Realization of Minimum and Maximum Gate Function in Ta2O5-based Memristive Devices.

Thomas Breuer,Lutz Nielen,Rainer Waser,Eike Linn,Bernd Roesgen,Vikas Rana

doi:10.1038/srep23967

Abstract

Redox-based resistive switching devices (ReRAM) are considered key enablers for future non-volatile memory and logic applications. Functionally enhanced ReRAM devices could enable new hardware concepts, e.g. logic-in-memory or neuromorphic applications. In this work, we demonstrate the implementation of ReRAM-based fuzzy logic gates using Ta2O5 devices to enable analogous Minimum and Maximum operations. The realized gates consist of two anti-serially connected ReRAM cells offering two inputs and one output. The cells offer an endurance up to 106 cycles. By means of exemplary input signals, each gate functionality is verified and signal constraints are highlighted. This realization could improve the efficiency of analogous processing tasks such as sorting networks in the future.

Highlights

Resistive switching memories (ReRAM) are considered as highly attractive emerging technology to implement future high-density non-volatile memory or storage[1,2,3,4]
A two-input-one-output ReRAM structure is used for routing[16], structural identical to the complementary resistive switch structure with accessible middle electrode which we use for implementation of MIN/MAX gates (Fig. 1)
Each cell can toggle between a high resistive state (HRS) and a low resistive state (LRS)

Summary

Introduction

Resistive switching memories (ReRAM) are considered as highly attractive emerging technology to implement future high-density non-volatile memory or storage[1,2,3,4]. The proposed gate structure consists of two anti-serially connected devices, i.e. the device stack is very similar to a conventional complementary resistive switch, but offers a third terminal at the middle electrode[16,27,28]. Being aware of those constraints, which will be discussed in detail, ReRAMs are well suited for the implementation of memristive fuzzy logic gates The feasibility of both Minimum and Maximum function is experimentally demonstrated in this paper by using integrated CRS devices, which offer an access to the middle electrode. By applying a negative voltage, the CRS devices switches to the transition state LRS/LRS, since the TC sets at Vth,[3]. The crucial points for the implementation of Minimum (MIN) and Maximum (MAX) logic are:

Methods

Results

Discussion

Conclusion