New aspects of nanopotentiometry for complementary metal-oxide-semiconductor transistors

Nanopotentiometry is a scanning probe microscopy (SPM) technique providing insight in the actual working behavior of semiconductor devices under opera tion. In nanopotentiometry, a conductive SPM tip is used as a voltage probe in order to measure the distribution of the electrical potential on the cr oss section of an operating device. The information thus provided, is compl ementary to carrier profiling and is a method for the calibration of device simulations, The suitability of alternative SPM techniques for studying ul trashallow devices under operation is examined. Measurements have been carr ied out in deep submicron complementary metal-oxide-semiconductor devices. The impact of the changes in the doping profile on the potential distributi ons has been explored using simulations and experimental results. Due to fu rther improvements in sample; preparation and measurement methodology, the response of the devices to variable bias conditions could be studied in mor e derail. The formation of the conductive channel underneath the gate was i nvestigated and compared to device simulations. (C) 2000 American Vacuum So ciety. [S0734-211X(00)01801-1].