Budget Amount *help |
¥13,200,000 (Direct Cost: ¥13,200,000)
Fiscal Year 2002: ¥2,900,000 (Direct Cost: ¥2,900,000)
Fiscal Year 2001: ¥10,300,000 (Direct Cost: ¥10,300,000)
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Research Abstract |
We report on the measurements of the thermal conductivity of natural (^<nat>Si) and isotopically pure ^<28>Si as a function of temperature. The isotopically enrichied ^<28>Si employed is dislocation free with the electrically active net-impurity concentration (p-type) less than 1x10^<15>cm^<-3>. Oxygen and carbon concentrations are less than 1x10^<17>cm^<-3> for it was under the detection limit of FTIR. At room temperature, the ^<28>Si sample is measured to have the thermal conductivity about 10% higher than that of ^<nat>Si. This increase is in agreement with the experimental result reported recently [A. V. Gusev, A. M. Gibin, O. N. Morozkin, V. A. Gavva, and A. V. Mitin, Inorganic Materials, 38, 1305 (2002)], but in sever disagreement with the previously reported value of 60% at the room temperature. [T. Ruf, R. W. Henn, M. Asen-Palmer, E. Gmelin, M. Cardona, H. -J. Pohl, G. G. Devyatych and P. G. Sennikov, Solid State Commun. 115, 243 (2000).] It is therefore important to identify the true thermal conductivity of ^<28>Si in the future.
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