Implementation of MeV heavy-ion implantation into a microstructures with a defined pattern structure using a nuclear microprobe

• Proton beam writing is used as an auxiliary method for patterned heavy-ion implantation. • Polymethylmethacrylate (PMMA) is suitable as a mask material for ion implantation, although it has some limitation. • MeV gold ions were implanted into glass in a pattern with mm-scale lateral resolution. Facilities equipped with electrostatic accelerators for ion beam analysis often perform high-energy ion beam implantation to dope target materials. A typical task of ion implantation is the uniform placement of ions over a large area using a wide-profile raster-scanned beam. Implantation of ions in a specific pattern (ion beam lithography) is also possible; however, this requires the use of masks, which are typically outsourced for production. Laboratories equipped with a nuclear microprobe can accomplish ion beam lithography without the need for masks, using the direct-write method, although the ion mass and energy may be limited by the magnetic rigidity of the microprobe focusing system. The aim of this work is to demonstrate the possibility of heavy ion lithography without the need for outsourced masks, using a nuclear microprobe as an auxiliary technique. The validity of the proposed method was established by implantation of 2.5 MeV gold ions into glass in a pattern with a minimum feature size of 3 μm. The potential challenges of this method are described in detail. The most critical issue of this method is material incompatibility.