• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文学位 >Titanium oxide nonvolatile memory device and its application.
【24h】

Titanium oxide nonvolatile memory device and its application.

机译：氧化钛非易失性存储器件及其应用。

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In recent years, the semiconductor memory industry has seen an ever-increasing demand for nonvolatile memory (NVM), which is fueled by portable consumer electronic applications like the mobile phone and MP3 player. FLASH memory has been the most widely used nonvolatile memories in these systems, and has successfully kept up with CMOS scaling for many generations. However, as FLASH memory faces major scaling challenges beyond 22nm, non-charge-based nonvolatile memories are widely researched as candidates to replace FLASH. Titanium oxide (TiOx) nonvolatile memory device is considered to be a promising choice due to its controllable nonvolatile memory switching, good scalability, compatibility with CMOS processing and potential for 3D stacking. However, several major issues need to be overcome before TiOx NVM device can be adopted in manufacturing.;First, there exists a highly undesirable high-voltage stress initiation process (FORMING) before the device can switch between high and low resistance states repeatedly. By analyzing the conductive behaviors of the memory device before and after FORMING, we propose that FORMING involves breaking down an interfacial layer between its Pt electrode and the TiOx thin film, and that FORMING is not needed if the Pt-TiOx interface can be kept clean during fabrication.;An in-situ fabrication process is developed for cross-point TiOx NVM device, which enables in-situ deposition of the critical layers of the memory device and thus achieves clean interfaces between Pt electrodes and TiOx film. Testing results show that FORMING is indeed eliminated for memory devices made with the in-situ fabrication process. It verifies the significance of in-situ deposition without vacuum break in the fabrication of TiOx NVM devices.;Switching parameters statistics of TiOx NVM devices are studied and compared for unipolar and bipolar switching modes. RESET mechanisms are found to be different for the two switching modes: unipolar switching can be explained by thermal dissolution model, and bipolar switching by local redox reaction model.;Since it is generally agreed that the memory switching of TiOx NVM devices is based on conductive filaments, reusability of these conductive filaments becomes an intriguing issue to determine the memory device's endurance. A 1X3 cross-point test structure is built to investigate whether conductive filaments can be reused after RESET. It is found that the conductive filament is destroyed during unipolar switching, while can be reused during bipolar switching. The result is a good indication that bipolar switching should have better endurance than unipolar switching.;Finally a novel application of the two-terminal resistive switching NVM devices is demonstrated. To reduce SRAM leakage power, we propose a nonvolatile SRAM cell with two back-up NVM devices. This novel cell offers nonvolatile storage, thus allowing selected blocks of SRAM to be powered down during operation. There is no area penalty in this approach. Only a slight performance penalty is expected.
机译：近年来，半导体存储行业对非易失性存储器（NVM）的需求不断增长，非易失性存储器（NVM）受到便携式消费电子应用（如移动电话和MP3播放器）的推动。 FLASH存储器一直是这些系统中使用最广泛的非易失性存储器，并且已经成功地与CMOS缩放保持了几代之久。然而，由于闪存面临超过22nm的重大扩展挑战，因此广泛研究基于非电荷的非易失性存储器来替代闪存。氧化钛（TiOx）非易失性存储设备由于其可控的非易失性存储开关，良好的可扩展性，与CMOS处理的兼容性以及3D堆叠的潜力而被认为是有前途的选择。然而，在制造中采用TiOx NVM器件之前，需要克服几个主要问题。首先，在器件可以反复在高阻状态和低阻状态之间切换之前，存在着非常不希望的高压应力引发过程（FORMING）。通过分析存储器件在形成之前和之后的导电行为，我们建议形成涉及破坏其Pt电极和TiOx薄膜之间的界面层，如果可以保持Pt-TiOx界面清洁，则不需要形成针对交叉点TiOx NVM器件开发了一种原位制造工艺，该工艺可以在原位沉积存储器件的关键层，从而实现Pt电极与TiOx膜之间的清洁界面。测试结果表明，对于采用原位制造工艺制造的存储设备，确实消除了FORMING。验证了在不破坏真空的情况下原位沉积在TiOx NVM器件制造中的重要性。研究了TiOx NVM器件的开关参数统计，并比较了单极性和双极性开关模式。发现RESET机制在两种开关模式下是不同的：单极性开关可以通过热溶解模型来解释，而双极性开关可以通过局部氧化还原反应模型来解释;因为人们普遍认为TiOx NVM器件的存储开关是基于导电的对于细丝，这些导电细丝的可重复使用性成为确定存储设备耐久性的一个引人入胜的问题。建立了1X3交叉点测试结构，以研究RESET之后是否可以重复使用导电丝。发现导电灯丝在单极开关期间被破坏，而在双极开关期间可以被重复使用。结果很好地表明了双极性开关应比单极性开关具有更好的耐久性。最后，说明了双端电阻式开关NVM器件的新型应用。为了降低SRAM的泄漏功率，我们提出了具有两个备用NVM器件的非易失性SRAM单元。这种新颖的单元提供了非易失性存储，因此允许在操作期间关闭SRAM的选定块。这种方法没有面积损失。预计只会有轻微的性能损失。

著录项

  • 作者

    Wang, Wei.;

  • 作者单位

    Stanford University.;

  • 授予单位 Stanford University.;
  • 学科 Engineering Electronics and Electrical.;Engineering Materials Science.
  • 学位 Ph.D.
  • 年度 2009
  • 页码 103 p.
  • 总页数 103
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 无线电电子学、电信技术;工程材料学;
  • 关键词

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号