TSV-integrated surface electrode ion trap for scalable quantum information processing
P. Zhao, J. P. Likforman, H. Y. Li, J. Tao, T. Henner, Y. D. Lim, W. W. Seit, C. S. Tan, L. Guidoni
Abstract
In this study, we report about the design, fabrication, and operation of a Cu-filled through-silicon via (TSV)-integrated ion trap. TSVs are placed directly underneath electrodes as vertical interconnections between an ion trap and a glass interposer, facilitating the arbitrary geometry design with increasing electrode numbers and evolving complexity. The integration of TSVs reduces the form factor of the ion trap by more than 80%, minimizing parasitic capacitance from 32 ± 2 to 3 ± 0.2 pF. A low RF dissipation is achieved in spite of the absence of the ground screening layer. The entire fabrication process is on a 12-in. wafer and compatible with the established CMOS back end process. We demonstrate the basic functionality of the trap by loading and laser-cooling single 88Sr+ ions. It is found that both the heating rate (17 quanta/ms for an axial frequency of 300 kHz) and lifetime (∼30 min) are comparable with traps of similar dimensions. This work pioneers the development of TSV-integrated ion traps, enriching the toolbox for scalable quantum computing.