[Show abstract][Hide abstract] ABSTRACT: We report the successful isotope separation and bulk single crystal growth of 29Si and 30Si stable isotopes. The isotopic enrichments of the 29Si and 30Si single crystals determined by mass spectrometry are 99.23% and 99.74%, respectively. Both crystals have the electrically active net-impurity concentration less than 1015 cm-3. Thanks to the result of this work and the 28Si crystals we grew previously, high quality single crystals of every stable Si isotope (28Si, 29Si, and 30Si) have been made available for a wide variety of basic research and industrial applications.
Japanese Journal of Applied Physics 10/2003; 42(10):6248-6251. DOI:10.1143/JJAP.42.6248 · 1.13 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.
[Show abstract][Hide abstract] ABSTRACT: The results of the first preparation of highly enriched, high-pure 28Si single crystals without dislocations and high crystal-perfection is presented. The high-pure silicon tetrafluoride gas has been used as the starting material for isotope separation and enrichment by means of centrifugation method. On its base polycrystalline 28Si was obtained. No isotopic dilution has been observed at all stages of conversion of silicon from tetrafluoride to crystal. Two charges with various 28Si content, but approximately of the same purity, were prepared.
Crystal Research and Technology 09/2000; 35(9):1023 - 1026. DOI:10.1002/1521-4079(200009)35:9<1023::AID-CRAT1023>3.0.CO;2-V · 0.94 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: By means of a steady-state heat-flow technique, we have measured the thermal conductivity in a bulk crystal of highly enriched (99.8588%) 28Si for temperatures between 2 and 310 K. Maximum values of about 30 000 W m−1 K−1 for κ are found around 20 K. This is six times larger than in natural silicon and even exceeds the maximum in diamond with natural isotope abundance. At room temperature, we obtain a thermal conductivity enhancement of almost 60% compared to natural Si. Our results agree well with theoretical predictions.