Grant-in-Aid for Scientific Research (B).
|Allocation Type||Single-year Grants|
Electronic materials/Electric materials
|Research Institution||YAMANASHI UNIVERSITY|
NAKAGAWA Yasuhiko FACULTY OF ENGINEERING, YAMANASHI UNIVERSITY PROFESSOR, 工学部, 教授 (50006277)
KAKIO Shoji FACULTY OF ENGINEERING, YAMANASHI UNIVERSITY ASSOCIATE RESERCHER, 工学部, 助手 (70242617)
|Project Period (FY)
1998 – 2000
Completed(Fiscal Year 2000)
|Budget Amount *help
¥7,400,000 (Direct Cost : ¥7,400,000)
Fiscal Year 2000 : ¥2,300,000 (Direct Cost : ¥2,300,000)
Fiscal Year 1999 : ¥2,000,000 (Direct Cost : ¥2,000,000)
Fiscal Year 1998 : ¥3,100,000 (Direct Cost : ¥3,100,000)
|Keywords||phase grating / surface acoustic wave / microlens / tantalum pentoxide single crystal / acousto-optic effect / linear type rapid thermal annealing / Ta_2O_5薄膜 / SAWアシスト法 / Tα_5O_5薄膜 / 2次元位相格子 / 光弾性定数|
Results got by this study are as follows.
(1) The discovery of the phenomenon of which the photoelasticity is emphasized.
Physical property such as photoelastic constant, film thickness, refractive index increases, when surface acoustic wave standing wave is beforehand excited in thin film preparation by sputtering technique. As the result, the efficiency of the optical modulator of the Bragg diffraction system increased at about 6 times.
(2) The proposal of way of making of a thin film phase grating by the surface acoustic wave assist.
A thin film phase grating is easily formed, when a thin film is established, while surface acoustic wave standing wave is beforehand excited on the substrate. The change of the film thickness is about 1.78% The refractive index variation is about 12.5% It is very big. Dielectric constant of the substrate surface changes by the external electric field of surface acoustic wave in period period of standing wave, and the difference occurs by it in the molecular
adhesion. The spatial variation occurs at film thickness and refractive index as a result.
(3) Preparation and application of the two-dimensional phase grating.
Using orthogonalizing surface acoustic wave standing wave, the two-dimensional phase grating was made. Very accurately placed dot is formed, and the ideal lattice can be easily formed. One piece became an ideal thin film lens, and the application possibility to the ultra microlens was obtained.
(4) The proposal of light polarization control element which effectively utilized the surface acoustic wave power.
High-efficient light tunable filter was proposed. The frequency band is about 0.5MHz. It is available for the light multiplex communication. In addition, it was shown that it was improved at the efficiency, if the Lamb wave is excited in order to increase the overlap area of light wave and surface acoustic wave.
(5) The preparation of the Ta_<>O_5 single crystal thin film by linear type rapid thermal annealing.
It was shown that it proposed linear type rapid thermal annealing and can also make single crystal thin film in the isotropic substrate. Using this, it succeeded in the preparation of the Ta_2O_5 single crystal thin film. Made Ta_2O_5 thin film shows large birefringence. It was shown to be applicable for new function optical device such as memory and optical switching, because it was a ferroelastic and ferroelectric thin film. Less