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Area‐selective deposition (ASD) is a forefront nanopatterning technique gaining substantial attention in the semiconductor industry. While current research primarily addresses single‐material ASD, exploring multi‐material ASD is essential for mitigating complexity in advanced nanopatterning. This study describes molybdenum hexafluoride (MoF₆)‐mediated fluorination/passivation of the hydroxylated SiO₂(SiO₂‒OH) at 250 °C as a new method to pacify nucleation during subsequent ZnO and TiO₂atomic layer deposition (ALD). In contrast, Al₂O₃ALD is not passivated on the fluorinated SiO₂(SiO₂‒F). The study further shows that Mo ALD using MoF₆and silane (1 wt% SiH₄in Ar) selectively proceeds on hydrogen‐terminated Si (Si‒H), whereas SiO₂‒OH becomes fluorine‐passivated without observable Mo deposition. This enables subsequent ZnO and TiO₂ASD on Mo versus SiO₂‒F, as confirmed by X‐ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and scanning transmission electron microscopy (STEM). Proposed growth and inhibition mechanisms highlight the importance of the metal oxide precursor in achieving selectivity. Taken together, self‐aligned Mo/ZnO and Mo/TiO₂nanoribbons are demonstrated on coplanar nanoscale Si‒H/SiO₂‒OH patterns by sequentially integrating two individual ASD processes: 1) Mo ASD on Si‒H versus SiO₂‒OH; and 2) ZnO or TiO₂ASD on Mo versus SiO₂‒F. This work highlights the potential for this approach in new ASD systems.

 

Ferroelectric hafnium-zirconium oxide (HZO) is an excellent candidate for low-power non-volatile memory applications due to its demonstrated ferroelectricity at the nanoscale and compatibility with silicon-based technologies. The interface of HZO in contact with its electrode, typically TiN in a metal–ferroelectric–metal (MFM) capacitor configuration, is of particular interest because factors, such as volume confinement, impurity concentration, interfacial layers, thermal expansion mismatch, and defect trapping, are believed to play a crucial role in the ferroelectric performance of HZO-based devices. Processing variables, such as precursor type, oxygen source, dose duration, and deposition temperature, are known to strongly affect the quality of the oxide–metal interface. However, not many studies have focused on the effect of breaking or maintaining vacuum during MFM deposition. In this study, sequential, no-atmosphere processing (SNAP) is employed to avoid atmospheric exposure, where electrode TiN and ferroelectric HZO are deposited sequentially in the atomic layer deposition chamber without breaking vacuum. The effect of breaking vacuum during the sequential deposition steps is elucidated by fabricating and characterizing MFM capacitors with and without intentional vacuum breaks prior to the deposition of the HZO and top TiN. Using x-ray photoelectron spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS), we reveal that breaking vacuum after bottom TiN electrode deposition leads to interfacial oxidation and increased carbon contamination, which preferentially stabilizes the non-ferroelectric tetragonal phase and lead to diminished remanent polarization. Avoiding carbon impurities and interfacial TiOx at the HZO and TiN interface using SNAP leads to heightened remanent polarization, reduced leakage current density, and elimination of the wake-up effect. Our work highlights the effect of vacuum breaking on the processing-structure-properties of HZO-based capacitors, revealing that maintaining vacuum can significantly improve ferroelectric properties.

 

Abstract Hf 0.5 Zr 0.5 O 2 (HZO) thin films are promising candidates for non-volatile memory and other related applications due to their demonstrated ferroelectricity at the nanoscale and compatibility with Si processing. However, one reason that HZO has not been fully scaled into industrial applications is due to its deleterious wake-up and fatigue behavior which leads to an inconsistent remanent polarization during cycling. In this study, we explore an interfacial engineering strategy in which we insert 1 nm Al 2 O 3 interlayers at either the top or bottom HZO/TiN interface of sequentially deposited metal-ferroelectric-metal capacitors. By inserting an interfacial layer while limiting exposure to the ambient environment, we successfully introduce a protective passivating layer of Al 2 O 3 that provides excess oxygen to mitigate vacancy formation at the interface. We report that TiN/HZO/TiN capacitors with a 1 nm Al 2 O 3 at the top interface demonstrate a higher remanent polarization (2P r ∼ 42 μ C cm −2 ) and endurance limit beyond 10 8 cycles at a cycling field amplitude of 3.5 MV cm −1 . We use time-of-flight secondary ion mass spectrometry, energy dispersive spectroscopy, and grazing incidence x-ray diffraction to elucidate the origin of enhanced endurance and leakage properties in capacitors with an inserted 1 nm Al 2 O 3 layer. We demonstrate that the use of Al 2 O 3 as a passivating dielectric, coupled with sequential ALD fabrication, is an effective means of interfacial engineering and enhances the performance of ferroelectric HZO devices. 

Ferroelectric (Hf,Zr)O2 thin films have attracted increased interest from the ferroelectrics community and the semiconductor industry due to their ability to exhibit ferroelectricity at nanoscale dimensions. The properties and performance of the ferroelectric (Hf,Zr)O2 films generally depend on various factors such as surface energy (e.g., through grain size or thickness), defects (e.g., through dopants, oxygen vacancies, or impurities), electrodes, interface quality, and preferred crystallographic orientation (also known as crystallographic texture or simply texture) of grains and/or domains. Although some factors affecting properties and performance have been studied extensively, the effects of texture on the material properties are still not understood. Here, the influence of texture of the bottom electrode and Hf0.5Zr0.5O2 (HZO) films on properties and performance is reported. The uniqueness of this work is the use of a consistent deposition process known as Sequential, No-Atmosphere Processing (SNAP) that produces films with different preferred orientations yet minimal other differences. The results shown in this study provide both new insight on the importance of the bottom electrode texture and new fundamental processing-structure–property relationships for the HZO films.

 

Two-dimensional (2D) molybdenum ditelluride (MoTe 2 ) is an interesting material for fundamental study and applications, due to its ability to exist in different polymorphs of 2H, 1T, and 1T′, their phase change behavior, and unique electronic properties. Although much progress has been made in the growth of high-quality flakes and films of 2H and 1T′-MoTe 2 phases, phase-selective growth of all three phases remains a huge challenge, due to the lack of enough information on their growth mechanism. Herein, we present a novel approach to growing films and geometrical-shaped few-layer flakes of 2D 2H-, 1T-, and 1T′-MoTe 2 by atmospheric-pressure chemical vapor deposition (APCVD) and present a thorough understanding of the phase-selective growth mechanism by employing the concept of thermodynamics and chemical kinetics involved in the growth processes. Our approach involves optimization of growth parameters and understanding using thermodynamical software, HSC Chemistry. A lattice strain-mediated mechanism has been proposed to explain the phase selective growth of 2D MoTe 2 , and different chemical kinetics-guided strategies have been developed to grow MoTe 2 flakes and films. 

Current approaches to create zirconium‐based metal–organic framework (MOF) fabric composites for catalysis, water purification, wound healing, gas sorption, and other applications often rely on toxic solvents, long reaction/post processing times, and batch methods hindering process scalability. Here, a novel mechanism was reported for rapid UiO‐66‐NH₂synthesis in common low‐boiling‐point solvents (water, ethanol, and acetic acid) and revealed acid–base chemistry promoting full linker dissolution and vapor‐based crystallization. The mechanism enabled scalable roll‐to‐roll production of mechanically resilient UiO‐66‐NH₂fabrics with superior chemical protective capability. Solvent choice and segregated spray delivery of organic linker and metal salt MOF precursor solutions allowed for rapid MOF nucleation on the fiber surface and decreased the energy and time needed for post‐processing, producing an activated composite in less than 165 min, far outpacing conventional MOF‐fabric synthesis approaches. The MOF‐fabric hydrolyzed and blocked permeation of the chemical warfare agent soman, outperforming the protection‐standard activated carbon cloth. This work presents both chemical insights into Zr‐MOF powder and fabric composite formation by a rapid, industrially relevant approach and demonstrates its practicality and affordability for high‐performing personal protective equipment.