Phase stabilities of Hf-Si-O and Zr-Si-O have been studied with first-principles and thermodynamic modeling. From the obtained thermodynamic descriptions, phase diagrams pertinent to thin film processing were calculated. We found that the relative stability of the metal silicates with respect to their binary oxides plays a critical role in silicide formation. It was observed that both the HfO$_2$/Si and ZrO$_2$/Si interfaces are stable in a wide temperature range and silicide may form at low temperatures, partially at the HfO$_2$/Si interface.
Ferroelectric hafnium zirconium oxide (HZO) thin films show significant promise for applications in ferroelectric random-access memory, ferroelectric field-effect transistors, and ferroelectric tunneling junctions. However, there are shortcomings in understanding ferroelectric switching, which is crucial in the operation of these devices. Here a computational model based on phase field method is developed to simulate the switching behavior of polycrystalline HZO thin films. Furthermore, we introduce a novel approach to optimize the effective Landau coefficients describing the free energy of HZ…
Ferroelectric oxides interfaced with transition metal dichalcogenides (TMDCs) offer a promising route toward ferroelectric-based devices due to lack of dangling bonds on the TMDC surface leading to a high-quality and abrupt ferroelectric/TMDC interface. In this work, the thermal stability of this interface is explored by first depositing hafnium zirconium oxide (HZO) directly on geological MoS2 and as-grown WSe2, followed by sequential annealing in ultra-high vacuum (UHV) over a range of temperatures (400-800 °C), and examining the interface through X-ray photoelectron spectroscopy (XPS). We s…
Access Rate-Dependent Endurance Behavior of Ferroelectric Hafnium Zirconium Oxide Capacitors
NaMLab gGmbH(NaMLab有限公司);Queen’s University Belfast(贝尔法斯特女王大学);Technical University Dresden(德累斯顿工业大学);Intel Foundry(英特尔代工);University Applied Sciences, Department of Applied Sciences and Mechatronics(应用科学大学应用科学与机电工程系)
Thermally stimulated depolarization in hafnium oxide: experiment and numerical simulation
Rzhanov Institute of Semiconductor Physics SB RAS(俄罗斯科学院西伯利亚分院半物理研究所);Herzen State Pedagogical University(赫尔岑国立师范大学);Nikolaev Institute of Inorganic Chemistry SB RAS(俄罗斯科学院西伯利亚分院尼古拉耶夫无机化学研究所);Novosibirsk State Technical University(新西伯利亚国立技术大学)
Investigation of a high-entropy oxide photocatalyst for hydrogen generation by first-principles calculations coupled with experiments: Significance of electronegativity
The discovery of ferroelectric HfO2 in thin films and more recently in bulk is an important breakthrough because of its silicon-compatibility and unexpectedly persistent polarization at low dimensions, but the origin of its ferroelectricity is still under debate. The stabilization of the metastable polar orthorhombic phase was often considered as the cumulative result of various extrinsic factors such as stress, grain boundary, and oxygen vacancies as well as phase transition kinetics during the annealing process. We propose a novel mechanism to stabilize the polar orthorhombic phase over the …
Hafnium oxide (HfO2)-based ferroelectrics offer remarkable promise for memory and logic devices in view of their compatibility with traditional silicon CMOS technology, high switchable polarization, good endurance and thickness scalability. These factors have led to steep rise in research on this class of materials over the past number of years. At the same time, only a few reports on the direct sensing of nanoscale ferroelectric properties exist, with many questions remaining regarding the emergence of ferroelectricity in these materials. While piezoresponse force microscopy (PFM) is ideally …
Stress-Induced Ferroelectricity in Hafnium Oxide Core-Shell Nanoparticles
Institute of Physics of the National Academy of Sciences of Ukraine(乌克兰国家科学院物理研究所);Frantsevich Institute for Problems in Materials Science of the National Academy of Sciences of Ukraine(乌克兰国家科学院弗拉特谢维奇材料科学问题研究所);Department of Materials Science and Engineering, University of Tennessee, Knoxville(田纳西大学诺克斯维尔分校材料科学与工程系);Zone 5 Technologies(第五区技术公司)
Dielectric Deposition Enhanced Crystallization in Atomic-Layer-Deposited Indium Oxide Transistors Achieving High Gated-Hall Mobility Exceeding 100 cm2/Vs at Room Temperature
Barium zirconium sulfide (BaZrS3) is an earth-abundant and environmentally friendly chalcogenide perovskite with promising properties for various energy conversion applications. Recently, sulfurization of oxide precursors has been suggested as a viable solution for effective synthesis, especially from the perspective of circumventing the difficulty of handling alkali earth metals. In this work, we explore in detail the synthesis of BaZrS3 from Ba-Zr-O oxide precursor films sulfurized at temperatures ranging from 700 °C to 1000 °C. We propose a formation mechanism of BaZrS3 based on a two-step …
4d transition metal oxides have emerged as promising materials for numerous applications including high mobility electronics. SrNbO$_{3}$ is one such candidate material, serving as a good donor material in interfacial oxide systems and exhibiting high electron mobility in ultrathin films. However, its synthesis is challenging due to the metastable nature of the d$^{1}$ Nb$^{4+}$ cation and the limitations in the delivery of refractory Nb. To date, films have been grown primarily by pulsed laser deposition (PLD), but development of a means to grow and stabilize the material via molecular beam e…
Since the 1960's when Gordon Moore proposed that the transistor density in our electronic devices should double every two years while the cost is halved, the semiconductor industry has taken this statement to heart. Over the last few decades, no other industry has seen growth even comparably close to that experienced by the semiconductors industry. This has all been made possible by the unbroken string of ingenious breakthroughs by brilliant minds that have been working tirelessly to shrink down transistors. The latest of which is the use of high-k dielectrics and a return to metal gates combi…