QUALCOMM Incorporated
THERMAL COMPRESSION FLIP CHIP BUMP

Abstract:

A thermal compression flip chip (TCFC) bump may be used for high performance products that benefit from a fine pitch. In one example, a new TCFC bump structure adds a metal pad underneath the TCFC copper pillar bump to cover the exposed aluminum bump pad. This new structure prevents the pad from corroding and reduces mechanical stress to the pad and underlying silicon dielectric layers enabling better quality and reliability and further bump size reduction. For example, a flip chip connection may include a substrate; a metal pad on a contact side of the substrate and a first passivation layer on the contact side of the substrate to protect the metal pad from corrosion.