학술논문

Dual-Mode Operations of Self-Rectifying Ferroelectric Tunnel Junction Crosspoint Array for High-Density Integration of IoT Devices
Document Type
Periodical
Source
IEEE Journal of Solid-State Circuits IEEE J. Solid-State Circuits Solid-State Circuits, IEEE Journal of. 58(7):1860-1870 Jul, 2023
Subject
Components, Circuits, Devices and Systems
Engineered Materials, Dielectrics and Plasmas
Computing and Processing
Arrays
Internet of Things
Electrodes
Hysteresis
Tantalum
Optical switches
Junctions
Area efficiency
content addressable memory (CAM)
crosspoint array
dual-mode operation
Internet of Things (IoT)
leakage current
physically unclonable function (PUF)
self-rectifying ferroelectric tunnel junction (SR-FTJ)
Language
ISSN
0018-9200
1558-173X
Abstract
This study proposes a self-rectifying ferroelectric tunnel junction (SR-FTJ) crosspoint array to satisfy the stringent size requirements of the Internet-of-Things devices. Each cell in the SR-FTJ crosspoint array consists of two SR-FTJs stacked vertically, resulting in ultrahigh density. The SR-FTJ crosspoint array can operate as: 1) ternary content-addressable memory (TCAM) or 2) binary content addressable memory (BCAM) or physically unclonable function (PUF) in the dual-mode operation. In the dual-mode operation, the amount of the current flowing through the SR-FTJs remains the same, resulting in a stable PUF response regardless of the BCAM data. The dual-mode operation of the SR-FTJ crosspoint array is experimentally verified by 4-in wafer-level demonstrations. HSPICE simulation results using the industrial-compatible 180-nm technology with the SR-FTJ model reflecting measured characteristics show that the SR-FTJ crosspoint array achieves the lowest search energy (2.05 fJ/search/bit) and the highest randomness (Hamming weight of 0.5000) among the previous content addressable memories (CAMs) and PUFs. In addition, the SR-FTJ crosspoint array reduces area by $>$ 84.2% compared to the previous structures that implement individual CAM and PUF.