A practical guide for microdevice fabrication using a focused ion beam with a flip-stage

Electrical and thermal transport measurements are essential for investigating the electronic properties of single crystal materials. While traditional methods use manual contact placement on millimeter-scale crystals, they face severe limitations in resolution and reproducibility when dealing with crystals smaller than one millimeter. Focused ion beam lithography has emerged as a powerful alternative, enabling the fabrication of mesoscale devices with nanometer-scale precision, control over geometry and crystallographic orientation, deposition of electrical contacts and fabrication of minimally invasive probes—key features for ensuring accurate and reproducible measurements. The operating principle relies on a highly focused beam of ions that impacts the sample to locally sputter material. Being a kinetic technique, it can be applied to many chemically different compounds, enabling the characterization of newly discovered materials without requiring large crystallites or thin film growth. This work serves as a technical guide, introducing the use of an in-situ flip-stage for sculpting complex three-dimensional structures. We demonstrate our fabrication protocol using various single crystal, highlighting how the freedom to define 3D geometries enables the creation of unconventional device shapes, supporting more incisive material characterization and device prototyping.