  Focused ion beam (FIB) techniques are employed widely for nanofabrication,
and processing of materials and devices. However, ion irradiation often gives
rise to severe damage due to atomic displacements that cause defect formation,
migration and clustering within the ion-solid interaction volume. The resulting
restructuring degrades the functionality of materials, and limits the utility
FIB ablation and nanofabrication techniques. Here we show that such
restructuring can be inhibited by performing FIB irradiation in a hydrogen
plasma environment via chemical pathways that modify defect binding energies
and transport kinetics, as well as material ablation rates. The method is
minimally-invasive and has the potential to greatly expand the utility of FIB
nanofabrication techniques in processing of functional materials and devices.
