High-throughput manufacturing of transparent fused silica glass by injection molding and extrusion

Due to high optical transparency combined with high thermal and chemical stability transparent fused silica glass is of high interest for many applications in microsystems engineering, especially in the field of microfluidics and micro optics. However, structuring of fused silica is inherently difficult and usually includes high temperatures, complicated and toxic etching processes or time consuming grinding protocols with severe limitation to freedom of design and manufacturing speed. Thus, complex structured fused silica glass has been limited especially on the industrial scale. We developed highly filled, thermoplastic fused silica nanocomposites (so-called Glassomers), that can be processed using commonly available high-throughput polymer manufacturing technologies such as injection molding or continuous extrusion. After the shaping process the thermoplastic Glassomer is converted to pure, transparent glass by subsequent debinding and sintering yielding high-quality fused silica glass with high optical transparency (transmission >90 %) and optical surface quality (R_q < 5 nm). We show injection molding of high-resolution microstructures as well as complex shaped macroscopic components that are subsequently converted to pure fused silica glass enabling for the first time mass-market manufacturing of fused silica glass components, enabling a plethora of applications in micro optics and lab-on-a-chip devices.