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

• Published in: Journal of the Electrochemical Society 2001-09, Vol.148 (9), p.C640-C646
• Main Authors: SANTINACCI, L, DJENIZIAN, T, SCHMUKI, P
• Format: Article
• Language: English
• Subjects: Applied sciences; Cross-disciplinary physics: materials science; rheology; Electrodeposition, electroplating; Electronics; Exact sciences and technology; Materials science; Metals. Metallurgy; Methods of deposition of films and coatings; film growth and epitaxy; Microelectronic fabrication (materials and surfaces technology); Physics; Semiconductor electronics. Microelectronics. Optoelectronics. Solid state devices
• ISSN: 0013-4651; 1945-7111
• DOI: 10.1149/1.1389341

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 AFM tip at heavy forces. Cu was electrodeposited on these grooved surfaces from a 0.01 M CuSO sub 4 + 0.05 M H sub 2 SO sub 4 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 eta -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.