Dopant and Defect Physics for Device Optimization for Hafnium Oxide based Devices

用铁电氧化钨实现的器件与硅兼容，能效高，并且可以经济高效地集成到用于传感器、非易失性存储器、逻辑和神经形态应用的高级技术节点中。目前，Hf_xZ_(1-x)O_2为制备大剩余极化超薄铁电薄膜提供了最宽的化学计量比窗口。尽管如此，该薄膜需要氧空位(VO)来稳定铁电相，并且存在可靠性问题。VO浓度很难控制，可能会影响极化稳定性等电学特性，危及基于Hafnia的存储器和低功率逻辑的前景。另一种选择是从化学计量的、准无空位的哈夫纳开始，并使用合适的掺杂剂来优化铁电性能。这将具有比在HfxZr1-xO2中相当不受控制的VO的产生更具重现性的显著优点。我们将通过从头计算和相场模拟研究选择性和可控掺杂的Hafina的原子和电子结构来探索这种可能性，以描述掺杂调制的原子和电子结构对铁电性质的影响。将考虑一系列掺杂剂、浓度和工艺条件，以提供掺杂剂化学和铁电性能之间的相关性的初步评估。选定的材料将在大面积电容器上进行表征，并通过连续的模拟、处理和表征迭代进行优化。然后，它们将被集成到定标电容器阵列中，以提供具有统计意义的铁电电容器性能结果。在基本水平上，D3PO将更好地了解掺杂对局域化学、电子结构、相组成的影响，以及它们对材料和铁电参数的影响，包括再结晶温度和剩余极化。然后，我们将详细阐述基于真实器件的物理模型，使用从头计算模拟以及结构和电学表征获得的参数，通过统计分析来预测使用无空位掺杂的Hafnia材料的唤醒、耐久、保持、泄漏和击穿等关键指标。

Devices realized with ferroelectric hafnium oxide are silicon compatible, power-efficient, and can be cost-effectively integrated into advanced technology nodes for sensor, nonvolatile memory, logic, and neuromorphic applications. Currently, hafnium-zirconium mixed oxide (HfxZr1-xO2) offers the widest stoichiometry window for fabricating ultrathin ferroelectric films with large remanent polarization. Still, the film requires oxygen vacancies (VO) to stabilize the ferroelectric phase and has reliability issues. VO concentration is difficult to control and can affect electrical properties such as polarization stability, jeopardizing the prospect of hafnia-based memory and low-power logic. An alternative could be to start from stoichiometric, quasi-vacancy-free hafnia and use suitable dopants to optimize the ferroelectric properties. This would have the significant advantage of being more reproducible than the rather uncontrolled generation of VO in HfxZr1-xO2. We will explore this possibility by studying the atomic and electronic structure of selectively and controllably doped hafnia using ab initio calculations and phase-field simulations to describe the influence of the dopant modulated atomic and electronic structure on the ferroelectric properties. A range of dopants, concentrations, and process conditions will be considered to provide an initial assessment of the correlations between dopant chemistry and the ferroelectric properties. The chosen materials will be characterized on large area capacitors and optimized by successive simulation, processing, and characterization iterations. Then they will be integrated into scaled capacitor arrays to provide statistically significant results on ferroelectric capacitor performance. At a fundamental level, D3PO will give a better understanding of the influence of dopants on local chemistry, electronic structure, phase composition, and their effects on material and ferroelectric parameters, including recrystallization temperature and remanent polarization. We will then elaborate physical models based on real devices, using parameters obtained from ab initio simulations and structural and electrical characterization to predict, through statistical analysis, key metrics such as wake-up, endurance, retention, leakage, and breakdown using vacancy-free doped hafnia.