Patent ID: 7439611

Claim:
A circuit board comprising: a flexible insulating substrate, a plurality of conductive wirings formed in line on the flexible insulating substrate, and bumps provided at the end portions of the respective conductive wirings positioned in a region for mounting a semiconductor chip, on which the semiconductor chip can be mounted by bonding electrode terminals formed on the semiconductor chip to the bumps; the circuit board further comprising: an auxiliary conductive wiring positioned at an outermost corner of the region for mounting the semiconductor chip, being adjacent to and outside the outermost conductive wiring, and an auxiliary bump formed on the auxiliary conductive wiring in line with the bumps on the conductive wirings, wherein one end portion of the auxiliary conductive wiring is terminated at a position in the outside vicinity of the auxiliary bump in an outward direction of the region for mounting the semiconductor chip, and the auxiliary conductive wiring is bent at the other end portion positioned inside the auxiliary bump in an inward direction of the region for mounting the semiconductor chip, and connected to an end of an adjacent outermost conductive wiring.