Single-Ion Counting with an Ultra-Thin-Membrane Silicon Carbide Sensor

Materials (Basel). 2023 Dec 18;16(24):7692. doi: 10.3390/ma16247692.

Abstract

In recent times, ion implantation has received increasing interest for novel applications related to deterministic material doping on the nanoscale, primarily for the fabrication of solid-state quantum devices. For such applications, precise information concerning the number of implanted ions and their final position within the implanted sample is crucial. In this work, we present an innovative method for the detection of single ions of MeV energy by using a sub-micrometer ultra-thin silicon carbide sensor operated as an in-beam counter of transmitted ions. The SiC sensor signals, when compared to a Passivated Implanted Planar Silicon detector signal, exhibited a 96.5% ion-detection confidence, demonstrating that the membrane sensors can be utilized for high-fidelity ion counting. Furthermore, we assessed the angular straggling of transmitted ions due to the interaction with the SiC sensor, employing the scanning knife-edge method of a focused ion microbeam. The lateral dimension of the ion beam with and without the membrane sensor was compared to the SRIM calculations. The results were used to discuss the potential of such experimental geometry in deterministic ion-implantation schemes as well as other applications.

Keywords: counting efficiency; deterministic ion implantation; membrane sensor; silicon carbide; spatial resolution.

Grants and funding

This project received funding from the European Union’s Horizon Europe Research and Innovation program under grant agreement No. 101057511 (EURO-LABS). This project was partially funded by the SAMOTHRACE project (Avviso 3277-“SAMOTHRACE” ECS00000022) and partially funded by the RADIATE project (European Union’s Horizon 2020 Research and Innovation program under grant agreement No. 824096).