3D printer based on two-photon polymerization technology for maskless microfabrication

• Subject Area: Electrical Engineering and Information Technology
• Term: Funded in 2024
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 538872077

This proposal deals with the procurement of a 3D printer system based on two-photon polymerization (“3D printer”) for the fabrication of complex 2.5D and 3D microstructures with state-of-the-art resolution and accuracy. Currently, the integration of novel quantum systems of the first and second generations is often limited by the constraints of conventional manufacturing techniques. Such quantum systems often require hybrid electro-photonic interfaces and interconnects, which are either impractical or impossible to achieve with traditional microfabrication techniques. This is true both for one-of-a-kind research systems and volume production. The 3D printer will be used to compactly integrate the required control structures for both spin-based and atom-based qubits, requiring the precise generation of high-frequency magnetic and electric fields, respectively. Applications of such quantum systems, especially in the field of biomedical sensing, additionally often require the precise handling and control of liquids through microfluidic structures, which have to be incorporated with the quantum device. The resulting structures are also very hard and/or time-consuming to fabricate using traditional planar, clean-room-based manufacturing methods. To enable the fabrication of the abovementioned structures, the requested system has to allow for the 3D fabrication of microstructures with (sub-)micrometer resolution and accuracy on a wafer scale, including the possibility of direct printing of micro-optical elements, such as lenses, diffraction gratings, and fiber-optic couplers. In order to allow for potential manufacturing scalability, automatic alignment of the 3D print to existing optical elements, such as fibers and photonic chips is required. Overall, this allows for a level of integration of complex hybrid photonic-electronic nano/micro systems with capabilities greatly extending the current state-of-the-art. Since the 3D printer itself can only print non-conducting polymers, we will use several different methods, including shadow masks for electrode evaporation and 3D printing, to produce the required conductive structures for the generation of the RF magnetic and electric fields for qubit control. Moreover, we can use the high precision of the 3D printer to print support structures with variable diameters, thin walls, and high aspect ratios to manufacture 3D coil structures using the 3D wire bonding process with insulated bond wires established in our lab. Such 2.5D and 3D geometries have significantly better field homogeneities than pure planar geometries, which are required for most modern quantum sensing and computing applications. In summary, the requested 3D printer will enable the development of novel concepts for hybrid integration of first and second-generation quantum devices and other smart sensors.

• DFG Programme: Major Research Instrumentation
• Major Instrumentation: 3D-Drucker basierend auf der Zwei-Photonen- Polymerisation für maskenlose Mikrofabrikation (Teilfinanzierung)
• Instrumentation Group: 2110 Formen-, Modellherstellung und gießereitechnische Maschinen
• Applicant Institution: Universität Stuttgart
• Leader: Professor Dr. Jens Anders