2001 Fiscal Year Final Research Report Summary
High-functional Superconducting Tunnel Junction fabricated by Electron Beam Excited Plasma Ion Plating Method
| Project/Area Number |
12650316
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Electronic materials/Electric materials
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| Research Institution | Yamaguchi University |
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Principal Investigator |
MOROHASHI Shin'ichi Yamaguchi University Faculty of Engineering Professor, 工学部, 教授 (20304488)
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| Co-Investigator(Kenkyū-buntansha) |
NOGUCHI Takashi National Astronomical Observatory of Japan. Nobeyama Radio Observatory Associate Professor, 野辺山宇宙電波観測所, 助教授 (90237826)
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| Project Period (FY) |
2000 – 2001
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| Keywords | Superconducting Tunnel Junction / High-vacuum EB Evaporation / Facing Targets Sputtering / X-ray Detector / Photon Detector |
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| Research Abstract |
It is important to raise the tunneling efficiency of quasiparticles generated by incident X-ray or photon for the operation of superconducting tunneling junction as the detector. Using the electron beam evaporation technique under the high-vacuum pressure of 4 x 10^<-9>Pa, we fabricate epitaxial Nb and Ta layers on a sapphire substrate at the substrate temperature of 500 〜 700℃. Nb layer indicates the transition temperature (Tc) of 〜 9.3 K and the residual resistance ratio (RRR) of 〜 50. Ta layers indicates Tc 〜 4.5 K and RRR of 45 〜 140.
We have fabricated a Nb/AlOx-Al/Nb Josephson junction using magnetron-facing target sputtering technique. Nb and Al layers can be deposited under the high-density plasma in the condition that it is not directly exposed to the plasma region generated between a pair of targets. The transition temperature of the Nb layer and the residual resistance ratio have indicated 9.3 K and more than 3. The Nb/AlOx-Al/Nb Josephson junction has exhibited current-voltage characteristics with a low subgap leakage current.
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Research Products
(6 results)
