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Semiconductor Physics, Quantum Electronics & Optoelectronics. 2006. V. 9, N 1. P. 022-028.
Diamond microcrystallites formation through
the phase transition graphite→liquid→diamond
Department of Environmental and Materials Science, Teikyo University of Science & Technology,
2525 Yatsusawa, Uenohara-machi, Kitatsuru-gun, Yamanashi-pref., 409-0193, Japan
E-mail: semikina@edd.ntu-kpi.kiev.ua
Abstract. The paper presents the results of synthesizing the diamond microparticles (3 to
5 µm) in a spark discharge in hydrogen at the low pressure (100 Torr). The obtained
growth rate ~5 µm/s is uniquely high. Our analysis of the nature of particles by using
SEM and Raman spectroscopy demonstrates that these particles are cubic high quality
diamond. Using the result of SIM images after cross-cutting of the sample by FIB, it is
concluded that diamond does not grow on the substrate and running process is not CVD.
Discussing the theory of the spark discharge, it is suggested that the process occurs at
high pressures and temperatures. A hypothesis of diamond formation through a diffusion
mechanism of the direct phase transition is presented.
Keywords: diamond microparticle, spark discharge, direct phase transition, threefold
point of the phase diagram.
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