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edfas.org ELECTRONIC DEV ICE FA I LURE ANALYSIS | VOLUME 23 NO . 4 36 dissipation, and temperature. Finding a scaling relation- ship is complicated and predicting the voltage breakdown limit is difficult. In some cases, a DC voltagemeasurement can be a good indicator of the RF breakdown, [10] however this test is not consistent as aparametric screeningandcan result in breaking the device. Ways to better predict the RF breakdown of a device before installing it into a chamber and thereby anticipate the safe, high running voltage of the device thatmeets the trap experimental requirements are underway. In attempting to reduce the likelihood of RF breakdown it is most straightforward to increase the top IMD thickness and the lateral (horizontal) gaps around the RF electrodes, however there are limits to these increases making this a challenging problem to solve. OUTLOOK The fabrication and application of quantum devices for NISQ computing is an exciting and dynamic field. The quality and reliability of quantum devices is beginning to mature past fabrication of one-of-a-kind research devices, cherry picked for use inQIS experiments, toward theman- ufacturing of defect-free, high yield devices for applica- tions capable of executing complex quantumalgorithms. As with classical electronic devices, identifying and elimi- nating failuremodes in quantumdevices will be essential to realize quantum systems at a meaningful scale. This will be true regardless of the qubit modality, be it trapped ion qubits, solid state qubits, or superconducting qubits. While only a few of the failure modes encountered so far with ion trap devices have been discussed here, there will undoubtedly be new reliability problems uncovered as device use times are extended. Likewise, other qubit technology efforts are working hard on understanding failure modes specific to their devices, as well as tuning qubits, and improving fabrication yields anddevice design tolerances. [18] Interestingly, the approaches and the tools used to perform failure analysis of qubit technologies may likely depend on the qubit modality. A unique difference in ion qubits when compared with superconducting and solid- state qubits is that the ion trap device only defines the electric fields that form the trapping well for the ion – the ion itself being the qubit. So, imperfections in trap device fabrication and operation can cause electric field noise in the trapping fields, but they do not fundamentally affect the nature of the ion qubit. For superconducting and solid-state qubits, on the other hand, the devicematerials, processing, and dimensional tolerances define the nature and behavior of the qubit itself (in fact these qubit types are often referred to as artificial atoms). Hence, failure mode analysis techniques for these devices will likely be quite different from an ion trap device. No matter the nature of the qubit, however, coherent operations on the qubit will be the first, and sometimes best, failure analysis technique. Acknowledgments Thismaterialwas funded inpartby theU.S. Department of Energy, Office of Science, Office of Advanced Scientific Computing Research Quantum Testbed Program. It was also supported in part by the Office of the Director of National Intelligence (ODNI), Intelligence Advanced Research Projects Activity (IARPA) under the Logical Qubits (LogiQ) program. The authors also thank the ion trap device technology and experimental science team members at Sandia, in particular Eric Ou and Joshua Wilson, as well as the external collaborators who have contributed to ion trap development over the years. Sandia National Laboratories is a multimission labo- ratory managed and operated by National Technology & Engineering Solutions of Sandia, LLC, a wholly owned subsidiary of Honeywell International Inc., for the U.S. Department of Energy’s National Nuclear Security Ad- ministration under contract DE-NA0003525. This paper describes objective technical results and analysis. Any subjective views or opinions that might be expressed in thepaper donot necessarily represent the views of theU.S. Department of Energy or the United States Government. References 1. J. Stolze and D. Suter: Quantum Computing: A Short Course from Theory to Experiment, WILEY-VCH GmbH & Co. KGaA, Weinheim, 2004. 2. S. Clark, et al.: “Engineering the Quantum Scientific Computing Open User Testbed (QSCOUT): Design details and user guide,” arXiv:2104.00759v1 [quant-ph], 2021. 3. J.M. Pino, et al.: “Demonstration of the Trapped-ion Quantum CCD Computer Architecture,” Nature, 2021, 592, p. 209–213. 4. Y. 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Blain, et al.: “Hybrid MEMS- CMOS Ion Traps for NISQ Compu- ting,” Quantum Science and Technology, 2021, 6 (3), p. 034011. 11. C.R. Clark, et al.: “Characterization of Fluorescence CollectionOptics Integrated with a Microfabricated Surface Electrode Ion Trap,” Phys.