Apparatus and method for electrical determination of delamination at one

Abstract

An apparatus and method are presented for electrically determining whether delamination has occurred at one or more interfaces within a semiconductor wafer. The semiconductor wafer includes a test structure formed within dielectric layers upon an upper surface of a semiconductor substrate. The test structure includes an electrically conductive structure, a pair of electrically conductive contact plugs, and a probe pad. The conductive structure is formed within an opening in a first dielectric layer, and is in electrical contact with the upper surface of the semiconductor substrate. The conductive structure is preferably made up of the same vertical stack of layers of selected electrically conductive materials used to form interconnects within the semiconductor wafer. A second dielectric layer if formed over the first dielectric layer and the conductive structure. The pair of electrically conductive contact plugs extend vertically through respective holes in the second dielectric layer. An electrically conductive probe pad is formed upon an upper surface of the second dielectric layer and extends between the pair of contact plugs. Each contact plug is in electrical contact with the probe pad and the electrically conductive structure. During testing, a probe of a measurement device is brought into contact with the probe pad. The measurement device measures the electrical resistance and/or reactance between the probe pad and the semiconductor substrate. The resulting resistance and/or reactance measurement may be compared to an expected resistance and/or reactance value to determine if delamination has occurred at one or more interfaces within the semiconductor wafer.