View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by International Journal of Research and Engineering International Journal of Research and Engineering ISSN: 2348-7860 (O) | 2348-7852 (P) | Vol. 6 No. 3 | June 2019 | PP. 612-615 Digital Object Identifier DOI® http://dx.doi.org/10.21276/ijre.2019.6.3.2 Copyright © 2019 by authors and International Journal of Research and Engineering This work is licensed under the Creative Commons Attribution International License (CC BY). creativecommons.org/licenses/by/4.0 | | Resistive Random Access Memory (ReRAM) ORIGINAL ARTICLE Author(s): 1*Muthu Dayalan Affiliation(s): 1Senior Software Developer, ANNA University, Chennai, India *Corresponding author: [email protected] Abstract - Resistive Random-Access Memory ReRAM is comparable to the NAND Flash memory in that (ReRAM) technology has been viewed as one of the ReRAM operates through creating resistance instead of most reliable non-volatile memories that have are storing charge [2]. The materials of the ReRAM are built to emerging in markets. In this research paper, the change resistance when current is applied. Figure one below compares the NAND-based memory and a RRAM-based revolution of ReRAM will be analyzed. Also, the structure of a memory. paper will also review the recent progress in the technological development of ReRAM. The performance parameters of these non-volatile memories such as their operating voltage, operation speed, resistance ratio, endurance, retention time, device yield, and multilevel storage will be IJRE. This is an Open Access article under the CC BY 4.0 license. 4.0 BY the CC under article Access an is Open This IJRE. analyzed. Integration and reliability of Re-RAM in - The applications of ReRAM popularly known include the the practical level is compared with other types of memories for computers, consumer electronics, memories. Challenges faced by users of ReRAM smartphones, tablets, and enterprise storage. With the are addressed in regards to technological fallbacks technological advancements, it is expected that there will be among other challenges. Finally, the future more growth opportunities for the ReRAM application. In research on the ReRAM will be analyzed. the coming years, ReRAM will be used in automotive infotainment and navigation systems, deep learning, Keywords: resistive random access memory, resistive wearables, and the Internet of Things (IoT). switching, performance parameters, resistance switching, electrochemical devices. II. HISTORICAL PERSPECTIVES OF RE- RAM I. INTRODUCTION For more than four decades, the Flash Memory technology has dominated the electronic memory industry. However, it RRAM, also referred to as ReRAM (resistive random-access was until the early 2000s that ReRAM was developed with memory), is a form of nonvolatile storage that operates by some pioneer companies such as KB-capacity scale [3]. changing the resistance of a specially formulated solid Different forms of ReRAM have been developed whereby dielectric material [1]. The ReRAM device are known to manufacturers use different dielectric materials to gain a have a component, memristor, which contracts thus creating more effective storage device. Over the years, RAM some form of resistance which differs with voltages memory devices have been drastically been changed to imposed to it. ReRAM is an emerging technology that is improve speed and performance of GPUs, CPUs, and being applied by many users and has the special features of Computing processes thus have developed exponentially combining the advantages of both RAM and Flash. It is [3]. likely to replace the flash as it performs highly and has manufacturability benefits as compared to the competing III. CURRENT TRENDS OF RE-RAM replacement alternatives. Unlike other types of RAM Currently, the demand for high-driven memory devices has memories, ReRAM involves production of defects in a thin been promised through the revolution of flash cards and oxide layer, known as oxygen vacancies, that are RAM devices. The high-standards of next-generation subsequently charge and drift under an electric field. memory demands portray that there are limiting current Flash technology in terms of its crucial scaling limitations [4]. Also, the demand for storage devices that consume less Copyright © 2019 The Author(s). Published by International Journal of Research and Engineering Engineering and Research of Journal International by Published Author(s). The 2019 © Copyright IJRE | Vol. 6 No. 3 | June 2019 | M. Dayalan 613 energy, cheap, and with a high switching speed has retained research on how reliability and integration of ReRAM is to sustainability of the ReRAM market [5]. The overall market be effective. Development of techniques to understand the size for Flash memory is estimated to be approximately $40 failures of ReRAM is considered as part of integration. An billion which is growing a steady rate. However, with the example provided is on how a transmission electron emergence of the non-volatile memory market, it is microscope with an electron energy-loss spectroscopy expected that the market will increase from $ 580 million to function will be a powerful tool to investigate how the $ 3,527 million by 2020. According to predictive analytics, interface features between metal electrodes and the oxide the use of ReRAM is expected to grow remarkably from layer interact. Another integration portrayed is how the 2019 onwards since it was observed to be growing at CAGR capacitance of MOM structure certainly affects the fast of 53.07% from 2015 to 2020. ReRAM technology is operation of the ReRAM device [10]. currently considered to be compatible to the CMOS technologies. Being the best resistance switching carrier, the VI. RESISTANCE SWITCHING CONCEPT material approved for the manufacture of the ReRAM chips One of the fundamental characteristics of ReRAM is the are metal oxides in group VI and III-V semiconductors [6]. resistance switching physical effect. The resistance switching phenomenon having been under research for more IV. PERFORMANCE PARAMETERS OF than 40 years, engineers have for long been working in a RE-RAM memory that would have a strong resistance to the over The resistive RAM (ReRAM) is popular for its exemplary charged currency. In 2002, when the first ReRAM was performance in the memory-class devices. The devices have developed [11], the engineers responsible demonstrated that a fast access time, pertains an ultra-low stand-by power thus ReRAM would perfectly operate below 3V and 2 mA. making it cost effective. The device is highly reliable as it ReRAM has been considered as the best candidate for the makes it a viable technology that can perfectly replace the beyond-2Xnm generation of the nonvolatile memories [11]. DRAM technologies. The circuit operations parameters of One reason for this classification is its high compatibility ReRAM are considered essential in promoting its features with the CMOS technologies. remarkable performance. Some of the circuit operation VII. PROS AND CONS OF RE-RAM IJRE. This is an Open Access article under the CC BY 4.0 license. 4.0 BY the CC under article Access an is Open This IJRE. parameters include the pulse amplitude and pulse widths of - the word-line (WL) voltage, bit-line (BL) voltage, and There are several advantages and disadvantages that linked source-line (SL) voltage can be used to lower latency, lower to the use and features of ReRAM. To begin with the pros, power and thus improve reliability [8]. The appropriate the ReRAM are attributed to consume less power as choice of these types of voltages has been used to reduce compared to other RAM devices installed in computers [12]. latency of the 1T1R cell by 29.4% and minimize the write The Re-RAM has a simple structure which is small in size. energy by 46.7% over the DRAM cell. Re-RAMs are also fast both in performance and in the switching speed. The devices are also advantageous since Other performance parameters improving the operations of they have a high endurance and a high retention time aspect ReRAM include its operation voltage, high operation speed, thus can be scaled down to meet the nanometers measures as high resistance ratio, endurance strengths, high retention well as the 3D stacks that reduce the die area. In past time, device yield, and multilevel storage [7]. The numerous research studies on binary-based-based ReRAM, researchers resistive-switching mechanisms that portray the high acknowledge that ReRAM have stable resistance traits ReRAM capabilities include conductive filament, space- existing in the bipolar mode rather than the unipolar mode. charge-limited conduction, trap charging and discharging The low-power consumption of the ReRAM operation features. Schottky Emission, and Pool-Frenkel emission are makes the devices strong cost competitiveness to ReRAM. some of the proposed performance enhancements that will continuously improve the resistive switching features of VIII. CHALLENGES OF USING AND RRAM devices. DEVELOPING RE-RAM The new non-volatile memory technology is faced with V. INTEGRATION AND RELIABILITY several challenges. Firstly, the application of flash OF RE-RAM technology has long been embraced by most tech-users. As The potential of ReRAM devices has been observed through a result, the competition in the memory industry is relatively the practical application level. However, there are more high for the ReRAM users. Despite some of the ReRAMs, pressing issues presented for how the ReRAM operates. The such as the Crossbar’s ReRAM, has successfully replaced controlling abilities of the oxidation of the metal during the some of the flash memory devices [12]. thin film growth has made the device more reliable than other storage devices [9]. The oxide layer on the ReRAM More so, in the development of ReRAMs, developers of this electrode plates plays a crucial role in ReRAM resistance particular technology, face several challenges. One of the switching operations. Researchers advocate for more main challenges is on how to overcome temperature sensitivity during the manufacturing phase without Copyright © 2019 The Author(s).