Those various profile artifacts either do not appear or are much smaller if standard flared silicon CD-AFM tips are used. This fact strongly suggests that the root cause is the slenderness/flexibility of the CNT, which results in tip flexing and tip-sample sticking during scans. These tip behaviors are not completely controlled by the AFM control algorithms, which were not originally developed for such flexible tips. CD-AFM2 has a more advanced tip control algorithm than CD-AFM1, so the performance of J-tips on CD-AFM2 was generally better than on CD-AFM1. However, since the instrument is located at a non-NIST facility, we used different tips and samples with CD-AFM2 than with CD-AFM1. Some of the results obtained using a J-tip with CD-AFM2 are shown in Fig. 8.