Figure 1

(a1, a2) AFM topographic images (1 × 1 μm ² ) of a 'raw' CNT obtained with a Pt/Ir and a diamond tip, respectively; (b1, b2) CNT height profile along dotted lines; (c1, c2) corresponding electrical maps; (d1, d2) distribution histograms of resistance values measured in the region marked out by a rectangle on the CNT. The cantilever load-force was about 16 to 80 nN, respectively, for k = 1 to 5 N/m. V _tip-sample = +1 V.