随着现代信息技术的快速发展，需要存储的数据信息量在不断增长，促使工业界和学术界不断发展新型的存储器技术来满足不断扩大的市场需求。磁阻存储器、相变存储器、阻变存储器和铁电存储器等新型的存储器被认为是下一代非挥发性存储器的候选者，受到广泛的关注。其中，铁电存储器利用的是铁电晶体所固有的一种偏振极化特性，具有高速度、低功耗、高可靠性的优点，成为下一代非挥发性存储器的有力竞争者之一。然而传统铁电材料与标准CMOS工艺兼容性差问题和尺寸微缩难的问题制约着铁电存储器的发展。传统铁电材料只有在几十纳米甚至更大的厚度才能够保持稳定的剩余极化量和较小的漏电流，若减小厚度则会导致极化状态不稳定，薄膜厚度限制了传统铁电器件的可缩小性。此外，传统铁电材料的制备温度，退火温度较高而且含有Pb、Bi等污染性元素，与CMOS工艺不兼容。2011年，掺杂HfO₂薄膜铁电性的发现，有望解决传统铁电存储器的尺寸微缩和CMOS兼容性方面的难题。掺杂HfO₂铁电材料在～10 nm厚度就可以保持稳定的极化状态，而且HfO₂本身作为高k介质材料已经被用到处理器的应用中，已经被广泛用于Si基CMOS器件中，材料特性和制备工艺成熟。因此掺杂HfO₂铁电材料逐渐成为铁电存储器研究领域的新热点。 近几年来，越来越多的掺杂HfO₂薄膜材料体系被逐渐发现并研究，其中Zr掺杂的HfO₂具有铁电性的掺杂范围最大而且退火温度最低，最易于制备。本论文选择以Zr掺杂HfO₂铁电材料为基础，在铁电器件性能调控及提高耐久性等方面开展了相关的研究工作，主要分为以下几个方面的内容： 稳定的材料制备工艺是我们开展铁电存储器相关研究的基础，第一部分的主要工作是开发了稳定可靠的Zr掺杂HfO₂薄膜，并阐明了铁电特性与相关工艺参数的依赖关系。通过对掺杂比例、薄膜厚度、退火温度等影响因素进行探索，确定Zr掺杂HfO₂铁电材料的最佳生长工艺。得到的工艺条件稳定且可重复，制备的TiN／HZO／TiN铁电电容，窗口大、耐久性高、可靠性高。 其次是提高Zr掺杂HfO₂铁电电容耐久性的研究。虽然，与传统铁电材料相比，掺杂HfO₂铁电材料在尺寸和CMOS工艺兼容性方面存在优势，但是由于其矫顽场接近击穿电场，容易发生击穿，所以掺杂HfO₂铁电材料的耐久性不如传统铁电器件耐久性高。针对此问题，我们采用惰性电极Ru代替常用的TiN电极，减小退火过程电极元素的扩散，同时减小界面处氧空位的浓度，提高了击穿电场，减小了漏电流，提高Zr掺杂HfO₂铁电电容的可循环次数高达1.2×10¹¹次。 采用不同物性的电极对Zr掺杂HfO₂铁电电容存储器的存储窗口和转变电压实现了调控。通过不同热膨胀系数的电极实现了对铁电电容存储器存储窗口的调控，在退火过程中，热膨胀系数越小的电极产生的夹持力越大，可以抑制非铁电m-相的生长，促进铁电o-相的转变。通过不同功函数的电极实现了对铁电电容阈值电压的调控，上下电极功函数差引入内建电场，而所引入内建电场的大小和极性决定了矫顽场的偏移量大小和偏移方向。既提高了铁电电容存储器在实际应用中的电极选择灵活性，也为铁电电容存储器的性能调控提供了一种可行方案。 铁电电阻型器件是通过测量电阻来读取铁电薄膜的极化状态，不会改变原有的极化状态，是一种高效无损的读取方式，因此铁电电阻型器件是高密度铁电存储的潜在候选者。我们采用W／HZO／W栓MFM结构制备了铁电二极管。通过铁电极化调节金属／铁电体界面的势垒，表现出二极管整流特性，而且在外电场作用下铁电极化方向会发生反转进而可以将二极管的整流方向反向，通过铁电极化实现了双向可调二极管特性，开关比为10³，保持10⁴s。 关键词：非挥发性存储器，铁电存储器，耐久性，性能调控，铁电可变二极管

 With the rapid development of information technology, the amount of data increases constantly, the expanding market prompts the industry and academia to develop new memory technology. New non-volatile storage technology such as magnetoresistive random access memory, phase random access memory, resistance random access memory and ferroelectric random access memory are considered as candidates for the next generation of non-volatile memory. Among these types of non-volatile memory, ferroelectric random access memory stores information through the inherent characteristic of polarization in ferroelectric crystals, and been considered as the most promising candidate for the next generation non-volatile memory due to its advantages of high speed, low power consumption and high reliability. However, the scalability and the incompatibility with standard CMOS process of traditional ferroelectric materials restrict the further development of ferroelectric memory. Only thick traditional ferroelectric materials can maintain stable remnant polarization and small leakage current (about tens of nanometers or even larger), the polarization state will be unstable if the thickness decreases. The film thickness limits the scalability of traditional ferroelectric memory. In addition, the high preparation temperature, high annealing temperature and polluting elements of traditional ferroelectric materials, such as Pb and Bi, which are incompatible with standard CMOS process. In 2011, the doped HfO₂ ferroelectricity thin film was found and been expected to solve the scalability and the CMOS incompatibility problems of traditional ferroelectric memory. Doped HfO₂ ferroelectric materials can keep stable polarization state with about 10 nm thickness, and HfO₂ itself as high k material has been used in the Si-basied CMOS devices, the preparation technology of HfO₂ are mature. Therefore, doped HfO₂ ferroelectric materials have gradually become a new research focus of ferroelectric memory. In recent years, more and more doped HfO₂ ferroelectric materials have been discovered and studied, among which Zr doped HfO₂ is the easiest to prepare due to its largest ferroelectric doping range and the lowest annealing temperature. This paper focuses on the improvement of endurance and the performance regulation of ferroelectric memory based on Zr doped HfO₂ ferroelectric materials, which is mainly divided into the following aspects: Stable material preparation process is the basis of our research on ferroelectric memory. The first part of work is to develop stable and reliable Zr doped HfO₂ thin film, and to clarify the dependence between ferroelectric properties and related process parameters. The optimized depositional process of Zr doped HfO₂ ferroelectric materials was determined by exploring the influence factors, such as doping ratio, film thickness and annealing temperature, The optimized process conditions are stable and repeatable, and the prepared TiN/HZO/TiN ferroelectric capacitors have large windows, high endurance and high reliability. Secondly, the improvement of endurance of ferroelectric memory based on Zr doped HfO₂ ferroelectric materials is reserched. Compared with traditional ferroelectric materials, doped HfO₂ ferroelectric materials have advantages in scalability and the compatibility with CMOS process. However, the breakdown occurs easier in doped HfO₂ ferroelectric materials than traditional ferroelectric materials, because its coercive field and electric field are close. So. the endurance of doped HfO₂ ferroelectric materials is not as high as that of traditional ferroelectric materials. In order to solve this problem, the inert electrode Ru was used to replace the commonly used TiN electrode. The diffusion of electrode elements was reduced during the annealing process, at the same time, the concentration of oxygen vacancy at the interface was reduced. Consequently, the breakdown electric field was enchanced and the leakage current was reduced, the number of cycles of Zr doped HfO₂ ferroelectric capacitor was increased to 1.2×10¹¹ cycles. The storage window and switching voltage of Zr doped HfO₂ ferroelectric capacitors are s regulated by different electrodes. The electrode with different thermal expansion coefficient can regulate the storage window of ferroelectric capacitor memory. In the annealing process, the greater clamping force is generated by the electrode with smaller thermal expansion coefficient, which can inhibit the growth of non-ferroelectric phase (m-phase) and promote the transformation to ferroelectric o-phase. The switching voltage of ferroelectric capacitance is regulated by electrodes with different work functions. The difference of work functions between top and bottom electrodes introduces a built-in electric field, the magnitude and polarity of the built-in electric field determines the deviation and direction of the coercive field. It not only improves the flexibility of electrode selection in practical application of ferroelectric capacitor memory, but also provides a feasible scheme for the performance regulation of ferroelectric capacitor memory. Ferroelectric resistive devices read the polarization state of ferroelectric thin films by measuring the resistance, which will not change the original polarization state. It is an efficient and lossless reading method. Therefore, ferroelectric resistive devices are potential candidates for high-density ferroelectric storage. We fabricate ferroelectric diode by W/HZO/W plug MFM structure. The interfacial potential barrier of metal/ferroelectric is adjusted by the ferroelectric polarization, shows the rectifier characteristics of diode. The ferroelectric polarization can be flipped by the applied electric field, at the same time, the rectifier direction of diode is reversed. The sw'itchable ferroelectric diode is realized by the switchable ferroelectric polarization, on/off ration is 10³, retention is 10⁴ s. Key Words: Non-volatile memory, Ferroelectric random access memory, Endurance, Performance regulation, switchable Ferroelectric diode