Synthetic antiferromagnetic (SAF) particles with perpendicular anisotropy display a number of desirable characteristics for applications in biological and other fluid environments.We present an efficient and effective method for the patteming of ultrathin Ruderman-KitteI-Kasuya-Yoshida coupled,perpendicularly magnetised SAFs using a combination of nanosphere lithography and ion milling.AGe sacrificial layer is utilised,which provides a clean and simple lift-off process,as well as maintaining the key magnetic properties that are beneficial to target applications.We demonstrate that the method is capable of producing a particularly high yield of well-defined,thin film based nanoparticles.