Figure 10.

Scanning Auger nanoprobe analysis on friction-induced mesa surface. (a) The elemental composition of the friction-induced mesa and original silicon substrate. The lower left insert shows the SEM image of the tested mesa. (b) Oxygen atomic concentration distribution on four different surfaces: original silicon, original mesa, mesa etched in 10 wt.% HF solution for 3 min, and mesa etched in 10 wt.% HF solution for 3 min and then in 20 wt.% KOH + IPA solution for 2 min.