http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
- 中文 을 입력하시려면 zhongwen을 입력하시고 space를누르시면됩니다.
- 北京 을 입력하시려면 beijing을 입력하시고 space를 누르시면 됩니다.
RISS 인기검색어
- 검색키워드
- 저자 : 김용함(Yong-Hamb KIM) (검색결과 4 건)
- 무료
- 기관 내 무료
- 유료
-
-
이영화,김용함,Lee, Young-Hwa,Kim, Yong-Hamb 한국초전도학회 2008 Progress in superconductivity Vol.9 No.2
We are developing a sensitive gamma ray spectrometer based on superconducting transition edge sensors. The detector consists of a small piece of high purity Sn as an absorber and a Ti/Au bilayer as a temperature sensor. It is designed to measure the thermal signal caused by absorption of gamma rays. The mechanical support and the thermal contact between the absorber and the thermometer were made with Stycast epoxy. The bilayer was formed by e-beam evaporation and patterned by wet etching on top of a $SiN_X$ membrane. A sharp superconducting transition of the film was measured near 100 mK. When the film was biased to the edge of the transition, signals were observed due to single photon absorption emitted from an $^{241}Am$ source. The measured spectrum showed several characteristic peaks of the source including 59.5 keV gamma line. The full with at half maximum was about 900 eV for the 59.5 keV gamma line. The background was low enough to resolve low energy lines. Considerations to improve the energy resolution of the gamma ray spectrometer are also discussed.
-
이영화,김용함,Lee, Young-Hwa,Kim, Yong-Hamb 한국전기전자재료학회 2008 전기전자재료학회논문지 Vol.21 No.10
We report on the development of transition edge sensors for x-ray detection. The sensor technology was based on the fabrication of a superconducting film on a thin membrane. A bilayer of a superconductor, Ti, and a noble metal, Au, was e-beam evaporated on a micromachined SiNx. Another Au layer was evaporated on the two side edges of the bilayer in order not to be affected by structural imperfections at the boundaries. With the method described in the present report, the superconducting transition temperature of the device was consistently achieved to near 80 mK with a sharp transition. The energy spectrum ueasured with the device provided 37 eV FWHM for 5.9 x-rays. We also discuss the design and fabrication considerations as well as the performance of the device in detail.
-
김일환,이민규,김용함,Kim, Il-Hwan,Lee, Min-Kyu,Kim, Yong-Hamb 한국초전도학회 2010 Progress in superconductivity Vol.12 No.1
Low temperature micro-calorimeters have been employed in the field of high resolution alpha spectrometers. These alpha detectors typically consist of a superconducting or metal absorber and a temperature sensor. The temperature sensor can be a transition edge sensor (TES), a metallic magnetic calorimeter (MMC) or other low temperature detectors for an accurate measurement of temperature change due to an alpha particle absorption. We report a recent study of the heat flow between a replaceable absorber and a temperature sensor. A piece of gold foil in $2.4{\times}2.7{\times}0.03\;mm^3$ is used as an absorber. A $40\;{\mu}m$ diameter Au:Er paramagnetic sensor is attached to another small piece of gold foil in $400{\times}200{\times}30\;{\mu}m^3$ to serve as the temperature sensor. This sensor assembly, Au:Er and gold foil, is placed on a miniature SQUID susceptometer in a gradiometric configuration. The thermal connection between the absorber and the sensor was made with three gold bonding wires. The measured thermal conductance shows a linear dependence to the temperature. The values are in a good agreement with Wiedemann-Franz type thermal conductance of the gold wires.
연관 검색어 추천
이 검색어로 많이 본 자료
활용도 높은 자료
