A microwave dielectric measurement was performed to study the hydration properties of proteins in solution with a precision network analyzer with high reproducibility within the errors of 0.02 in relative dielectric constant over 2 to 10 GHz. A measurement was carried out for catalase, chymotrypsinogen A, cytochrome C, hemoglobin, peroxidase, lysozyme, myoglobin, ovalbumin, and bovine serum albumin at 20.0 ( 0.01 °C. The hydration properties of protein molecules were evaluated based on the Wagner mixture theory combined with single Debye approximation to the complex dielectric constant of hydrated solutes in the above frequency range. This was used to evaluate the loosely bound water number N w from the single Debye fitting, which gives the relaxation frequency (f c ) of the hydration shell loosely bound and tightly bound water number N s with lower relaxation frequencies than f c . Those hydration numbers were compared with the monolayer water numbers accessible to hydrophobic and hydrophilic exposed atoms, respectively, obtained from the calculation of accessible surface area of each protein structure based on the protein database. The result showed a good agreement both in the ratio and numbers. * To whom correspondence should be addressed. ap * ) a *{2(1φ) a * + (1 + 2 φ) q *}/{(2 + φ) a * +(1φ) q *} (1)

Amorphous diamond-like carbon film prepared by pulsed laser deposition with application of pulsed negative bias voltage High intensity femtosecond laser deposition of diamond-like carbon thin films

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Electron-beam/ultraviolet (UV) exposure technology to produce undercut T-shaped resist cavities with bottom openings as small as 0.15 μm is demonstrated with a novel bilayer resist system for AlInAs/InGaAs high electron mobility transistors operated at the millimeter-wave band. We employed an image reversal resist (AZ5206E) for the top layer and a polydimethyl glutarimide (PMGI) for the bottom layer. The top layer is delineated by UV exposure and the bottom layer is delineated by electron-beam direct writing. These resist layers are developed layer by layer in different content aqueous tetramethyl ammonium hydroxide solution. Resist profiles are extremely well controlled because exposure and development of both layers are completely independent. A reliable overhang structure for metal liftoff, with a 0.15 μm footprint, was obtained. Gate length variation of less than ±10% on a 3-in.-diam InP substrate was successfully accomplished. In addition, an interesting phenomenon was noted. The combination of these two resists leads to an electron-beam sensitivity decrease of PMGI. This phenomenon is closely related to the change of molecular weight distribution in PMGI. The novel bilayer resist system also allows the further improvement of resolution. This would provide a practical means for electron-beam lithography in the nanometer region.

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