Application of gas field ion source and liquid metal alloy ion source based focused ion beams

I will present recent results obtained in our group using gas field ion sources (GFIS)1 and liquid metal alloy ion
source (LMAIS)2 based focused ion beams (FIB). I will briefly explain the source technology and our efforts
in developing new and unconventional ion sources for their application in FIB instruments. A few selected
examples will include the LMAIS based fabrication of single photon emitters (SPE) which are fundamental
building blocks for future quantum technology applications. I will present a method to fabricate at will placed
single or few SPEs emitting in the telecom O-band in Silicon3 . The successful integration of these telecom
quantum emitters into photonic structures such as micro-resonators, nanopillars and photonic crystals with
sub-micrometer precision paves the way toward a monolithic, all-silicon-based semiconductor-superconductor
quantum circuit for which this work lays the foundations. To achieve our goal we employ home built AuSi
and a unique CeC LMAIS both operated in an Orsay Physics CANION M31Z+ FIB. Silicon-on-insulator
substrates from different fabrication methods have been irradiated with a spot pattern. The achieved lateral
SPE placement accuracy is below 100 nm in both cases and the success rate of SPE formation is more than
50%. In addition I will present recent results obtained on the helium ion microscope using FIB and He ion
extracted from a GFIS source. These examples will include the epitaxial over growth of Sn spheres during He
ion beam irradiation. This more fundamental experiment show cases the importance of the ion beam driven
generation of interstitials and their diffusion during the ion beam irradiation4 . Finally, I’d like to demonstrate
how GFIS based HIM can be used to generate electrically controlled magnetic landscapes in spin orbit torque
(SOT) materials. Here, we use in-situ controlled irradiation to identify the best irradiation conditions for the
preparation of µm sized areas which will switch magnetization direction at different SOT currents5 .
Financial support by the COST Action CA19140 is acknowledged. http://www.fit4nano.eu/