The surfaces of materials possess unique characteristics that may be applied to create novel functional properties. Our research seeks to create nanostructured surfaces and thin films with novel electronic/magnetic functions. We also pursue experimental and theoretical analyses of the processes by which such surfaces and thin films for explore potential applications in advanced devices and systems.

Our current research involves the following projects:
(1) Creating nanostructured surfaces and thin films with novel electronic/magnetic functions
Using electrochemical processing, such as electrochemical and electroless deposition processes, electrochemical etching, and self organized organic monolayers, we are developing new processes to fabricate nanostructured surfaces. For nanostructuring, such as patterned deposition, photolithography, electron beam lithography, and nano imprinting, lithography is used to obtain arrayed nanodots, high aspect ratio pores, and so on.
(2) Analysis and modeling of fabrication process of nanostructures at the solid/liquid interface
Ex situ and in situ analyses of reaction processes; computer simulations of processes using molecular orbital (MO) and density functional theory (DFT) approaches; developing new methods to assess the structural and functional properties of nanostructured surfaces at the nanometer scale, primarily by scanning probe microscopy. SPM includes scanning tunneling microscopy (STM), atomic force microscopy (AFM), scanning surface potential microscopy (SPoM), tunneling AFM (TAFM), and magnetic force microscopy (MFM).
(3) Developing advanced devices and systems
Applying the functional surfaces and thin films developed above makes it possible to devise advanced devices, including ordered arrays of magnetic nanodots, so-called "patterned media" for ultra-high-density data storage devices, picoliter-volume glass tube arrays for micro reactors, and highly-sensitive sensing devices for X-ray imaging and immunoassays.
(4) Analysis of Si wet device processes; developing new nanofabrication processes
Wet (chemical) processes have played a key role in Si device manufacturing, and a precise process has now been developed. However, certain mechanisms, including reactions at the solid/liquid interface, have yet to be fully understood. Using the analytical approaches described above, we are investigating Si device processes, including the preparation of ultra-clean surfaces, and the nanostructuring of Si wafer surfaces to achieve an atomistic understanding of silicon surface chemistry under device processing conditions.

Fig.1

Fig.1 Scanning Electron Microscopy (SEM) image of the CoPt ferromagnetic nanodot array fabricated by electrochemical deposition and nano imprinting lithography. This is used for ultra-high-density magnetic data storage devices.

Fig.2

Fig. 2 SEM image of picoliter-volume glass tube array for the application of various microreactors and systems. The diameter of each tube is 10 micrometer. The thick white rod at the right hand side of the image is a human hair.