EDN: RKCCQW
Authors & Affiliations
Babaeva Yu.A., Stuk A.A., Kochnov O.Yu.
Karpov Research and Development Institute for Physical Chemistry, Obninsk, Russia
Babaeva Yu.A. – Lead Engineer. Contacts: 223, Lenin Ave., Obninsk, Kaluga Region, Russia. Tel.: +7 (919) 034-98-18; e-mail: This email address is being protected from spambots. You need JavaScript enabled to view it., This email address is being protected from spambots. You need JavaScript enabled to view it..
Stuk A.A. – Head of Department, Cand. Sci. (Tech.).
Kochnov O.Yu. – Doctor of Technical Sciences, Chief Engineer, Dr. Sci. (Tech.).
Abstract
The article presents a comprehensive analysis of the current state and development prospects of neutron transmutation doping (NTD) technology for silicon – a key method for producing high-quality semiconductor materials for power electronics and other advanced applications. The physical and chemical foundations of the method, based on the nuclear reaction converting silicon-30 isotope into phosphorus under the influence of thermal neutrons, are discussed in detail. It is shown that unique uniformity of dopant distribution is achieved due to the purity of initial single crystals grown by the float-zone method, isotropy of the target, transparency of the material to neutrons, and uniform irradiation. The problems of radiation defect formation and optimization of post-irradiation annealing for achieving ultimate electrophysical parameters (radial non-uniformity ≤ 2–3 %, deviation from nominal value ≤ 5–7 %, minority carrier lifetime ≥ 300 µs) are analyzed. Technological schemes of irradiation used in various types of reactors are presented, and the long-term operational experience of the “Topaz-2” installation at the VVR-ts reactor at JSC “Karpov Research and Development Institute for Physical Chemistry” (Obninsk) is described, where more than 50 tons of neutron-doped silicon (NDS) have been processed. Data on modern requirements of domestic consumers for the electrophysical parameters of NDS are provided, and the necessity for updating technical specifications is justified. Based on the analysis of foreign irradiation centers and global market dynamics (projected growth from 150 to 500 tons per year), the main development trends in silicon NTD are formulated: mastering diameters up to 200 mm, expanding the range of specific electrical resistance grades (from 6 Ω·cm to 500–600 Ω·cm), doping silicon grown by the Czochralski method, and producing detector-grade silicon and silicon for photodetectors. It is shown that Russia has established NDS production capacities up to 15 tons per year and has reserves for increasing production to 30 tons per year.
Keywords
neutron transmutation doping, neutron-doped silicon (NDS), float-zone melting, power electronics, radiation defects, (n,γ) nuclear reaction, annealing, research reactor, specific electrical resistivity, minority carrier lifetime, global trends
Article Text (PDF, in Russian)
References
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UDC 621.315.592
Problems of Atomic Science and Technology. Series: Nuclear and Reactor Constants, 2026, no. 2, 2:14
