High-performance bilayer flexible resistive random access memory based on low-temperature thermal atomic layer deposition.

Run-Chen Fang,Peng-Fei Wang,Peng Zhou,Wen Yang,Qing-Qing Sun,David Wei Zhang

doi:10.1186/1556-276x-8-92

Abstract

We demonstrated a flexible resistive random access memory device through a low-temperature atomic layer deposition process. The device is composed of an HfO2/Al2O3-based functional stack on an indium tin oxide-coated polyethylene terephthalate substrate. After the initial reset operation, the device exhibits a typical bipolar, reliable, and reproducible resistive switching behavior. After a 104-s retention time, the memory window of the device is still in accordance with excellent thermal stability, and a 10-year usage is still possible with the resistance ratio larger than 10 at room temperature and at 85°C. In addition, the operation speed of the device was estimated to be 500 ns for the reset operation and 800 ns for the set operation, which is fast enough for the usage of the memories in flexible circuits. Considering the excellent performance of the device fabricated by low-temperature atomic layer deposition, the process may promote the potential applications of oxide-based resistive random access memory in flexible integrated circuits.

Highlights

Since flexible electronic system (FES) appeals to be light, convenient, has conformal contingence with the crooked surface, and excellent interfaces with humans, it ought to be a prospective existing form of electronic product to substitute its clumsy predecessors manufactured and packaged by traditional bulk silicon technology [1,2]
Flexible resistive random access memory (RRAM) was fabricated on polyethylene terephthalate (PET) substrate coated by indium tin oxide (ITO) conducting film, and ITO serves as the bottom electrode in our devices
trimethyl aluminum (TMA) was pulsed at room temperature, and tetrakis (ethylmethylamino)hafnium (TEMAH) was heated to 85°C to offer enough evaporation pressure

Summary

Introduction

Since flexible electronic system (FES) appeals to be light, convenient, has conformal contingence with the crooked surface, and excellent interfaces with humans, it ought to be a prospective existing form of electronic product to substitute its clumsy predecessors manufactured and packaged by traditional bulk silicon technology [1,2]. Atomic layer deposition (ALD) has emerged as a new technique for depositing films, for fabricating oxide films. Owing to its selflimiting mechanism during the process, excellent step coverage and conformal thickness of the film can be achieved [21]. The deposition of oxide film by ALD on bulk silicon is very mature, seldom had researchers used this method to deposit films on flexible substrate. The main reason is that the flexible substrate could not undergo high-temperature processing above 200°C, except in some cases such as depositing films using plasma-enhanced atomic layer deposition under low temperature where plasma damage and degradation of the step coverage is unavoidable [22]

Methods

Results

Conclusion