The Experts below are selected from a list of 13695 Experts worldwide ranked by ideXlab platform

Zhi-tang Song - One of the best experts on this subject based on the ideXlab platform.

  • crystal like glassy structure in sc doped bisbte ensuring excellent speed and power efficiency in Phase Change Memory
    ACS Applied Materials & Interfaces, 2020
    Co-Authors: Kun Ren, Tianjiao Xin, Mengjiao Xia, Shuaishuai Zhu, Guoxiang Wang, Zhi-tang Song
    Abstract:

    Phase Change Memory (PCM) is regarded as a promising technology for storage- class Memory and neuromorphic computing, owing to the excellent performances in operation speed, data retention, enduran...

  • carbon layer application in Phase Change Memory to reduce power consumption and atomic migration
    Materials Letters, 2017
    Co-Authors: Yan Cheng, Xin Chen, Keyuan Ding, Shilong Lv, Zhenguo Ji, Zhi-tang Song
    Abstract:

    Abstract Phase Change Memory (PCM) cells with carbon buffer layer have been fabricated. Carbon layer reduced the heat dissipation through upper electrode, increasing the energy efficiency of PCM, reducing the power consumption. The element distribution in PCM cell after 3 × 10 5 cycles proved that the carbon layer has successfully prevented atoms diffusion. After carbon layer being applied, the local high temperature during RESET in Phase Change material has been lowered. Hence, the higher viscosity at lower temperature has reduced atomic migration, beneficial to a good endurance.

  • a candidate zr doped sb2te alloy for Phase Change Memory application
    Applied Physics Letters, 2016
    Co-Authors: Yonghui Zheng, Zhi-tang Song, Sannian Song, Yan Cheng, Min Zhu, Qing Wang, Weili Liu, Songlin Feng
    Abstract:

    Here, Zr-doped Sb2Te alloy is proposed for Phase Change Memory (PCM). Zr-doping enhances the crystallization temperature and thermal stability of Sb2Te alloy effectively. Crystalline Zr2(Sb2Te)98 film is manifested as a single Phase without Phase separation and the growth of crystal grain is dramatically suppressed. The density Change of Zr2(Sb2Te)98 material between amorphous and crystalline is ∼2.65 ± 0.03%, which is much smaller than that of Ge2Sb2Te5 (6.5%). Phase Change Memory cells based on Zr2(Sb2Te)98 material can be reversibly switched by applying 40–400 ns width voltage pulses, and the reset current is relatively small when comparing with the prototypical Ge2Sb2Sb5 material. The resistance ON-OFF ratio of about 1.3 orders of magnitude is enough for figuring “0” and “1” out. Besides, endurance up to 4.1 × 104 cycles makes Zr-doped Sb2Te alloy a potential candidate for PCM.

  • a snake addressing scheme for Phase Change Memory testing
    Science in China Series F: Information Sciences, 2016
    Co-Authors: Zuolin Cheng, Xiaogang Chen, Zhi-tang Song
    Abstract:

    Phase Change Memory (PCM) is one of the most promising candidates for next generation nonvolatile Memory. However, PCM suffers from a variety of faults due to its special device structure and operation mechanism. A snake addressing scheme is introduced into the test algorithms of PCM to reduce the test time and excite proximity disturb faults more effectively. The March test algorithm with the proposed snake addressing scheme is less complex than most traditional test algorithms. In addition to conventional faults, it is capable of covering disturb and parasitic faults. Moreover, when incorporated with the sneak path testing method, it is able to test the read fault, read recovery fault, incomplete program fault 0, and false write fault.

  • ge2sb2te5 sb superlattice like thin film for high speed Phase Change Memory application
    Applied Physics Letters, 2015
    Co-Authors: Hua Zou, Sannian Song, Jianhao Zhang, Jianzhong Xue, Yongxing Sui, Li Yuan, Xiaoqin Zhu, Zhi-tang Song
    Abstract:

    In order to improve the operation speed of Phase Change Memory (PCM), superlattice-like Ge2Sb2Te5/Sb (SLL GST/Sb) thin films were prepared in a sputtering method to explore the suitability as an active material for PCM application. Compared with GST, SLL GST/Sb thin film has a lower crystallization temperature, crystallization activation energy, thermal conductivity, and smaller crystalline grain size. A faster SET/RESET switching speed (10 ns) and a lower operation power consumption (the energy for RESET operation 9.1 × 10−13 J) are obtained. In addition, GST/Sb shows a good endurance of 8.3 × 104 cycles.

Abu Sebastian - One of the best experts on this subject based on the ideXlab platform.

  • a Phase Change Memory model for neuromorphic computing
    Journal of Applied Physics, 2018
    Co-Authors: Manuel Le Gallo, Bipin Rajendran, Abu Sebastian, S R Nandakumar, Irem Boybat, Evangelos Eleftheriou
    Abstract:

    Phase-Change Memory (PCM) is an emerging non-volatile Memory technology that is based on the reversible and rapid Phase transition between the amorphous and crystalline Phases of certain Phase-Change materials. The ability to alter the conductance levels in a controllable way makes PCM devices particularly well-suited for synaptic realizations in neuromorphic computing. A key attribute that enables this application is the progressive crystallization of the Phase-Change material and subsequent increase in device conductance by the successive application of appropriate electrical pulses. There is significant inter- and intra-device randomness associated with this cumulative conductance evolution, and it is essential to develop a statistical model to capture this. PCM also exhibits a temporal evolution of the conductance values (drift), which could also influence applications in neuromorphic computing. In this paper, we have developed a statistical model that describes both the cumulative conductance evolution and conductance drift. This model is based on extensive characterization work on 10 000 Memory devices. Finally, the model is used to simulate the supervised training of both spiking and non-spiking artificial neuronal networks.

  • Monatomic Phase Change Memory
    Nature Materials, 2018
    Co-Authors: Martin Salinga, Riccardo Mazzarello, Ider Ronneberger, Vara Prasad Jonnalagadda, Iason Giannopoulos, Oana Cojocaru-mirédin, Manuel Le Gallo, Xuan Thang Vu, B. Kersting, Abu Sebastian
    Abstract:

    Phase Change Memory has been developed into a mature technology capable of storing information in a fast and non-volatile way1–3, with potential for neuromorphic computing applications4–6. However, its future impact in electronics depends crucially on how the materials at the core of this technology adapt to the requirements arising from continued scaling towards higher device densities. A common strategy to fine-tune the properties of Phase Change Memory materials, reaching reasonable thermal stability in optical data storage, relies on mixing precise amounts of different dopants, resulting often in quaternary or even more complicated compounds6–8. Here we show how the simplest material imaginable, a single element (in this case, antimony), can become a valid alternative when confined in extremely small volumes. This compositional simplification eliminates problems related to unwanted deviations from the optimized stoichiometry in the switching volume, which become increasingly pressing when devices are aggressively miniaturized9,10. Removing compositional optimization issues may allow one to capitalize on nanosize effects in information storage.Monatomic glasses formed by rapidly quenching Sb films from a molten state are shown to work as Phase Change materials for Memory applications at room temperature.

  • Monatomic Phase Change Memory
    Nature materials, 2018
    Co-Authors: Martin Salinga, Riccardo Mazzarello, Ider Ronneberger, Vara Prasad Jonnalagadda, Iason Giannopoulos, Oana Cojocaru-mirédin, Manuel Le Gallo, B. Kersting, Abu Sebastian
    Abstract:

    Phase Change Memory has been developed into a mature technology capable of storing information in a fast and non-volatile way, with potential for neuromorphic computing applications. However, its future impact in electronics depends crucially on how the materials at the core of this technology adapt to the requirements arising from continued scaling towards higher device densities. A common strategy to finetune the properties of Phase Change Memory materials, reaching reasonable thermal stability in optical data storage, relies on mixing precise amounts of different dopants, resulting often in quaternary or even more complicated compounds. Here we show how the simplest material imaginable, a single element (in this case, antimony), can become a valid alternative when confined in extremely small volumes. This compositional simplification eliminates problems related to unwanted deviations from the optimized stoichiometry in the switching volume, which become increasingly pressing when devices are aggressively miniaturized. Removing compositional optimization issues may allow one to capitalize on nanosize effects in information storage.

  • Temporal correlation detection using computational Phase-Change Memory
    Nature Communications, 2017
    Co-Authors: Abu Sebastian, Manuel Le Gallo, Tomas Tuma, Thomas Parnell, Nikolaos Papandreou, Lukas Kull, Evangelos Eleftheriou
    Abstract:

    Conventional computers based on the von Neumann architecture perform computation by repeatedly transferring data between their physically separated processing and Memory units. As computation becomes increasingly data centric and the scalability limits in terms of performance and power are being reached, alternative computing paradigms with collocated computation and storage are actively being sought. A fascinating such approach is that of computational Memory where the physics of nanoscale Memory devices are used to perform certain computational tasks within the Memory unit in a non-von Neumann manner. We present an experimental demonstration using one million Phase Change Memory devices organized to perform a high-level computational primitive by exploiting the crystallization dynamics. Its result is imprinted in the conductance states of the Memory devices. The results of using such a computational Memory for processing real-world data sets show that this co-existence of computation and storage at the nanometer scale could enable ultra-dense, low-power, and massively-parallel computing systems. New computing paradigms, such as in-Memory computing, are expected to overcome the limitations of conventional computing approaches. Sebastian et al. report a large-scale demonstration of computational Phase Change Memory (PCM) by performing high-level computational primitives using one million PCM devices.

  • Temporal correlation detection using computational Phase-Change Memory
    ArXiV, 2017
    Co-Authors: Abu Sebastian, Manuel Le Gallo, Tomas Tuma, Thomas Parnell, Nikolaos Papandreou, Lukas Kull, Evangelos Eleftheriou
    Abstract:

    For decades, conventional computers based on the von Neumann architecture have performed computation by repeatedly transferring data between their processing and their Memory units, which are physically separated. As computation becomes increasingly data-centric and as the scalability limits in terms of performance and power are being reached, alternative computing paradigms are searched for in which computation and storage are collocated. A fascinating new approach is that of computational Memory where the physics of nanoscale Memory devices are used to perform certain computational tasks within the Memory unit in a non-von Neumann manner. Here we present a large-scale experimental demonstration using one million Phase-Change Memory devices organized to perform a high-level computational primitive by exploiting the crystallization dynamics. Also presented is an application of such a computational Memory to process real-world data-sets. The results show that this co-existence of computation and storage at the nanometer scale could be the enabler for new, ultra-dense, low power, and massively parallel computing systems.

Songlin Feng - One of the best experts on this subject based on the ideXlab platform.

  • a candidate zr doped sb2te alloy for Phase Change Memory application
    Applied Physics Letters, 2016
    Co-Authors: Yonghui Zheng, Zhi-tang Song, Sannian Song, Yan Cheng, Min Zhu, Qing Wang, Weili Liu, Songlin Feng
    Abstract:

    Here, Zr-doped Sb2Te alloy is proposed for Phase Change Memory (PCM). Zr-doping enhances the crystallization temperature and thermal stability of Sb2Te alloy effectively. Crystalline Zr2(Sb2Te)98 film is manifested as a single Phase without Phase separation and the growth of crystal grain is dramatically suppressed. The density Change of Zr2(Sb2Te)98 material between amorphous and crystalline is ∼2.65 ± 0.03%, which is much smaller than that of Ge2Sb2Te5 (6.5%). Phase Change Memory cells based on Zr2(Sb2Te)98 material can be reversibly switched by applying 40–400 ns width voltage pulses, and the reset current is relatively small when comparing with the prototypical Ge2Sb2Sb5 material. The resistance ON-OFF ratio of about 1.3 orders of magnitude is enough for figuring “0” and “1” out. Besides, endurance up to 4.1 × 104 cycles makes Zr-doped Sb2Te alloy a potential candidate for PCM.

  • investigation of al sb se alloy for long data retention and low power consumption Phase Change Memory application
    Journal of Applied Physics, 2014
    Co-Authors: Zhonghua Zhang, Zhi-tang Song, Sannian Song, Yifeng Gu, Yan Cheng, Dong Zhou, Songlin Feng
    Abstract:

    Te-free Phase-Change material Al-Sb-Se is investigated and considered to be a promising candidate of storage medium for Phase Change Memory (PCM) application. Al0.49Sb2.19Se exhibits a higher crystallization temperature (∼222.7 °C), a larger crystallization activation energy (∼4.17 eV), and a better data retention (∼146.5 °C for 10 yr) in comparison with those of Ge2Sb2Te5. The uniformity of material distribution for crystalline film improves the reliability of Phase Change Memory. Al0.49Sb2.19Se-based Memory cell significantly shows lower power consumption for SET/RESET reversible switching than that of Ge2Sb2Te5-based one. Furthermore, PCM based on Al0.49Sb2.19Se shows endurance up to 3.5 × 103 cycles with stability resistance of about two orders of magnitude on/off ratio.

  • uniform ti doped sb2te3 materials for high speed Phase Change Memory applications
    Applied Physics Letters, 2014
    Co-Authors: Min Zhu, Zhi-tang Song, Kun Ren, Feng Rao, Sannian Song, Dongning Yao, Songlin Feng
    Abstract:

    Compared with pure Sb2Te3, Ti0.32Sb2Te3 (TST) Phase Change material has larger resistance ratio, higher crystallization temperature and better thermal stability. The sharp decrease in mobility is responsible for the increasing amorphous and crystalline sheet resistance. The uniform crystalline structure of TST film is very benefit for the endurance characteristic. The Set and Reset operation voltages for TST-based Phase Change Memory device are much lower than those of conventional Ge2Sb2Te5-based one. Remarkably, the device presents extremely rapid Set operation speed (∼6 ns). Furthermore, up to 1 × 106 programming cycles are obtained with stable Set and Reset resistances.

  • nitrogen doped sb rich si sb te Phase Change material for high performance Phase Change Memory
    Acta Materialia, 2013
    Co-Authors: Xilin Zhou, Zhi-tang Song, Kun Ren, Feng Rao, Bo Liu, Sannian Song, Yan Cheng, Songlin Feng
    Abstract:

    The effects of nitrogen doping on the Phase-Change performance of Sb-rich Si–Sb–Te materials are systemically investigated, focusing on the chemical state and the role of nitrogen upon crystallization. The tendency of N atoms to bond with Si (SiNx) in the crystalline film is analyzed by X-ray photoelectron spectroscopy. The microstructures of the materials mixed with Sb2Te crystal grains and amorphous Si/SiNx regions are elucidated via in situ transmission electron microscopy, from which a percolation behavior is demonstrated to possibly describe the random crystallization feature in the nucleation-dominated nanocomposite material. The Phase-Change Memory cells based on N-doped Sb-rich Si–Sb–Te materials display more stable and reliable electrical performance than the nitrogen-free ones. An endurance characteristic in the magnitude of 10 7 cycles of the Phase-Change Memory cells is realized with moderate nitrogen addition,

  • ti10sb60te30 for Phase Change Memory with high temperature data retention and rapid crystallization speed
    Applied Physics Letters, 2012
    Co-Authors: Min Zhu, Zhi-tang Song, Kun Ren, Feng Rao, Bo Liu, Daolin Cai, Sannian Song, Cheng Peng, Xilin Zhou, Songlin Feng
    Abstract:

    With a high crystallization temperature of 211 °C, Ti10Sb60Te30 Phase Change material exhibits a data retention of 10-yr at 137 °C, which is much better than that of usual Ge2Sb2Te5. No other Phase is formed in Ti10Sb60Te30 film except hexagonal Sb2Te Phase. For Ti10Sb60Te30-based Phase Change Memory cell, as short as 6 ns electric pulse can fulfill the Set operation, demonstrating an extremely rapid crystallization speed of Ti10Sb60Te30. The programming cycles can reach 2.2 × 104 with very short Set/Reset pulses of 100 ns/50 ns.

Evangelos Eleftheriou - One of the best experts on this subject based on the ideXlab platform.

  • a Phase Change Memory model for neuromorphic computing
    Journal of Applied Physics, 2018
    Co-Authors: Manuel Le Gallo, Bipin Rajendran, Abu Sebastian, S R Nandakumar, Irem Boybat, Evangelos Eleftheriou
    Abstract:

    Phase-Change Memory (PCM) is an emerging non-volatile Memory technology that is based on the reversible and rapid Phase transition between the amorphous and crystalline Phases of certain Phase-Change materials. The ability to alter the conductance levels in a controllable way makes PCM devices particularly well-suited for synaptic realizations in neuromorphic computing. A key attribute that enables this application is the progressive crystallization of the Phase-Change material and subsequent increase in device conductance by the successive application of appropriate electrical pulses. There is significant inter- and intra-device randomness associated with this cumulative conductance evolution, and it is essential to develop a statistical model to capture this. PCM also exhibits a temporal evolution of the conductance values (drift), which could also influence applications in neuromorphic computing. In this paper, we have developed a statistical model that describes both the cumulative conductance evolution and conductance drift. This model is based on extensive characterization work on 10 000 Memory devices. Finally, the model is used to simulate the supervised training of both spiking and non-spiking artificial neuronal networks.

  • Temporal correlation detection using computational Phase-Change Memory
    Nature Communications, 2017
    Co-Authors: Abu Sebastian, Manuel Le Gallo, Tomas Tuma, Thomas Parnell, Nikolaos Papandreou, Lukas Kull, Evangelos Eleftheriou
    Abstract:

    Conventional computers based on the von Neumann architecture perform computation by repeatedly transferring data between their physically separated processing and Memory units. As computation becomes increasingly data centric and the scalability limits in terms of performance and power are being reached, alternative computing paradigms with collocated computation and storage are actively being sought. A fascinating such approach is that of computational Memory where the physics of nanoscale Memory devices are used to perform certain computational tasks within the Memory unit in a non-von Neumann manner. We present an experimental demonstration using one million Phase Change Memory devices organized to perform a high-level computational primitive by exploiting the crystallization dynamics. Its result is imprinted in the conductance states of the Memory devices. The results of using such a computational Memory for processing real-world data sets show that this co-existence of computation and storage at the nanometer scale could enable ultra-dense, low-power, and massively-parallel computing systems. New computing paradigms, such as in-Memory computing, are expected to overcome the limitations of conventional computing approaches. Sebastian et al. report a large-scale demonstration of computational Phase Change Memory (PCM) by performing high-level computational primitives using one million PCM devices.

  • Temporal correlation detection using computational Phase-Change Memory
    ArXiV, 2017
    Co-Authors: Abu Sebastian, Manuel Le Gallo, Tomas Tuma, Thomas Parnell, Nikolaos Papandreou, Lukas Kull, Evangelos Eleftheriou
    Abstract:

    For decades, conventional computers based on the von Neumann architecture have performed computation by repeatedly transferring data between their processing and their Memory units, which are physically separated. As computation becomes increasingly data-centric and as the scalability limits in terms of performance and power are being reached, alternative computing paradigms are searched for in which computation and storage are collocated. A fascinating new approach is that of computational Memory where the physics of nanoscale Memory devices are used to perform certain computational tasks within the Memory unit in a non-von Neumann manner. Here we present a large-scale experimental demonstration using one million Phase-Change Memory devices organized to perform a high-level computational primitive by exploiting the crystallization dynamics. Also presented is an application of such a computational Memory to process real-world data-sets. The results show that this co-existence of computation and storage at the nanometer scale could be the enabler for new, ultra-dense, low power, and massively parallel computing systems.

  • Multilevel-Cell Phase-Change Memory: A Viable Technology
    IEEE Journal on Emerging and Selected Topics in Circuits and Systems, 2016
    Co-Authors: Aravinthan Athmanathan, Milos Stanisavljevic, Haralampos Pozidis, Nikolaos Papandreou, Evangelos Eleftheriou
    Abstract:

    In order for any non-volatile Memory (NVM) to be considered a viable technology, its reliability should be verified at the array level. In particular, properties such as high endurance and at least moderate data retention are considered essential. Phase-Change Memory (PCM) is one such NVM technology that possesses highly desirable features and has reached an advanced level of maturity through intensive research and development in the past decade. Multilevel-cell (MLC) capability, i.e., storage of two bits per cell or more, is not only desirable as it reduces the effective cost per storage capacity, but a necessary feature for the competitiveness of PCM against the incumbent technologies, namely DRAM and Flash Memory. MLC storage in PCM, however, is seriously challenged by phenomena such as cell variability, intrinsic noise, and resistance drift. We present a collection of advanced circuit-level solutions to the above challenges, and demonstrate the viability of MLC PCM at the array level. Notably, we demonstrate reliable storage and moderate data retention of 2 bits/cell PCM, on a 64 k cell array, at elevated temperatures and after 1 million SET/RESET endurance cycles. Under similar operating conditions, we also show feasibility of 3 bits/cell PCM, for the first time ever.

  • Reliable MLC data storage and retention in Phase-Change Memory after endurance cycling
    2013 5th IEEE International Memory Workshop, 2013
    Co-Authors: Haralampos Pozidis, Thomas Mittelholzer, C. Lam, Abu Sebastian, Nikolaos Papandreou, Matthew J. Brightsky, Evangelos Eleftheriou
    Abstract:

    For Phase-Change Memory to be considered a true universal Memory it would have to combine MLC storage, for low cost per bit, with adequately high endurance and at least moderate data retention. However, this appears to be particularly difficult to achieve, because of phenomena such as material segregation, which comes as an effect of cycling, and resistance drift, which is inherent in the amorphous Phase and affects the stability of stored data. We present a combination of a Memory cell with stable programming behavior over cycling, electrical sensing techniques and signal processing technologies, to demonstrate the viability of reliable, non-volatile, MLC storage in Phase-Change Memory cells after extended endurance cycling.

Sannian Song - One of the best experts on this subject based on the ideXlab platform.

  • a candidate zr doped sb2te alloy for Phase Change Memory application
    Applied Physics Letters, 2016
    Co-Authors: Yonghui Zheng, Zhi-tang Song, Sannian Song, Yan Cheng, Min Zhu, Qing Wang, Weili Liu, Songlin Feng
    Abstract:

    Here, Zr-doped Sb2Te alloy is proposed for Phase Change Memory (PCM). Zr-doping enhances the crystallization temperature and thermal stability of Sb2Te alloy effectively. Crystalline Zr2(Sb2Te)98 film is manifested as a single Phase without Phase separation and the growth of crystal grain is dramatically suppressed. The density Change of Zr2(Sb2Te)98 material between amorphous and crystalline is ∼2.65 ± 0.03%, which is much smaller than that of Ge2Sb2Te5 (6.5%). Phase Change Memory cells based on Zr2(Sb2Te)98 material can be reversibly switched by applying 40–400 ns width voltage pulses, and the reset current is relatively small when comparing with the prototypical Ge2Sb2Sb5 material. The resistance ON-OFF ratio of about 1.3 orders of magnitude is enough for figuring “0” and “1” out. Besides, endurance up to 4.1 × 104 cycles makes Zr-doped Sb2Te alloy a potential candidate for PCM.

  • ge2sb2te5 sb superlattice like thin film for high speed Phase Change Memory application
    Applied Physics Letters, 2015
    Co-Authors: Hua Zou, Sannian Song, Jianhao Zhang, Jianzhong Xue, Yongxing Sui, Li Yuan, Xiaoqin Zhu, Zhi-tang Song
    Abstract:

    In order to improve the operation speed of Phase Change Memory (PCM), superlattice-like Ge2Sb2Te5/Sb (SLL GST/Sb) thin films were prepared in a sputtering method to explore the suitability as an active material for PCM application. Compared with GST, SLL GST/Sb thin film has a lower crystallization temperature, crystallization activation energy, thermal conductivity, and smaller crystalline grain size. A faster SET/RESET switching speed (10 ns) and a lower operation power consumption (the energy for RESET operation 9.1 × 10−13 J) are obtained. In addition, GST/Sb shows a good endurance of 8.3 × 104 cycles.

  • Ni-doped GST materials for high speed Phase Change Memory applications
    Materials Research Bulletin, 2015
    Co-Authors: Yueqin Zhu, Zhi-tang Song, Zhonghua Zhang, Sannian Song, Huaqing Xie, Lanlan Shen, Bo Liu
    Abstract:

    Abstract In this paper, Ni-doped Ge 2 Sb 2 Te 5 (GST) was investigated for high speed Phase Change Memory applications. Compared with GST, Ni 0.3 Ge 2.8 Sb 2.2 Te 4.7 film exhibits a higher crystallization temperature (∼217 °C) and a better data retention ability (∼135 °C for 10 years). A reversible switching between set and reset can be realized by an electric pulse as short as 6-ns for Ni 0.3 Ge 2.8 Sb 2.2 Te 4.7 based Phase Change Memory. Furthermore, Ni 0.3 Ge 2.8 Sb 2.2 Te 4.7 based cell shows good endurance up to 1.5 × 10 4 SET–RESET cycles during endurance test.

  • investigation of al sb se alloy for long data retention and low power consumption Phase Change Memory application
    Journal of Applied Physics, 2014
    Co-Authors: Zhonghua Zhang, Zhi-tang Song, Sannian Song, Yifeng Gu, Yan Cheng, Dong Zhou, Songlin Feng
    Abstract:

    Te-free Phase-Change material Al-Sb-Se is investigated and considered to be a promising candidate of storage medium for Phase Change Memory (PCM) application. Al0.49Sb2.19Se exhibits a higher crystallization temperature (∼222.7 °C), a larger crystallization activation energy (∼4.17 eV), and a better data retention (∼146.5 °C for 10 yr) in comparison with those of Ge2Sb2Te5. The uniformity of material distribution for crystalline film improves the reliability of Phase Change Memory. Al0.49Sb2.19Se-based Memory cell significantly shows lower power consumption for SET/RESET reversible switching than that of Ge2Sb2Te5-based one. Furthermore, PCM based on Al0.49Sb2.19Se shows endurance up to 3.5 × 103 cycles with stability resistance of about two orders of magnitude on/off ratio.

  • uniform ti doped sb2te3 materials for high speed Phase Change Memory applications
    Applied Physics Letters, 2014
    Co-Authors: Min Zhu, Zhi-tang Song, Kun Ren, Feng Rao, Sannian Song, Dongning Yao, Songlin Feng
    Abstract:

    Compared with pure Sb2Te3, Ti0.32Sb2Te3 (TST) Phase Change material has larger resistance ratio, higher crystallization temperature and better thermal stability. The sharp decrease in mobility is responsible for the increasing amorphous and crystalline sheet resistance. The uniform crystalline structure of TST film is very benefit for the endurance characteristic. The Set and Reset operation voltages for TST-based Phase Change Memory device are much lower than those of conventional Ge2Sb2Te5-based one. Remarkably, the device presents extremely rapid Set operation speed (∼6 ns). Furthermore, up to 1 × 106 programming cycles are obtained with stable Set and Reset resistances.