Semiconductor structure for testing vias interconnecting layers of the structure

A wafer for testing a manufacturing process for vias has a large number of vias (millions) formed into strings that have an open circuit resistance if the string contains a defective via and have a resistance of a few thousand ohms if the string is good. A multiplexor circuit is formed on the test wafer and scans the via strings and produces a binary output denoting that the addressed string is good or defective. The addresses are generated off the wafer by a compute and a defective string is readily identified.