Advancing Glass Engineering: Harnessing Focused Electron Beams for Direct Microstructuring.

A technological approach for direct glass structuring is presented by exploiting electron-beam-induced defect generation utilizing a conventional scanning electron microscope (SEM). The structuring process is assumed to be linked to electron-beam-induced ion migration and allows to create structures of several hundred nanometers in depth. It is demonstrated that the structuring can be realized in literally any SEM, which thus enables a comparatively simple implementation in support of a broad field of applications. The experiments are realized using electron energies of 5 to 15 keV in combination with different kinds of glasses, such as fused silica and ultra-low expansion glass, that are equipped with a charge dissipation top-layer. By controlling the beam trajectory at the surface and the electron beam parameters, freeform structuring, structure arrays, direct embedding of metal structures into the glass surface, and beam-defined three-level patterning are realized. The shown electron beam-based glass structuring extends therefore the current possibilities in a complementary manner, enabling further fabrication strategies and direct structuring even of fragile, 3D-structured surfaces.