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Accuracy of extracting ultra-low contact resistivity by the end-resistance method is evaluated. As the contact length becomes smaller than the transfer length, the end-resistance approaches the contact resistance, and the error decreases with the reduction of contact length and contact resistivity. The contact resistivity lower than $10^{-9}\Omega-\mathrm{c}\mathrm{m}^{2}$ can be extracted with accuracy lower than $3\times 10^{-10}\Omega-\mathrm{c}\mathrm{m}^{2}$. This end-resistance method is verified by self-aligned transmission line model test structure. Statistic analysis of the distribution of contact resistance and the uniformity of the contact interface are also demonstrated.

In this study, a two-dimension array of InGaAs photodiode with 0.9~1.7nm absorption wavelength was presented. By using the characteristic of wide wavelength range in InGaAs material, we designed several active regions in our novel devices for inducing expected photocurrent. While the distances between light source and these several equal-area active regions increases, we found the current generated in photodiode decreases non-linearly. Furthermore, this device was applied on detecting skin physiology, when the tungsten bulk light source penetrated through skin and was absorbed by photodiode, there had individual different currents in each equal-area active regions, and the relationship between photocurrent and moisture in skin will be interpreted.

Bilayer systems have many important and emerging applications. In this paper, a bilayer system composed of a relatively stiff piezoelectric thin film bonded to an elastomeric thick substrate of a compliant material is studied. The couplings among elastic, electric and thermal fields are considered, when the bilayer system is subjected to a temperature variation, and the piezoelectric thin film is subjected to an electric potential difference between the top and bottom surfaces. An exact solution for stress distribution is derived, which takes account of the influence of the interface between the two components. Numerical results are presented and discussed.

The bending of piezoelectric bimorph plates subject to electric and thermal loadings is investigated. Based on the constitutive equations for the generalized plane stress problems of piezoelectric materials, the stresses and the electric displacements of piezoelectric bimorph plates with different configurations are obtained by virtue of Kirchhoff's hypothesis and Saint-Venant's hypothesis. Analytical expressions for the deflection of piezoelectric bimorph cantilever as an actuator are obtained.

A thermal driving and piezoresistive sensing MEMS cantilever resonator has been proposed and developed to construct trace gas detection sensors. The problem of integrating vibration structure, transducers and electric elements is the main concern in the design and fabrication of the resonator. In this paper, the parameters and the configuration of the resonator are discussed, the fabrication process and the test results are presented. Finite Element Analysis (FEA) has been carried out to optimize the configuration of the resonator to obtain high sensitivity and efficiency with a uniform temperature distribution that is propitious to the function of the gas sensing material. The fabrication process is based on direct bonding silicon-on-insulator (SOI) wafer and inductive coupled plasma (ICP) etching technology, which conciliate the semiconductor processes and the micromaching processes, and provide precise control of the resonator parameters. The experimental test results of the fabricated resonator agreed well with the calculation and simulation results and demonstrated that the proposed resonator was qualified to construct trace gas detection sensors.

Nano drug delivery system (nano-DDS) is a new medical technology. We studied medical use used by about 7 [nm] ferromagnetic fluids. We searched good energy condition of ferrofluid contrast medium radiograph image used by SPring-8 synchrotron radiation X-ray. As results, in case of low photon energy 15.0 [KeV] ( lambda = 0.8 Aring). We showed ferrofluid in Acryl amid gel and taro leaf and mugwort. #1. We found Low photon energy could show vascular tissue and ferrofluid distribution respectively. In case of medium photon energy 20.0 [KeV] ( lambda = 0.6 Aring). We observed ferrofluid in rat ear lobe and rat stomach and rat foot. #2. We found medium photon energy could see several organizations by changing exposure. In case of high photon energy 25.0 [KeV] ( lambda = 0.5 Aring). We showed ferrofluid in chicken egg and pork. #3. We found high proton energy was suitable for observing ferrofluid distribution in plain organization, but was not suitable for observing ferrofluid distribution in complicate organization.

Nano-size magnetic magnetide is considered important for various medical applications. Dynamic motion of the magnetic particle is investigated in two essential models from a theoretical point of view. One is a drag model of the magnetic particle in an artery. The second is a pull model towards the surface of artery. Threshold conditions of external variables are obtained by dimensional analysis. On the basis of all these results, it is concluded that the movement of magnetic fluids can be controlled by external magnetic fields in blood vessels.

In this study, a new manufacturing method of magnetite nanoparticles coated SiO2 amorphous film was proposed. Using the improved liquid phase precipitation method, magnetic nanoparticles can be coated with by the reaction of Na2SiO3 and HCl. The coated SiO2 amorphous film is about 2 nm in thickness. The composite nanoparticles coated SiO2 has good magnetic properties and ability to resist high temperature oxidation.

Dynamic behaviors of nano-scale magnets in biomaterials are observed under external magnetic fields. Although magnetic nano-particles have been proposed for use as biomedical purposes, the interactions between the coat of the magnet and the solvent molecules are not so clear. Therefore basic knowledge on information of the dynamic movement in various materials should be accumulated. Using strong photon beams in SPring-8 facility, we trace movement of magnetic fluid and investigate the response of the nano-scale magnets under external magnetic fields in various materials. In this paper, we show results of the observation in agarose gel, eggs, leaf of plant, and oil. Finally it is shown that one can calculate the velocity of a magnetic cluster of 0.5 mm size from a theoretical point of views, and obtain a good agreement with the experimental data in oil. On the basis of all these results, it is concluded that the movement of magnetic fluids can be precisely controlled by external magnetic fields in various materials.