Abstract: A process monitor test chip and methodology allows process-related manufacturing defects to be quickly identified and isolated. A basic circuit block of a test chip having a number of inverter cells serially connected with a corresponding number of observation points before the input of each inverter cell provides for the inverter cells in the basic circuit block to be probed and thus observed by e-beam technology. Any required number of basic circuit blocks may be serially connected end to end to constitute a chain circuit. Within the test chip itself, a plurality of chain circuits may be connected serially or in parallel to accomplish different testing goals. By controlling an input signal and a control signal of a multiplexing element associated with each chain circuit, the plurality of chain circuits can be forced into a serial connection or a parallel connection.