Writing with Mass-Selected Ions Using a Dynamic Field Wien Filter

We have designed and constructed a low-cost Wien filter based on strong permanent magnets and integrated it into an ion soft-landing instrument to enable parallel deposition as well as one- and two-dimensional surface patterning of mass-selected ions using dynamic fields. We show the capabilities of this device for separating ions from a multicomponent high-flux continuous ion beam and simultaneous deposition of ions of different mass-to-charge ratios onto discrete locations on a surface. When a dynamic electric field is applied parallel to the magnetic field, ions are deposited in one-dimensional arrays, laterally separated by mass. The field's strength, frequency, and waveform type determine both the lengths of the arrays and the density of ions across the 1-D pattern. Additionally, a second dynamic field from user-defined waveforms orthogonal to the magnetic field enables two-dimensional surface patterning of ions while maintaining mass separation. These experiments demonstrate the practical utility of a Wien filter for the controlled fabrication of interfaces with arbitrary patterns of mass-selected ions.