The method of junction delineation with thickness fringes in selectively chemical etched transmission electron microscope cross sections is demonstrated on a few examples. Arsenic‐doped source and drain regions of metal‐oxide‐silicon transistors were delineated at a concentration level of about 1×1018cm−3both in the as‐implanted state and after 900 °C annealing. Calibration was performed with one‐dimensional secondary ion mass spectroscopy dopant profiles whereas process simulation was used to examine the experimental two‐dimensional results. The lateral extent of the dopant surface concentration at 1×1019cm−3under the transistor gate after 900 °C annealing corresponded to then+/ntransition region previously detected by scanning tunneling microscopy. Boron and arsenic junctions were simultaneously delineated in a bipolar transistor.