Microfabrication of axicons by glass blowing at a wafer-level

This Letter reports on the generation of glass-based axicons realized at the wafer level by means of microfabrication. The technique is based on micro glass blowing allowing parallel fabrication of numerous components at a time. Blowing is achieved due to cavities containing a gas that expands when the wafer stack is introduced in a furnace. Such cavities, generated in a silicon wafer and sealed by a bonded glass wafer, act as pistons pushing locally the other side of the glass wafer where the micro-optical component profile emerges. After cavities' removal by polishing, it is shown that such a component produces nondiffracting Bessel beams.