Scanning electron microscope (SEM) image for (a) micrometer size junctions, showing that the defined and (actual) areas of large junctions from left to right are 800 × 800 (680 × 590), 1000 × 1000 (890 × 800) and 2000 × 2000 (1930 × 1820) nm², and for (b) nanometer size junctions, showing that the defined and (actual) areas of small junctions from left to right are 80 × 80 (96 × 72), 100 × 100 (104 × 75), 120 × 120 (160 × 80), and 200 × 200 (214 × 187) nm².