28 nm HKMG-Based Current Limited FeFET Crossbar-Array for Inference Application
Sourav De, Franz Müller, Sunanda Thunder, Sukhrob Abdulazhanov, Nellie Laleni, Maximilian Lederer, Tarek Ali, Yannick Raffel, Stefan Dünkel, Shaown Mojumder, Alptekin Vardar, Sven Beyer, Konrad Seidel, Thomas Kämpfe
Abstract
This article reports a novel ferroelectric field-effect transistor (FeFET)-based crossbar array cascaded with an external resistor. The external resistor is shunted with the column of the FeFET array, as a current limiter and reduces the impact of variations in drain current ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">${I}_{d}$ </tex-math></inline-formula> ), especially in a low threshold voltage (LVT) state. We have designed crossbar arrays of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$8\times8$ </tex-math></inline-formula> sizes and performed multiply-and-accumulate (MAC) operations. Furthermore, we have evaluated the performance of the current limited FeFET crossbar array in system-level applications. Finally, the system-level performance evaluation was done by neuromorphic simulation of the resistor-shunted FeFET crossbar array. The crossbar array achieved software-comparable inference accuracy (~97%) for National Institute of Standards and Technology (MNIST) datasets with multilayer perceptron (MLP) neural network, whereas the crossbar arrays built solely with FeFETs failed to learn, yielding only 9.8% accuracy.