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Display Omitted We investigated the surface tribological properties of two release agents.The friction and adhesion forces were measured separately.Two kinds of release agents were shown different friction and adhesion forces.Our tribological method of evaluating the properties is shown to be effective. The adhesive and friction forces generated in releasing a mold from a resin in the presence of a release agent was investigated by using a TriboIndenter. We investigated the surface tribological properties of two ultraviolet-nanoimprint-lithography release agents, Optool DSX and trichloro(tridecafluoro-octyl)silane C8H4Cl3F13Si] (F13), to elucidate the mold-release mechanism. For both release agents, we measured the friction and adhesive forces acting on the substrate. The friction force of Optool DSX was found to be lower than that of F13, whereas F13 showed a lower adhesive force than Optool DSX. Our previous results revealed that the durability of Optool DSX as a release agent was better than that of F13. Examining our previous and current results, we saw that the trends in the contact angle and the number of defects with increasing imprinting counts coincide with the trends in the friction and adhesive forces, respectively, of the release agents. Our method of evaluating the surface properties of release agents in two kinds of tests is shown to be effective.

Nowadays, industrial products are downsized, and the structure of materials is controlled with the nanometer precision, and it becomes very important to measure the mechanical properties of local area of bulk material. Especially the hardness and the elastic modulus are important mechanical properties. The orientation dependence of hardness and reduced modulus of single crystal sapphire surface was investigated by nanoindentation. The conventional technique to measure the hardness of materials using an optical micrometer cannot evaluate mechanical properties of a local region of several µm or less. However, nanoindentation can measure mechanical properties of very small surface area of materials, and is expected to detect the micro structure dependence of mechanical properties. Nanoindentation uses very small indenter made of diamond, and measures the indentation depth. The measured depth is converted to the indented area size using the area function. The area function of the indenter can be obtained using a standard material (fused quartz) in advance. Therefore nanoindentation can measure the indented area size without using an optical micrometer. In this report, it was shown that the nanoindentation could detect the structure dependence of mechanical properties of materials. The specimen was a single crystal sapphire with c - axis surface, and the indenter was Berkovich type diamond tip. It was confirmed that the nanoindentation hardness was the lowest, and the reduced modulus was the largest, when the ridge line of indenter was oriented to the m - axis of single crystal. The nanoindentation could detect the structure dependence of a local area of mechanical properties materials.

The adsorption of individual acetylene molecules at a Pd(1 1 1) surface has been studied with scanning tunneling microscopy (STM) at 4.7 K. The adsorbed acetylene molecules appear in the STM images as a combination of a protrusion and a pair of depressions. To determine the adsorption site and configuration of the molecule, we performed rotational manipulation of the molecule by injecting tunneling electrons into the molecule as well as performing atomically resolved STM imaging. The STM images revealed that the molecules have a total of six equivalent adsorption orientations on Pd(1 1 1), indicating three equivalent rotational states on two (both fcc and hcp) 3-fold hollow adsorption sites. From the atomically resolved STM images of the surface with a monatomic step edge, we have distinguished the two types of 3-fold hollow sites and confirmed that the fcc site is more stable than the hcp site at a low temperature.

Inelastically tunneled electrons from a scanning tunneling microscope (STM) were used to induce vibrationally mediated motion of a single cis-2-butene molecule among four equivalent orientations on Pd(110) at 4.8 K. The action spectrum obtained from the motion clearly detects more vibrational modes than inelastic electron tunneling spectroscopy with a STM. We demonstrate the usefulness of the action spectroscopy as a novel single molecule vibrational spectroscopic method. We also discuss its selection rules in terms of resonance tunneling.