Electrochemical modification of surface STRUCTURE

FIGURE 2.11. Patterns formed on a Au(l 11) surface after removal of half a monolayer of Au atoms within 20 ms (top) and 20 ts (bottom). 

FIGURE 2.12. Energetics and kinetics of a thermal and an electrochemical reaction. (See color insert.) 

The lateral extension of the surface area whose structure can be affected in this way will be confined to the vicinity of the tip. The electrochemical fabrication of microstructures by approaching a tool to the surface is, however, limited by the nonuniform current distribution in this case, as illustrated in Fig. 2.14, and the resulting structure is rather disappointing. This problem may be overcome by applpng short voltage pulses instead of a DC voltage, as shown in Fig. 2.15 [14]. If initiation of electrochemical dissolutionrequires 

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