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Hardware-intrinsic security primitives enabled by analogue state and nonlinear conductance variations in integrated memristors


Hardware-intrinsic security primitives employ instance-specific and process-induced variations in electronic hardware as a source of cryptographic data. Among various emerging technologies, memristors offer unique opportunities in such security applications due to their underlying stochastic operation. Here we show that the analogue tuning and nonlinear conductance variations of memristors can be used to build a basic building block for implementing physically unclonable functions that are resilient, dense, fast and energy-efficient. Using two vertically integrated 10 × 10 metal-oxide memristive crossbar circuits, we experimentally demonstrate a security primitive that offers a near ideal 50% average uniformity and diffuseness, as well as a minimum bit error rate of around 1.5 ± 1%. Readjustment of the conductances of the devices allows nearly unique security instances to be implemented with the same crossbar circuit.

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Fig. 1: 3D ReRAM crossbar array.
Fig. 2: Memristor-based basic building block for cryptographic hardware.
Fig. 3: Experimental results for tuning and security performance.
Fig. 4: Experimental results for PUF UQ.

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This work was supported by AFOSR under MURI grant FA9550-12-1-0038, ARC DP140103448 and NSF grant CCF-1528502. The authors thank A. Chen and J. Rajendran for useful discussions.

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Authors and Affiliations



H.N., O.K. and D.B.S. conceived the original concept and initiated the work. G.C.A and B.H. fabricated devices. H.N., M.P. and F.M.B. developed the characterization set-up and performed measurements. H.N., J.K. and M.R.M. performed simulations and estimated performance. H.N. and D.B.S. wrote the manuscript. All authors discussed the results.

Corresponding authors

Correspondence to Hussein Nili, Omid Kavehei or Dmitri B. Strukov.

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The authors declare no competing interests.

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Supplementary Sections 1–10, Supplementary Figures 1–9 and Supplementary Tables 1–3

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Nili, H., Adam, G.C., Hoskins, B. et al. Hardware-intrinsic security primitives enabled by analogue state and nonlinear conductance variations in integrated memristors. Nat Electron 1, 197–202 (2018).

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