Integrating an Ultramicroelectrode in an AFM Cantilever:  Combined Technology for Enhanced Information

Abstract

We present a novel approach to develop and process a microelectrode integrated in a standard AFM tip. The presented fabrication process allows the integration of an electroactive area at an exactly defined distance above of the end of a scanning probe tip and the subsequent remodeling and sharpening of the original AFM tip using a focused ion beam (FIB) technique (See ref 1 for patent information). Thus, the functionality of scanning electrochemical microscopy (SECM) can be integrated into any standard atomic force microscope (AFM). With the demonstrated approach, a precisely defined and constant distance between the microelectrode and the sample surface can be obtained, alternatively to the indirect determination of this distance usually applied in SECM experiments. Hence, a complete separation of the topographical information and the electrochemical signal is possible. The presented technique is a significant step toward electrochemical imaging with submicrometer electrodes as demonstrated by the development of the first integrated frame submicroelectrode.

Métodos para fabricação de microeletrodos visando a detecção em microambientes

“…38,95,[125][126][127] O processo de litografia, utilizado na maioria dos casos de microfabricação, está baseado na transferência de uma cópia de um padrão mestre, de um determinado material, para um substrato sólido. Um exemplo é a fabricação de microeletrodos cônicos a partir do desgaste de um substrato de Si, seguido pela deposição de filmes finos de SiO 2 , Pt e Si 3 N 4 .…”

Peer Reviewed: Atomic Force Microscopy Probes Go Electrochemical

“…Thus, microfabrication technologies represent an attractive way forward. Kranz and co-workers have made progress toward this goal by first sputter-coating a conventional silicon nitride AFM probe with a 100-300-nm-thick layer of gold, and then depositing an ~800-nm-thick layer of silicon nitride using plasmaenhanced chemical vapor deposition (42). Successive millings using a focused ion beam sharpen and redefine the geometry of the AFM tip so that a gold microring electrode is formed around the base of the AFM tip.…”

Simultaneous imaging of the topography and electrochemical activity of a 2D carbon nanotube network using a dual functional L-shaped nanoprobe

“…8 However, in the electrochemical current signal, mixed information regarding the local activity and the tip-to-sample distance remains an issue. Diverse approaches, including shear force, 9 intermittent contact (IC)-SECM, 10 combined SECM-scanning ion conductance microscopy (SICM), 11 and SECM-AFM, [12][13][14][15] have been applied to enable fine distance control of electrochemical scanning probes. Recently, double-barrel carbon nanoprobes (DBCNPs) were developed for combined SECM-SICM and were used for simultaneous topographical and electrochemical imaging of a variety of substrates such as microelectrodes, nanoporous membranes, and PC12 cells.…”