The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The review provides a survey of non-volatile, highly scalable memory devices which are based on electrochemical and thermochemical phenomena controlling the resistance of nanoscale memory cells. The classification of the memory effects, the understanding of the underlying mechanisms, and a sketch of the integration efforts will be presented.
Highly reliable TaOx ReRAM has been successfully demonstrated. The memory cell shows stable pulse switching with endurance over 109 cycles, sufficient retention exceeding 10 years at 85degC. TaOx exhibits stable high and low resistance states based on the redox reaction mechanism, confirmed by HX-PES directly for the first time. An 8 kbit 1T1R memory array with a good operating window has been fabricated...
We propose carbon as new resistive memory material for non-volatile memories and compare three allotropes of carbon, namely carbon nanotubes, graphene-like conductive carbon and insulating carbon for their possible application as resistance-change material in high density non-volatile memories. Repetitive high-speed switching and the potential for multi-level programming have been successfully demonstrated.
We present the fabrication method and the electrical performance of nanoscale crosspoint junctions for two different metal/ oxide/ metal configurations. 100 ?? 100 nm2 small cells were fabricated by e-beam lithography and nanoimprint lithography (NIL), respectively. The electrical results show switching speeds of less than 10 ns for the SET and RESET operations, and resistance changes of several orders...
Results of detailed experimental study of recovery times of threshold voltage, low field resistance, threshold current and maximum delay are reported with different film thickness. It was shown that the shortest recovery time has low field resistance. Threshold voltage and current recovery proceed slower. The threshold current recovery curve for OTS alloy demonstrates minima and saturates synchronously...
The resistive switching behavior of Ag/Si3N4/Pt device was observed and studied for the first time. Resistance ratio larger than 4*102 and 104s retention time were achieved which indicating its potential for resistive switching memory application. A physical model is proposed to explain the resistive switching behaviors of Ag/Si3N4/Pt devices.
The resistance switching characteristics of several metal oxides has been reported recently for nonvolatile memory applications (NVM). However, various issues such as the switching mechanisms, switching uniformity, scalability and reproducibility have not yet been solved. In this paper, we discuss the recent progress of switching mechanisms and switching behaviors of various materials.
Scalable elements that can be switched between widely-separated non-volatile resistance states at very low power are desirable for applications in next generation memory and logic. One promising approach involves the use of solid ion-conducting films. A mobile metal ion-containing glassy electrolyte film sandwiched between an oxidizable metal layer and an inert electrode constitutes a device which...
This paper shows that that H plays a role in the forming of oxide RRAM which is derived from studies of both the electrical and physical properties of the oxides. Going forward, there is a clear need for additional studies that combine careful physical and electrical characterization of oxide and sulfide RRAM devices, as electrical measurements alone are ambiguous. If a thorough understanding of the...
In this paper, the characteristics and mechanism of the transition metal oxide (TMO) based resistive switching memory (RRAM) devices were addressed. The results show that doping in oxide matrix materials, electrode material, and operating mode of the set/reset process may significantly affect the resistive switching behaviors of RRAM devices. Optimizing the dopants and matrix materials, electrode...
This paper reports on the reliability issues encountered during the development of a dry ohmic switch fabricated in MEMS technology. Particularly, focus is made on electrical contact reliability. Contact degradation during hot switching tests has been noticed, and leads to switch lifetime limitation. In order to understand this phenomenon, characterizations have been performed on damaged switches...
Physical and electrical processes involved in the lifecycle failure of metal contacts in MEMS RF cantilever beam contact switches are of a great interest to switch designers. The main failure of MEMS contact switches occurs at the metal contacts. This paper describes a specially designed nanoindenter based experimental setup for characterizing the physics and mechanics of MEMS scale electrical contacts...
We present a fast and flexible method for the fabrication of nano-crossbar arrays with a feature size of 100 nm. TiO2 is integrated and electrically characterized as the nonvolatile resistively switching material. This structure serves as a key component for the investigation of novel high density nonvolatile resistive RAM cores.
Ultra-low current resistive switching in sputtered Cu/SiO2/Pt and Cu/SiO2/Ir structures was investigated. Both Cu and SiO2 are commonplace in silicon integrated circuits and hence the material system is CMOS compatible. The switching characteristics were very similar to those observed in other solid electrolytes so that the mechanism is assumed to be the same, i.e., based on the formation and rupture...
Resistance change memory (RRAM) is now attracting a lot of attention in parallel with phase change memory (PCM). Both memories are based on materials which exhibit nonvolatile changes in resistivity, through either the motion of charged species (RRAM) or through a crystalline-noncrystalline phase changes (PCM). Phase change memory is now viewed as a relatively near-term solution, while the RRAM has...
An on-chip buck converter with 3D chip stacking is proposed and the operation is experimentally verified. The manufactured converter achieves a maximum power efficiency of 62% for an output current of 70mA with a switching frequency of 200MHz and a 2x2mm on-chip LC output filter in 0.35mum CMOS. The use of glass epoxy interposer to increase the maximum power efficiency up to 71.3%, and the power efficiency...
To increase memory bandwidth with minimum area overhead, the new concept of 3D-stacked memory structure consisting of a small sense amplifier shared with a few 3D memory cells has been presented. The 16 bit 3D-stacked TiO2 memory chip was fabricated and demonstrated. The estimated bandwidth per unit area of 3D-stacked memory in sub-65 nm CMOS technology indicates that the 3D-stacked memory has potential...
A physical yet analytical phase change memory (PCM) model simultaneously accounting for thermal and electrical conductivities is presented. Due to the physics based nature of the model, the essential temperature from heating and cooling of PCM during operation is instantaneously updated. More importantly, the model can be applied to non-conventional circuit design technique. We show that for the first...
It is known that polymethylmethacrylate, PMMA, becomes conductive under shock loading. To develop an opening switch utilizing shock induced conduction, the reversibility of this process must be studied. It is suggested in literature that changes in electrical properties begin at pressures as low a ~2 GPa. Applying the minimum pressure necessary for conduction is desirable in order to maximize the...
Test switches used in protective relay schemes are selected based on quality, price and convenience features. The criteria selection assumes all the switches perform the basic functions they are intended to perform. This paper questions that basic assumption and performs an evaluation of existing offerings, and analyzes the impact of their performance in the power system.
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.