1. A method of determining a geometrical configuration of an interconnect structure of a test structure, the method comprising: obtaining simulation data correlating capacitance data, resistance data and geometrical configuration data for a plurality of interconnect structures having different geometrical configurations; measuring a capacitance value and a resistance value from the interconnect structure of the test structure; and determining the geometrical configuration of the interconnect structure by comparing the capacitance value and the resistance value to the simulation data.