Atomic force microscopy combined with a quartzcrystal microbalance has been developed for in situ observation of the morphology and mass change at the liquid/solid interface in an electrolytic solution. The Ag electrodeposition on a Pt thin film from aqueous solutions of H 2 SO 4 , Na 2 SO 4 , and Ag 2 SO 4 has beer observed by this novel instrument. Pt thin film is evaporated on the surface of the quartz-crystal resonator that oscillates at its resonance frequency. The mass change of the Pt film under the electrochemical reaction can be measured by detecting the frequency change of the quartzcrystal resonator. Large crystals were distributed on the Pt surface in clumps. The mass change measured by the microbalance technique agrees not only with that calculated from the integrated charge obtained by cyclic voltammetry but also that estimated from the topographical image. With this novel technique, the deposited substance on the Pt surface could be identified as Ag, not a complex mixture of platinum oxides.It is important to study the solid-liquid interface for understanding the complicated electrochemical reaction on the electrode surfaces. Scanning tunneling microscopy (STM) and atomic force microscopy (AFM) can be used to observe the surface structures in the various environments such as vacuum, air, gas, and liquid. In particular, the application in the liquid electrolyte opened the door to electrochemical investigation. Many groups have reported electrochemistry on the surface such as the oxidation [1, 2], dissolution [3,4], and deposition phenomena [5][6][7]. However the microscopic information using AFM or STM shows only surface morphology. Thus it is not sufficient for understanding the complicate surface reaction. Furthermore, it is difficult to confirm if such local information represents the entire surface phenomena. Thus these microscopes must be combined with another surface analytical method. The quartz-crystal microbalance (QCM) is an extremely sensitive sensor, measuring mass changes in the nanogram range. It comprises a piezoelectric quartz crystal upon which foreign masses are attached by some means. The resonant frequency of the quartz crystal depends on the magnitude of the foreign mass [8]. The QCM is employed widely to monitor the vacuum deposition rate of the thin films and the gas analysis [9][10][11][12]. Even in the electrolytic solution, the QCM can be used as the in situ electrogravimetry under controlled electrochemical condition [13][14][15][16].In this paper, we describe the development of the combined AFM-QCM system and preliminary results concerning simultaneous observation of the morphology and mass change in the electrolytic solution. The processes of Ag electrodeposition on a Pt thin film are observed with this novel instrument. The mass change for Ag deposition is discussed and compared with the QCM result, the calculation from the total charge of voltammetry and the estimate from AFM topographical image. ExperimentThe AFM utilized in this experiment was made by us [17]. The su...

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In this report, a micro capillary capturing probe based on the surface tension of water is described. This probe is composed of a capillary of glass, small solenoids, and a micro magnetic piston. The quick reciprocating motion of the magnetic piston which is accelerated by solenoids current can push and pull the water in the capillary. At the end of the capillary, the water drop can grow to reach the small object on the surface, contain it with the help of surface tension, and retract into the capillary. The basic principle and design will be discussed, and the experimental results of capturing small objects will be demonstrated. We successfully implement this active probe into our miniature precise robot for surface clearing operation.

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