JACOW

Research and Development of an Ultrahigh Precision Single Ion Implanter

Yosuke Yuri, Kouichi Hosaka, Nobumasa Miyawaki, Seiji Hosoya, Yasuyuki Ishii, H. Kashiwagi, Ryohei Yamagata, Kazumasa Narumi, Shinobu Onoda, Kento Muroo, K. Ito, H. Okamoto

Published Nov 28, 2025• 0 citations

Publisher

Abstract

Ion implantation is an accelerator technology essential for creating defects or introducing impurities into materials. A research and development study is currently underway at QST Takasaki Institute toward ultrahigh-precision single-ion implantation based on laser-cooling techniques. To achieve this, we incorporate a linear Paul trap as an ultracold single-ion source, where trapped ions can be cooled to the order of mK or even “Coulomb-crystallized” by Doppler laser cooling. In our scheme, N or Si ions, useful for ion implantation to create color centers, are sympathetically cooled down to the mK range through Coulomb collisions by co-trapping them with laser-cooled Ca ions. Then, the ions are extracted selectively from the trap to be accelerated and focused through a 50-kV electrostatic bipotential lens system. We aim to focus the ions on the order of 10 nm for ultrahigh-precision implantation. The implantation system has already been assembled, and the commissioning is currently underway to enable ion extraction using a Coulomb crystal and focusing extracted cold ions. We present the status of system development and outline the scheme for selective ion extraction and nanobeam focusing based on multiparticle simulations.

DOI: 10.18429/jacow-cool2025-mod2

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