A new technique for enhancing sensitivity of 2ω method by applying bismuth film thermoreflectance sensor on a metal-dielectric sample
In this study a new technique for enhancing sensitivity of the 2ω method is discussed. In this technique a very thin bismuth film (<15 nm) is deposited on top of the sample, such as Au-Al2O3 sample, to enhance sensitivity of the 2ω method. Problem with the conventional 2ω method is that it is very hard to give good signal-noise-ratio of the ac-temperature measurement for a metal film, such as Au film, because it has very low thermoreflectance coefficient and electrical resistance. On the other hand, Bi film has very high thermoreflectance coefficient and electrical resistance. Therefore it seemed to be possible to measure the thermal resistance of Au-Al2O3 sample with good signal-noise-ratio, by applying Bi film on top of the Au-Al2O3 sample. We solved the thermal conduction equation of Bi-Au-Al2O3 thermal system and obtained the same approximate equation as that of Au-Al2O3 thermal system. By making measurement for Bi-Au-Al2O3 sample, we successfully determined the interfacial thermal resistance between Au film and Al2O3 substrate with much improved precision than that of the conventional 2ω method.
Thin film Interfacial thermal resistance Frequency-domain thermoreflectance Bismuth
Ryozo Kato Yibin Xu
National Institute for Materials Science Address: 1-2-1 Sengen, Tsukuba,Ibaraki, 305-0047 Japan National Institute for Materials Science Address: 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047 Japan
国际会议
The Ninth Asian Thermophysical Properties Conference(第九届亚洲热物理性能会议 ATPC 2010)
北京
英文
288-291
2010-10-19（万方平台首次上网日期，不代表论文的发表时间）