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

用于氧化铪基器件的器件优化的掺杂剂和缺陷物理学

• 批准号: 505873959
• 负责人: Professor Dr. Alfred Kersch
• 金额: --
• 依托单位: Nanoelectronics Materials Laboratory (NaMLab)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/505873959?language=en
• 关键词: Dopant; Defect; Physics; Device; Optimization

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.

使用铁电氧化铪实现的器件具有硅兼容性、高能效，并且可以经济高效地集成到传感器、非易失性存储器、逻辑和神经形态应用的先进技术节点中。目前，铪锆混合氧化物（HfxZr1-xO2）为制造具有大剩余极化的超薄铁电薄膜提供了最宽的化学计量窗口。尽管如此，该薄膜仍需要氧空位（VO）来稳定铁电相，并且存在可靠性问题。 VO浓度难以控制，并且会影响极化稳定性等电性能，危及基于铪的存储器和低功耗逻辑的前景。另一种选择是从化学计量、准无空位的二氧化铪开始，并使用合适的掺杂剂来优化铁电性能。与 HfxZr1-xO2 中不受控制的 VO 生成相比，这具有更高的可重复性的显着优势。 我们将通过从头计算和相场模拟研究选择性可控掺杂二氧化铪的原子和电子结构来探索这种可能性，以描述掺杂剂调制的原子和电子结构对铁电性能的影响。将考虑一系列掺杂剂、浓度和工艺条件，以对掺杂剂化学和铁电性质之间的相关性进行初步评估。所选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，它们将被集成到按比例缩放的电容器阵列中，以提供有关铁电电容器性能的统计上显着的结果。从根本上讲，D3PO 将帮助我们更好地了解掺杂剂对局部化学、电子结构、相组成的影响，及其对材料和铁电参数（包括再结晶温度和剩余极化）的影响。然后，我们将基于真实器件详细阐述物理模型，使用从头开始模拟以及结构和电气表征中获得的参数，通过统计分析来预测关键指标，例如使用无空位掺杂二氧化铪的唤醒、耐久性、保留、泄漏和击穿。