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Nanometer-sized particles of the solid acid electrolyte material CsH2PO4 have been prepared by electrospray synthesis. Using a differential mobility analyzer to provide real-time particle-size information, the role of electrospray parameters, such as precursor solution composition, surface tension, and conductivity, sheath gas temperature and flow rate, and solution flow rate, were evaluated. The results are compared with particle sizes calculated using well-established scaling laws. The much smaller sizes of the detected particles in comparison to the sizes expected from the predicted initial droplet sizes suggests that droplets undergo fission along the path toward deposition. In flight fission events may also explain the observed counterintuitive result that aerosol particle size decreases with increasing solute concentration. The in situ feedback provided by this system enabled rapid identification of solution and process parameters that result in mean particle sizes of ∼15 nm, substantially smaller than any prior results. Copyright © 2023 American Association for Aerosol Research [ABSTRACT FROM AUTHOR]

A study was conducted to analyze the functions of surface currents on pattern-dependent charging. Monte Carlo simulations were carried out on pattern-dependent charging during etching in high-density plasmas supporting a maximum sustainable surface electric field. Two possible mechanisms for electron conduction along the SiO2 surface were also determined in the study. Results indicated pattern-dependent charging as a major reason for notching.

Monte Carlo method simulations were conducted for pattern-dependent charging during interlevel dielectric (ILD) deposition in high-density plasmas. Findings show that the initial conformality of the ILD film has a significant role in metal line charging up and the subsequent degradation to the buried gate oxide to which the metal line is connected. Results indicate that charging can be reduced by depositing a more conformal ILD film around the metal line and/or by increasing the capability of the film surface to dissipate charge.

Feature-scale charging simulations were conducted on high-density plasmas subjected to gate electrode overetching. Results indicate that insulating mask thickness significantly influences charging damage. Damaging tunneling currents through underlying oxides can be avoided by employing thinner hard masks which increase the electron irradiance of sidewalls' conductive components.

Submicron pattern transfers are spurring the development of new, low pressure, high charge density plasma reactors, and are controlled by an unprecedented demand for uniformity, throughput, anisotropy and damage control. An improved ion flux and energy control in these systems is provided by water biasing independent of plasma production, so that selectivity can be optimized and damage can be minimized. An inherent property of such discharges is the generation of excited, metastable ionic states.

Extending the principle of operation of hollow cathode microdischarges to a tube geometry has allowed the formation of stable, high-pressure plasma microjets in a variety of gases including Ar, He, and H[sub 2]. Direct current discharges are ignited between stainless steel capillary tubes (d = 178 µm) which are operated as the cathode and a metal grid or plate that serves as the anode. Argon plasma microjets can be sustained in ambient air with plasma voltages as low as 260 V for cathode-anode gaps of 0.5 mm. At larger operating voltage, this gap can be extended up to several millimeters. Using a heated molybdenum substrate as the anode, plasma microjets in CH[sub 4]/H[sub 2] mixtures have been used to deposit diamond crystals and polycrystalline films. Micro-Raman spectroscopy of these films shows mainly sp³ carbon content with slight shifting of the diamond peak due to internal stresses. Optical emission spectroscopy of the discharges used in the diamond growth experiments confirms the presence of atomic hydrogen and CH radicals. [ABSTRACT FROM AUTHOR]

The Eley-Rideal abstraction involving [F.sup.+] projectiles and fluorinated Ag and Si surfaces occurring at high impact energies that result in hyperthermal [F.sub.2.sup.-] ions leaving the surface at energies of tens of electron volts is described. The results from energy analysis of the [F.sub.2.sup.-] products as well as bombardment of externally fluorinated surfaces with [super 22][Ne.sup.+] rather than [F.sup.+] showed that [F.sup.+] projectiles are required for fast-[F.sub.2.sup.-] formation.

Studies by Monte Carlo simulations the effect of aspect ratio on charge buildup in trenches during plasma etching of polysilicon-on-insulator structures. Description of plasma conditions and microstructure; Simulation of microstructure charging; Simulation of sidewall profile evolution.

Presents a study which optimized hydrogen plasma operating conditions for surface passivation of native-oxide-contaminated gallium arsenide. Experimental details; Utilization of real-time photoluminescence of the operating conditions; Conclusion.

When patterned surfaces are exposed to plasmas, the directionality difference between ions and electrons causes differential charging of the pattern. Potential contour maps, generated by Monte Carlo simulations of charging in mixed conductor-insulator structures, illustrate where charging occurs and how it becomes more aggravated as the number of features in the pattern increases (a feature multiplicity effect). Index Terms - Charging, damage, plasmas, simulations.