metal wire that is exposed to the first electrode pad;
• removing the insulating coating of the first conductive wire located on the second electrode pad and electrically connecting the thin metal wire that is exposed to the second electrode pad;
• removing the insulating coating of the second conductive wire located on the third electrode pad and electrically connecting the thin metal wire that is exposed to the third electrode pad;
• and
• removing the insulating coating of the second conductive wire located on the fourth electrode pad and electrically connecting the thin metal wire that is exposed to the fourth electrode pad, wherein
• one end connected to the first wiring portion out of both ends of the first end portion, one end connected to the second wiring portion out of both ends of the second end portion, one end connected to the third wiring portion out of both ends of the third end portion, and one end connected to the fourth wiring portion out of both ends of the fourth end portion are located on a same side with respect to the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in plan view,
• in the forming of the first circuit, the ultrasonic welding machine includes a horn that melts a contact surface of the film with the first conductive wire by applying ultrasonic vibration and that embeds the first conductive wire into the first main surface of the film, and the first conductive wire to be continuously drawn out from a tip of the horn onto the first main surface of the film through an inside of the horn,
• in the forming of the second circuit, the ultrasonic welding machine includes the horn that melts a contact surface of the film with the second conductive wire by applying ultrasonic vibration and that embeds the second conductive wire into the first main surface of the film, and the second conductive wire to be continuously drawn out from the tip of the horn onto the first main surface of the film through the inside of the horn, and
• the first end portion, the second end portion, the third end portion, and the fourth end portion have a length for absorbing a positional deviation of the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in the first direction relative to the first circuit and the second circuit.

A method for manufacturing an embedded trace substrate, the method comprising:

• preparing a film;
• arranging a first electrode pad, a second electrode pad, a third electrode pad, and a fourth electrode pad at a peripheral edge of a first main surface of the film along a first direction so as to be parallel to each other and spaced from each other;
• forming, on the first main surface of the film, a first circuit including a first conductive wire obtained by coating a thin metal wire with an insulating coating, the first circuit having a first functional portion having an arbitrary pattern, a first wiring portion led out from one end of both ends of the first functional portion to an outside of the first functional portion, a second wiring portion led out from another end of both ends of the first functional portion to the outside of the first functional portion, a first end portion extending in the first direction from the first wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, and a second end portion extending along the first end portion from the second wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, the first circuit being formed by embedding the first functional portion, the first wiring portion, the second wiring portion, and sections of the first end portion and the second end portion not overlapping the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in the first main surface of the film using an ultrasonic welding machine;
• forming, on the first main surface of the film, a second circuit including a second conductive wire obtained by coating a thin metal wire with an insulating coating, the second circuit having a second functional portion having an arbitrary pattern, a third wiring portion led out from one end of both ends of the second functional portion to an outside of the second functional portion, a fourth wiring portion led out from another end of both ends of the second functional portion to the outside of the second functional portion, a third end portion extending in the first direction from the third wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, and a fourth end portion extending along the third end portion from the fourth wiring portion so as to partly overlap the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad, the second circuit being formed by embedding the second functional portion, the third wiring portion, the fourth wiring portion, and sections of the third end portion and the fourth end portion not overlapping the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in the first main surface of the film using an ultrasonic welding machine;
• removing the insulating coating of the first conductive wire located on the first electrode pad and electrically connecting the thin metal wire that is exposed to the first electrode pad;
• removing the insulating coating of the first conductive wire located on the second electrode pad and electrically connecting the thin metal wire that is exposed to the second electrode pad,
• removing the insulating coating of the second conductive wire located on the third electrode pad and electrically connecting the thin metal wire that is exposed to the third electrode pad;
• and
• removing the insulating coating of the second conductive wire located on the fourth electrode pad and electrically connecting the thin metal wire that is exposed to the fourth electrode pad, wherein
• one end connected to the first wiring portion out of both ends of the first end portion and one end connected to the second wiring portion out of both ends of the second end portion are located on a same side with respect to the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in plan view,
• one end connected to the third wiring portion out of both ends of the third end portion and one end connected to the fourth wiring portion out of both ends of the fourth end portion are located on a same side with respect to the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in plan view,
• the one ends of the third end portion and the fourth end portion and the one ends of the first end portion and the second end portion are located at positions sandwiching the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in plan view,
• in the forming of the first circuit, the ultrasonic welding machine includes a horn that melts a contact surface of the film with the first conductive wire by applying ultrasonic vibration and that embeds the first conductive wire into the first main surface of the film, and the first conductive wire to be continuously drawn out from a tip of the horn onto the first main surface of the film through an inside of the horn,
• in the forming of the second circuit, the ultrasonic welding machine includes the horn that melts a contact surface of the film with the second conductive wire by applying ultrasonic vibration and that embeds the second conductive wire into the first main surface of the film, and the second conductive wire to be continuously drawn out from the tip of the horn onto the first main surface of the film through the inside of the horn, and
• the first end portion, the second end portion, the third end portion, and the fourth end portion have a length for absorbing a positional deviation of the first electrode pad, the second electrode pad, the third electrode pad, and the fourth electrode pad in the first direction relative to the first circuit and the second circuit.