Particle Fabrication Sequence.

Abstract

<p>Spin-coating of PMGI and PMMA on a clean silicon wafer (a) is followed by exposure of the sample to a broad beam of helium ions through a stencil mask to form the pattern (b). During development, the exposed areas of PMMA wash away, and a subsequent etch in TMAH removes the PMGI layer underneath the PMMA openings (c). The particles of interest are evaporated as stacked layers of 10 nm gold, 10 nm of permalloy, and 10 nm gold (d). A lift-off procedure removes the evaporated metal on top of the PMMA layer (e) and the PMGI layer is etched in TMAH solution (f) to release the particles.</p