Test structure for detecting bonding-induced cracks

Abstract

An integrated circuit having a crack detection structure. A control structure is formed having interleaved electrically conductive layers and non electrically conductive layers in a vertical orientation. Electrically conductive vias are disposed vertically through all of the non electrically conductive layers, which vias electrically connect all of the electrically conductive layers one to another. A test structure is formed having a bonding pad for probing and bonding, with underlying interleaved electrically conductive layers and non electrically conductive layers disposed in a vertical orientation. At least one of the non electrically conductive layers has no vias formed therein, simulating active circuitry under other bonding pads of the integrated circuit. At least one of the interleaved electrically conductive layers of the control structure extends from within the control structure to within the test structure as a sensing layer. The sensing layer immediately underlies the at least one of the non electrically conductive layers in the test structure that has no vias formed therein. Thus, a crack in the at least one of the non electrically conductive layers in the test structure that has no vias formed therein is detectable as a leakage current between the bonding pad of the test structure and a top most electrically conductive layer of the control structure.