Test structure measuring inter- and intralayer coupling capacitance of interconnection with subfemtofarad resolution

We present a new test structure measuring inter- and intralayer coupling capacitance parasitic to the same target interconnection with subfemtofarad resolution. The coupling capacitance as well as fringing capacitance measured by the test structure are demonstrated for two-level copper interconnections used in 90-nm technology node. In addition, we demonstrate that the accuracy of layout parameters extraction is improved by nondestructive inverse modeling of a copper interconnect cross-sectional structure, which reproduces the pitch dependence of the measured inter- and intralayer coupling capacitance within about a 1% error.