Atomic force microscopy-induced nanopatterning of Si(100) surfaces

In this. study, we investigate the possibilities of selectively electrodepositing Cu on surface defects created in p-type and n-type Si(100) by scratching the surface with the tip of an atomic force microscope (AFM). Nanosized grooves were produced on Si surfaces with a diamond-coated AIM tip at heavy forces. Cu was electrodeposited on these grooved surfaces from a 0.01 M CuSO4 + 0.05 M H2SO4 electrolyte under various conditions. The results clearly show that defects created on H-terminated p-type Si(100) lead to an enhanced reactivity, i.e., preferential Cu deposition at such defects is possible. However, a much higher degree of selectivity of the deposition is obtained if AFM-induced grooves are produced on surfaces that carry a native oxide layer. The masking effect of this insulator film is demonstrated by selective Cu electrodeposition into scratches on oxide-covered p- and n-type silicon. After an optimization of electrochemical parameters, we achieved the deposition of uniform and well-defined nanostructures. The process presented here opens new perspectives for selective electrodeposition and direct patterning of Si surfaces. (C) 2001 The Electrochemical Society.