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A phased array based on large-area electronics that operates at gigahertz frequency


Large-aperture electromagnetic phased arrays can provide directionally controlled radiation signals for use in applications such as communications, imaging and power delivery. However, their deployment is challenging due to the lack of an electronic technology capable of spanning large physical dimensions. Furthermore, applications in areas such as aviation, the Internet of Things and healthcare require conformal devices that can operate on shaped surfaces. Large-area electronics technology could be used to create low-cost, large-scale, flexible electromagnetic phased arrays, but it employs low-temperature processing that limits device- and system-level performance at high frequencies. Here we show that inductor–capacitor oscillators operating at gigahertz frequencies can be created from large-area electronics based on high-speed, self-aligned zinc-oxide thin-film transistors. The oscillator circuits incorporate frequency locking and phase tuning, which are required for electromagnetic phased arrays. We integrate our phase-tunable oscillators in a 0.3-m-wide aperture, creating a phased array system that operates at ~1 GHz and is capable of beamforming.

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Fig. 1: Values of D/λ of LAE and device optimization.
Fig. 2: Architecture of the designed phased array system.
Fig. 3: Gigahertz LAE-based oscillator with phase tunability.
Fig. 4: Phase tuning based on injection locking.
Fig. 5: System demonstration.

Data availability

The data that support the plots within this paper and other findings of this study are available from the corresponding author upon reasonable request.


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This work was supported in part by Center for Brain-Inspired Computer (C-BRIC), one of the six centres in JUMP sponsored by DARPA, under grant number 40001859-075 (N.V., C.W., Y. Ma and P.K.), and by Princeton Program in Plasma Science and Technology (PPST) (J.C.S. and Y. Mehlman). This work also utilized the Princeton Institute for the Science and Technology of Materials (PRISM) cleanroom facilities. We thank S. Venkatesh from Princeton University for the helpful discussions.

Author information




N.V., J.C.S. and C.W. conceived the idea of the LAE-based phased array and experiments. N.V., J.C.S. and S.W. supervised the project. C.W. and Y. Mehlman designed, fabricated and performed the measurements of the LC oscillators. Y. Mehlman fabricated and characterized the devices. Y. Ma characterized the material. C.W. designed and prototyped the phased array circuits/systems, and performed the measurements together with Y. Mehlman, P.K., T.M. and H.J. C.W. wrote the manuscript with the help of N.V., S.W. and J.C.S. All the authors discussed the results and commented on the manuscript.

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Correspondence to Naveen Verma.

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The authors declare no competing interests.

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Peer review information Nature Electronics thanks George Kyriacou and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary Information

Supplementary Figs. 1–9 and Table 1.

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Wu, C., Mehlman, Y., Kumar, P. et al. A phased array based on large-area electronics that operates at gigahertz frequency. Nat Electron 4, 757–766 (2021).

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