On-chip stencil lithography for superconducting qubits

These folders contain the main raw data presented in the following paper: "On-chip stencil lithography for superconducting qubits - Roudy Hanna et al. " ------------------------------ Improvements in circuit design and more recently in materials and surface cleaning have contributed to a rapid development of coherent superconducting qubits. However, organic resists commonly used for shadow evaporation of Josephson junctions (JJs) pose limitations due to residual contamination, poor thermal stability and compatibility under typical surface-cleaning conditions. To provide an alternative, we developed an inorganic SiO2/Si3N4 on-chip stencil lithography mask for JJ fabrication. The stencil mask is resilient to aggressive cleaning agents and it withstands high temperatures up to 1200°C, thereby opening new avenues for JJ material exploration and interface optimization. To validate the concept, we performed shadow evaporation of Al-based transmon qubits followed by stencil mask lift-off using vapor hydrofluoric acid, which selectively etches SiO2. We demonstrate average T1 ≈ 75±11 µs over a 200 MHz frequency range in multiple cool-downs for one device, and T1 ≈ 44±8 µs for a second device. These results confirm the compatibility of stencil lithography with state-of-the-art superconducting quantum devices and motivate further investigations into materials engineering, film deposition and surface cleaning techniques. ------------------------------ AFM_data: provides the raw data for the AFM scans presented in the appendix. Requires Gwyddion software. EDX_data: corresponding EDX scans of the two AFM scans before. Qubit_data: contains a Jupyter notebook which reads and plots all the data in the corresponding folder (a relative path can be added in the beginning of the notebook). This dataset provides all measurements presented in the paper, their analysis fit, and other relevant data that helped characterising them. Non-relevant data is not uploaded. Simulataion_data: shows the simulation data for creating the transmon qubit design.