Test structure to monitor the effects of polysilicon pre-doping

摘要

Various embodiments of a test circuit and methods of fabricating and using the same are provided. In one aspect, a test circuit includes a semiconductor substrate and a mask thereon that has an opening to enable impurity doping of selected portions of the test circuit. A plurality of circuit devices are provided on the substrate that have respective active regions positioned at staggered known distances from the mask opening. Each of the plurality of circuit devices has a gate electrode that extends to the opening and has a first impurity region of a first conductivity type and a second impurity region of a second and opposite conductivity type. Where the predicted on-state output current of a given circuit device exceeds an actual output current of the given circuit device, there is indication of an overlap between the first and second impurity regions of the gate electrode of the given device.