A 50 × 50 mm 2 copper target is sputtered by an ion beam at angles of incidence from 0 ° to 90 °. The resulting sputter plumes are characterized directionally resolved using a compact and maneuverable force probe. It measures the momentum flux of particles released due to sputtering or reflection inside the sputter plume. Argon ions at energies from 320 to 1220 eV are studied. As expected, the directional

Atmospheric pressure plasma jets have great potential for the surface modification of polymers. In this work, the authors report on polystyrene etching by a radio frequency driven atmospheric pressure plasma jet with a focus on the role of H ⋅, O ⋅, and ⋅ OH radicals in this process. The absolute flux of H ⋅, O ⋅, and ⋅ OH radicals reaching the surface of the polymer was determined by a comsol multiphysics

While the basal plane of single-layer molybdenum disulphide (MoS2) is inert, attempts have been made to functionalize it chemically through the creation of defects and/or addition of dopants. With nanoparticles as dopants, the authors present density functional theory-based calculations of the hydrogenation of CO on a 31-atom, bilayer Au cluster supported on single-layer MoS2 (Au31/MoS2). Not surprisingly

Two-dimensional transition metal dichalcogenides (2D TMDs) is one of the promising materials for future electronics since they have, not only superior characteristics, but also a versatility that conventional materials do not have with a few nanometer thickness. One of the prerequisites for applying these materials to device fabrication is to deposit an ultrathin film below 10 nm with excellent uniformity

Layered cobalt oxides based on the hexagonal CoO2 layer, e.g., NaxCoO2 and [CoCa3O3]0.62CoO2 (or “Ca3Co4O9”), are promising thermoelectric materials. Here, the authors investigate the atomic layer deposition (ALD) of these materials in a thin-film form; this is not trivial, in particular, for the former compound, as both Na and Co are little challenged as components of ALD thin films. The authors employ

The authors report novel results toward optimizing the electrochemical performance of high vacuum deposited lithium-based all solid-state thin film microbatteries. This study investigated hermetic encapsulation, interfacial lithium formation processes, and the role of Li-blocking and Li-nucleating layers for improved Li-metal plating on copper anodes. Photoresist was found to be an effective temporary

This guide deals with methods to control surface charging during XPS analysis of insulating samples and approaches to extracting useful binding energy information. The guide summarizes the causes of surface charging, how to recognize when it occurs, approaches to minimize charge buildup, and methods used to adjust or correct XPS photoelectron binding energies when charge control systems are used. There

The properties of secondary particles for sputtering silicon with primary low-energy oxygen ions were investigated with dependence on the primary ion energy Eion and geometric parameters (ion incidence angle, polar emission angle, and scattering angle). The mass and energy distributions of the secondary particles were measured by energy-selective mass spectrometry. The experimental results were compared

Determination of molecular temperatures within low-temperature plasmas is critical to understanding the reactions that drive the chemistry of these systems and the mechanisms involved in plasma-surface interactions. Optical emission spectroscopy was employed to investigate gas-phase processes in H2 and CH4 inductively coupled plasma systems. Specifically, rotational temperatures (TR) have been determined

The use of inconsistent and incorrect terminology in scientific publications contributes to misunderstanding, confusion, and erroneous results in the scientific literature. This issue is of particular importance in x-ray photoelectron spectroscopy (XPS) that is in widespread use for many different purposes by scientists with diverse backgrounds. A set of surface analysis terminology, approved through

An essential element to realize lithium-ion microbatteries is an effective and conformal thin film solid state electrolyte over irregular or porous structures with specific composition and controlled elemental spatial distribution. Atomic layer deposition is a surface reaction based and non-line-of-sight technique that can rationally design an optimal electrolyte material, including high conductivity

In this paper, the emerging role of ionic species in plasma assisted chemical deposition processes is discussed in detail for commemorating the Career of John Coburn, who studied the role of ionic species in plasma etching processes forty years ago. It is shown that, in both plasma enhanced chemical vapor deposition and plasma enhanced atomic layer deposition processes, plasma ions can play a major

In high power impulse magnetron sputtering (HiPIMS) operation, there are basically two goals: a high ionized flux fraction of the sputtered target material and a high deposition rate. In this work, it is demonstrated that the former always comes at the cost of the latter. This makes a choice necessary, referred to as the HiPIMS compromise. It is here proposed that this compromise is most easily made

The sideways (radial) deposition rate and ionized flux fraction in a high power impulse magnetron sputtering (HiPIMS) discharge are studied and compared to a dc magnetron sputtering (dcMS) discharge, while the magnetic field strength | B | and degree of balancing are varied. A significant deposition of the film forming material perpendicular to the target surface is observed for both sputter techniques

Nanolaminated aluminum oxide (Al2O3)/hafnium oxide (HfO2) thin films as well as single Al2O3 and HfO2 layers have been grown as gate dielectrics by the plasma enhanced atomic layer deposition technique on silicon carbide (4H-SiC) substrates. All the three dielectric films have been deposited at a temperature as low as 250 °C, with a total thickness of about 30 nm, and, in particular, the nanolaminated

Through-silicon vias (TSVs) are a critical technology for three-dimensional integrated circuit technology. These through-substrate interconnects allow electronic devices to be stacked vertically for a broad range of applications and performance improvements such as increased bandwidth, reduced signal delay, improved power management, and smaller form-factors. There are many interdependent processing

In the gate-recess formation process, normally-off operation is achieved by removing the barrier layer by dry etching to reduce the two-dimensional-electron-gas concentration under the gate electrode. An atomic-layer defect-free etching of GaN is thus indispensable to achieve high-frequency, high-power, and normally-off operation. More-precise atomic-layer defect-free GaN etching was investigated by

As part of a Special Issue in Honor of 30 years of the American Vacuum Society’s Nellie Yeoh Whetten Award, this Invited Perspective discusses results and trends from the authors’ and other published research on metal contacts to β-Ga2O3, (4H and 6H)-SiC, nanocrystalline diamond (NCD), and nanocrystalline thin films and single-crystalline nanoribbons of α-SnS. The paper is not a comprehensive review

The growth rate of an SiO2 film on various metal–oxide (M–O) underlayers by plasma-enhanced atomic layer deposition (ALD) using tris(dimethylamino)silane precursor and O2 plasma gas is systematically investigated, and the effect of the difference in the electronegativity of the M–O underlayer on the ALD-SiO2 growth mechanism is also discussed. All data for the ALD-SiO2 film thickness on HfO2, TiO2

In the following review, the authors describe how the kinetics of film growth can be controlled in innovative ways to achieve the deposition of conformal, superconformal, area-selective, and ultrasmooth films by low-temperature CVD. Illustrative experimental data and kinetic models are given for the growth of a variety of materials, including transition metals, metal oxides, and metal diborides. Key

The effects of low-energy (<15 eV) high-flux O2+ ion bombardment on the properties of Al2O3 films deposited on 3D nanostructures by plasma-enhanced atomic layer deposition (PE-ALD) were investigated. High-dose O2+ ion bombardment (>1017 cm−2 cycle−1) during the oxidation steps caused interfacial mixing, and AlSiOx films with abrupt interfaces were formed on Si surfaces. Interfacially mixed AlSiOx films

Nanoscale spectroscopy and imaging, a hybrid technique that combines a scanning probe microscope (SPM) with spectroscopy, can provide nanoscale topographical, spectral, and chemical information of a sample. In recent years, developments in nanofabrication technology have dramatically advanced the field of nanospectroscopy for applications in various fields including nanoscale materials, electronics

A study of plasma polymerization of cyclopropylamine in a low-pressure cylindrical magnetron reactor is presented. Both experimental and numerical approaches are used to investigate thin film growth mechanisms and polymer film properties depending on the magnetic field strength. Combining both approaches enables the consistency of the numerical model to be checked while acquiring data for understanding

Monitoring vacuum ultraviolet (UV/VUV) emission in plasma systems is challenging as it requires specialized diagnostic systems or sensors to be compatible with these devices. This study addresses different reactor configurations and plasma chemistries with various levels of UV emission and their effects on a known set of polymers. First, the effect of He plasma treatment of organic underlayer (NFC-1400)

Atomic layer etching (ALE) of Ga-polar GaN (0001) using a standard inductively coupled plasma-reactive ion etching system is achieved in this work. The sequential process is using Cl2 to modify the surface in the adsorption step. For the activation step, the authors compare two rare gas plasmas, namely, Ar and Kr, and show a much larger and well-defined ALE window for the latter. The ALE of GaN is

The definition of microstructural features from an image is a challenge, given the uncertainty of the feature edges and the inherent user bias required in defining what is a feature. This challenge is particularly evident in atom probe tomography (APT), which captures tens of millions of atoms with their three-dimensional (3D) atomic position. Given the data uncertainty, issues with missing data, and

Atomic layer deposition of amorphous antimony sulfide (a-Sb2S3) is demonstrated with an alternating exposure of tris(dimethylamino)antimony (TDMASb) and hydrogen sulfide (H2S) at 150 °C in a custom-built viscous flow reactor. Growth mechanism and deposition chemistry are investigated by in situ quartz crystal microbalance and in situ Fourier Transform Infrared spectroscopy. Reaction hypothesis facilitating

Plasma is found almost everywhere in the universe. Yet most people are not conscious of its presence, nor the role it plays in creating the electronic devices in our everyday lives. Virtually every semiconductor chip has been touched by plasma, which is used in nearly half of all semiconductor manufacturing steps today. These chips power our mobile phones, computers, automobiles, and are vital for

Organic materials provide a very small thermal budget for any postfabrication treatment or for a subsequent layer in a device fabrication. This demand for the low-temperature process has driven the focus of this study to obtain atomic layer deposited oxide layer at a low temperature suitable for a buffer layer in perovskite solar cells. The buffer layer will assist in blocking holes, effectively extract

The ability to harness the processes by which complex tissues arise during embryonic development would improve the ability to engineer complex tissuelike constructs in vitro—a longstanding goal of tissue engineering and regenerative medicine. In embryos, uniform populations of stem cells are exposed to spatial gradients of diffusible extracellular signaling proteins, known as morphogens. Varying levels

Repeatability and reproducibility in surface analysis in the semiconductor industry are key for supporting efficient process development and high volume manufacturing (HVM). Long-term repeatability is critically important when comparing to historical data, while reproducibility is required to support technology transfers when HVM of specific devices is to be carried out at multiple sites. This, however

Nanocrystalline HfOx films were synthesized by an atomic layer deposition method using Hf[N(CH3)C2H5]4 as the metal precursor and La(NO3)3·6H2O solution as the oxidant. La(NO3)3·6H2O solution played the role of both oxidant and catalyst, catalytic oxidant, where the La element in the deposited HfOx films was under the detection limit. The introduction of La(NO3)3·6H2O solution instead of H2O effectively

Paraffin wax is currently used as an antirelaxation coating in alkali metal vapor cells since it prevents spin depolarization of alkali atoms. However, the performance of paraffin decreases rapidly above 80  °C due to degradation; thus, the inability to operate at higher temperatures motivates a search for alternatives. Here, the authors use first-principles density functional theory to study rubidium

The geologic profile of the western United States lends itself to naturally elevated levels of arsenic and uranium in the groundwater and can be aggravated by mining. The Navajo Nation, located in the American Southwest, is the largest contiguous Native American Nation and has over a 100-year legacy of hard rock mining. Concentrations of uranium and arsenic above drinking water standards in unregulated

High-quality Pt thin films are prepared by atomic layer deposition (ALD) using metal-organic precursors dimethyl-(N,N-dimethyl-3-butene-1-amine-N) platinum (C8H19NPt) and with diluted molecular oxygen (O2) as a reactant. The films are grown at a relatively low temperature of 225 °C on a thermally grown SiO2 substrate, and the process shows all the necessary qualities of an ideal ALD such as self-limiting

X-ray photoelectron spectroscopy (XPS) has become a standard tool for the study of catalytic materials over the last two decades, and with the increasing popularity of turnkey XPS systems, the analysis of these types of materials is open to an even wider audience. However, increased accessibility leads to an increase in the number of new or inexperienced practitioners, leading to erroneous data collection

This perspective explores the complexity of nitrogen chemistry and its interpretation from high-resolution x-ray photoelectron spectra by examining metal-nitrogen-doped carbon systems used in many technological applications. Current understanding of factors contributing to nitrogen 1s photoelectron spectroscopic signature is reviewed, and limitations on assigning precise chemistries to individual spectral

Film crystallinity is one of the key factors determining the resistivity of thin conductive nitride films. In the process of plasma enhanced atomic layer deposition (PEALD), the film crystallinity can be significantly improved by the ion bombardment effect taking place at a low pressure. At a low plasma pressure, ion bombardment supplies additional energy for adatom rearrangement and ligand desorption

Using CH3F/O2/He based chemistries in high density plasmas for silicon nitride spacer etching, loss of silicon in active source/drain regions of CMOS transistors can be observed. Minimizing the so-called silicon recess during nitride spacer etching is extremely difficult to achieve but mandatory since it directly impacts the device performance. In this work, the authors investigated the benefits of

Surfactant-templated porous organosilicate glass low-k films have been deposited by using a tetraethoxysilane (TEOS) and methyltriethoxysilane (MTEOS) mixture with different ratios and Brij® 30 surfactant. The deposited films contain different concentrations of terminal methyl groups that are proportional to the MTEOS concentration. Increasing the methyl group concentration by changing the TEOS/MTEOS

Metal oxide semiconductor capacitors that incorporate tantalum pentoxide (Ta2O5) thin films as dielectric were fabricated via the atomic layer deposition (ALD) technique and characterized through TEM, XPS, C–V, and I–V measurements. TEM analysis revealed the amorphous phase of Ta2O5 films and the existence of an ultrathin SiOx layer in the Ta2O5/p-Si interface, also evidenced by XPS spectra. XPS analysis

This work demonstrates the impact of the contact interface between barrier films and adhesives on the side permeation of moisture into packaged devices. When barrier films are brought into contact with the adhesive layer during indirect encapsulation, permeation along defects at this interface can occur due to the imperfect nature of contact, resulting in the formation of pores. The connected network

Atomic layer deposition (ALD) offers a viable route for the growth of thin and conformal films over 3D topographies and is becoming attractive as a method to grow films thin enough, and with sufficient dielectric constants (k), for the fabrication of next-generation dynamic random memories. The authors used ALD to grow thin (≤15 nm) BaxSr1 − xTiO3 (BST) films that are epitaxially integrated to SrTiO3

The unique flexible and piezoelectric properties of polyvinylidene fluoride (PVDF) films would allow for new applications for integrated bioelectronic devices. The use of these films has been precluded by the difficulty in machining them into small, discrete features without damaging the properties of the material. The etching of piezoelectric PVDF by means of a 193 nm excimer laser is explored and

The fabrication of Si0.7Ge0.3 sub-10 nm nanochannels in gate-all-around devices requires a highly selective Si isotropic etching process. The etching of Si selectively to Si0.7Ge0.3 with CF4/N2/O2 downstream plasma has been investigated using various morphological and surface characterization techniques. Conditions such as 400 W microwave power, 700 mTorr pressure, 25 °C chuck temperature, and 22%

In this work, the authors explore the impact that thermodynamic fluctuations have on the spontaneous appearance of defects during area selective deposition on patterned surfaces that are fully covered by adsorbates under local thermodynamic equilibrium, such as self-assembled monolayers. By using a simple lattice gas model for the adsorbed monolayer, the authors were able to track the spontaneous formation

Lithium intercalation compounds represent a class of technologically relevant nanoparticles that have revolutionized energy storage, namely, in their practical application as cathode materials used in rechargeable lithium ion batteries. An important class of such materials is the lithium metal oxides with the form LiMO2, where M represents Fe, Mn, Co, or Ni. The demand for these materials has led to

This guide briefly summarizes issues and considerations important for the use of x-ray photoelectron spectroscopy (XPS) for characterizing nanoparticles, which are important in many areas of science and technology. Because the surfaces play a major role in determining nanoparticle behaviors, XPS is an increasingly useful tool for understanding their properties, including addressing variations and nonreproducibility

The early work of John Coburn and Harold Winters revealed a synergistic effect in ion-enhanced Si etching by the concurrent irradiation of Ar+ and XeF2. This finding provided an important foundation for the development of plasma dry etching processes. The experimental results of Coburn and Winters also found effects that are useful for the development of atomic layer etching (ALE) processes characterized

A material etching system was developed by combining beam electron injection from a direct current hollow cathode (HC) electron source with the downstream reactive environment of a remote CF4/O2 low temperature plasma. The energy of the injected beam electrons is controlled using an acceleration electrode biased positively relative to the HC argon discharge. For an acceleration voltage greater than

A new industrial approach for the production of CuInSe2 (CISe) absorber layers in a roll-to-roll process is described. This process is used by Sunplugged GmbH and combines magnetron sputtering with thermal coevaporation. A CISe-based device with a conversion efficiency of more than 10% has been fabricated from absorbers grown on polyimide at low temperature. The characteristic properties of a copper-poor

Laser refractometers are approaching accuracy levels where gas pressures in the range 1 Pa < p < 1 MPa inferred by measurements of gas refractivity at a known temperature will be competitive with the best existing pressure standards and sensors. Here, the authors develop the relationship between pressure and refractivity p = c 1 ⋅ ( n - 1 ) + c 2 ⋅ ( n - 1 ) 2 + c 3 ⋅ ( n - 1 ) 3 + ⋯ , via measurement

The brain is composed of complex neuronal networks that interact on spatial and temporal scales that span several orders of magnitude. Uncovering how this circuitry gives rise to multifaceted phenomena such as perception, memory, and behavior remains one of the grand challenges in science today. A wide range of investigative methods have been developed to delve deeper into the inner workings of the

The mechanism of thermal dry etching of cobalt films is discussed for a thermal process utilizing sequential exposures to chlorine gas and a diketone [either 1,1,1,5,5,5-hexafluoro-2,4-pentanedione (hexafluoroacetylacetone, hfacH) or 2,4-pentanedione (acetylacetone, acacH)]. The process can be optimized experimentally to approach atomic layer etching (ALE); a sequential exposure to Cl2 and hfacH dry

Over the past three decades, the widespread utility and applicability of X-ray photoelectron spectroscopy (XPS) in research and applications has made it the most popular and widely used method of surface analysis. Associated with this increased use has been an increase in the number of new or inexperienced users which has led to erroneous uses and misapplications of the method. This article is the

Analysis of the surface of thin Irganox 1010 films before and after sputtering with an argon gas-cluster ion beam was performed with AFM and XPS to determine the effect that Zalar rotation has on the chemistry and morphology of the surface. The analysis is based on the change in roughness of the surface by comparing the same location on the surface before and after sputtering. The ion beam used was

Recent advances in preservation of the morphology of ZnO nanostructures during dye sensitization required the use of a two-step preparation procedure. The first step was the key for preserving ZnO materials morphology. It required exposing clean ZnO nanostructures to a gas-phase prop-2-ynoic acid (propiolic acid) in vacuum. This step resulted in the formation of a robust and stable surface-bound carboxylate

Ultra-high vacuum systems must often be constructed of materials with ultra-low outgassing rates to achieve pressure of 10-6 Pa and below. Any component placed into the ultra-high vacuum system must also be constructed of materials with ultra-low outgassing rates. Baking stainless steel vacuum components to a temperature range of 400 °C to 450 °C while under vacuum is an effective method to reduce

Pd(111) thin films, ∼245 nm thick, are deposited on Al2O3(0001) substrates at ≈0.5Tm, where Tm is the Pd melting point, by ultrahigh vacuum dc magnetron sputtering of Pd target in pure Ar discharges. Auger electron spectra and low-energy electron diffraction patterns acquired in situ from the as-deposited samples reveal that the surfaces are compositionally pure 111-oriented Pd. Double-axis x-ray diffraction

This article represents a recommended practice for the calibration of ionization gauges using the comparison method. In this method, ionization gauges are compared to a working standard that has an SI traceable calibration. The ionization gauge is either of the hot-cathode ionization type or the cold-cathode ionization type. Details of the calibration apparatus, the principle of operation of the gauges