Project/Area Number |
07405029
|
Research Category |
Grant-in-Aid for Scientific Research (A)
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Allocation Type | Single-year Grants |
Section | 一般 |
Research Field |
Composite materials/Physical properties
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Research Institution | Tohoku University |
Principal Investigator |
HIRAI Toshio Institute for Materials Research, High-Temperature Materials Science, Tohoku University Professor, 金属材料研究所, 教授 (50005865)
|
Co-Investigator(Kenkyū-buntansha) |
CHEN Lidong Institute for Materials Research, High-Temperature Materials Science, Tohoku Uni, 金属材料研究所, 助手 (90280883)
OMORI Mamoru Institute for Materials Research, High-Temperature Materials Science, Tohoku Uni, 金属材料研究所, 助手 (30005954)
MASUMOTO Hiroshi Institute for Materials Research, High-Temperature Materials Science, Tohoku Uni, 金属材料研究所, 助手 (50209459)
GOTO Takashi Institute for Materials Research, High-Temperature Materials Science, Tohoku Uni, 金属材料研究所, 助教授 (60125549)
山根 久典 東北大学, 金属材料研究所, 助手 (20191364)
|
Project Period (FY) |
1995 – 1996
|
Project Status |
Completed (Fiscal Year 1996)
|
Budget Amount *help |
¥14,400,000 (Direct Cost: ¥14,400,000)
Fiscal Year 1996: ¥2,500,000 (Direct Cost: ¥2,500,000)
Fiscal Year 1995: ¥11,900,000 (Direct Cost: ¥11,900,000)
|
Keywords | SiO_2 thin film / TiO_2 thin film / optical multilayr / Rugate filter / helicon plzma / functionally graded material / ヘリコンスパッタ / 光学フィルター / SiO_2 / TiO_2 / 薄膜 / 多層膜 |
Research Abstract |
Dielectric multilayres are used for bandpass filters in optical communication and for antireflection coatings in solar cells. In these cases.optical losses should be lowered by smoothing interfaces and reducing defects in films. In a helicon sputtering method, high density plasma can be maintained under a low gas pressure. Sputtering ions keep their kinetic energy due to a long mean-free-pass, which enables one to elongate a target-substrate distance. Therefore less plasma-damaged films having a smooth surface can be obtained. In the present work, silica/titania multilayres or Rugert filter were prepared by helicon sputtering. The structure and optical properties of films were measured. Effect of helicon wave power was studied with a plasma-emission spectrometer. The plasma emission intensity increased with increasing radio frequency (RF) power, but plasma density was almost saturated at more than 100W.Thus the RF power was fixed at 100W.Refractive index of titania film decreased from 2.42 to 2.35 with decreasing total gas pressure, but that of silica film was constant (1.48). Both silica and titania films were amorphous. A silica-titania multilayr whose reflection peak is 800nm was designed. It was confirmed that the multilayr had almost the same transmittance spectrum as that of calculation. A transmission electron micrograph showed that the multilayred films had smooth interface.
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