A5028052021- Magnetic confinement fusion research
- Semiconductor materials and devices
- Plasma Diagnostics and Applications
- Copper Interconnects and Reliability
- Ionosphere and magnetosphere dynamics
- Particle accelerators and beam dynamics
- Solar and Space Plasma Dynamics
- Metal and Thin Film Mechanics
- Integrated Circuits and Semiconductor Failure Analysis
- Thin-Film Transistor Technologies
- Astro and Planetary Science
- Ion-surface interactions and analysis
- Advanced Surface Polishing Techniques
- Superconducting Materials and Applications
- Laser-induced spectroscopy and plasma
- Electron and X-Ray Spectroscopy Techniques
- Electrostatic Discharge in Electronics
- Laser-Plasma Interactions and Diagnostics
- Vacuum and Plasma Arcs
- Dust and Plasma Wave Phenomena
- Electrohydrodynamics and Fluid Dynamics
- Silicon and Solar Cell Technologies
- Photonic and Optical Devices
- Surface Modification and Superhydrophobicity
- Spacecraft and Cryogenic Technologies
University of Wisconsin–Madison
2013-2024
Madison Area Technical College
2017
Stanford University
2014-2016
KLA (United States)
2016
National Synchrotron Radiation Research Center
2016
GlobalFoundries (United States)
2016
Intel (United States)
2015
IMEC
2015
KU Leuven
2015
Applied Materials (United States)
2014
In this work, experimental measurements of the electronic band gap low-k organosilicate dielectrics will be presented and discussed. The measurement bandgap energies organosilicates made by examining onset inelastic energy loss in core-level atomic spectra using X-ray photoelectron spectroscopy. This serves as a reference point from which many other facets material can understood, such location presence defect states bulk or at interface. A comparison with techniques reported literature is presented.
HSX is a quasi-helically symmetric (QHS) stellarator currently under construction at the Torsatron-Stellarator Laboratory of University Wisconsin - Madison. This device unique in its magnetic design that field spectrum possesses only single dominant (helical) component. avoids large direct orbit losses and low-collisionality neoclassical associated with conventional stellarators. The restoration symmetry to confining makes confinement this analogous an axisymmetric q = 1/3 tokamak.The magnet...
Electron-density and electron energy distribution functions (EEDFs) are measured in a 20-cm-diam by 14-cm-long cylindrical, inductively coupled plasma source driven fields from planar, spiral coil at 13.6 MHz. Radio-frequency (rf) -filtered Langmuir probes used to obtain spatial profiles of population characteristics argon powers pressures interest for etching plasma-assisted deposition (1–100 mT). Electron densities range 1010 1012 cm3 with 100–500 W rf power peak on axis the center...
Protein three-dimensional structure dynamically changes in solution depending on the presence of ligands and interacting proteins. Methods for detecting these protein conformation include 'protein footprinting,' using mass spectrometry. We describe herein a new technique, PLIMB (Plasma Induced Modification Biomolecules), that generates µs bursts hydroxyl radicals from water, to measure via altered solvent accessibility amino acid side chains. was first benchmarked with model compounds, then...
This paper presents an in-depth overview of the application and impact UV/VUV light in advanced interconnect technology. UV BEOL historically was mainly motivated by need to remove organic porogen generate porosity organosilicate (OSG) low-k films. Porosity lowered film's dielectric constant, k, which enables one reduce wiring capacitance contribution RC signal delay integrated circuits. The UV-based film curing (λ > 200 nm) proved superior thermal annealing electron beam curing. VUV...
Abstract The emergence of memristive behavior in amorphous–crystalline 2D oxide heterostructures, which are synthesized by atomic layer deposition (ALD) a few‐nanometer amorphous Al 2 O 3 layers onto atomically thin single‐crystalline ZnO nanosheets, is demonstrated. conduction mechanism identified based on classic oxygen vacancy conductive channels. nanosheets provide host for vacancies, while the facilitates generation and stabilization vacancies. high‐resistance state follows...
The present and potential applications of plasma-aided manufacturing are discussed described. Plasma-aided is used for producing new materials with unusual superior properties, developing chemical compounds processes, machining, altering refining surfaces. has direct to semiconductor fabrication, synthesis, welding, lighting, polymers, anticorrosion coatings, machine tools, metallurgy, electrical electronics devices, hazardous waste removal, high-performance ceramics, many other items in...
The entry problem in plane laminar magnetohydrodynamic flow is solved numerically for various values of the pertinent parameters describing flow. channel configuration a parallel-plate which has Hartmann profile its fully developed velocity equations are placed finite difference form to enable essential nonlinearities principal be used solution problem. Velocity, temperature, and pressure curves presented from results computational work.
Plasmas, known to emit high levels of vacuum ultraviolet (VUV) radiation, are used in the semiconductor industry for processing low-k organosilicate glass (SiCOH) dielectric device structures. VUV irradiation induces photoconduction, photoemission, and photoinjection. These effects generate trapped charges within film, which can degrade electrical properties dielectric. The amount charge accumulation dielectrics depends on factors that affect Changes photo intrinsic conductivities SiCOH also...
In this work, core-level X-ray photoelectron spectroscopy was utilized to determine the surface bandgap for various porous and non-porous low-k a-SiCOH dielectrics before after ion sputtering. By examining onset of inelastic energy loss in O 1s spectra, gap narrowing universally found Ar+ sputtered dielectrics. The reduction ranges from 1.3 2.2 eV depending on film composition. We show that these is caused by development valence-band tail as evidenced presence additional electronic states...
A Mach probe is used to measure poloidal and toroidal flows induced by a biased electrode in IMS. theories are reviewed classified as either magnetized or unmagnetized. simple geometric model of the IMS shows that variation effective area function orientation with respect magnetic field 20%–25%, predicting be only slightly magnetized. Measurements total ion saturation current collected probe, angle varied, demonstrate this level magnetization at low neutral pressure large minor radius, while...
Damage induced in low-k porous organosilicate glass (SiCOH) dielectric films by exposure to an electron cyclotron resonance (ECR) plasma was investigated. The effects of charged-particle bombardment and vacuum ultraviolet radiation were separated. Flux measurements showed that the ECR has a greater photon flux (VUV) range than UV range. measured examining surface potential capacitance-voltage characteristics after exposure. It found during argon processing, 75% charge accumulation comes from...
Time-dependent dielectric breakdown (TDDB) is a major concern for low-k organosilicate dielectrics. To examine the effect of plasma exposure on TDDB degradation, time-to-breakdown measurements were made porous SiCOH before and after to plasma. A capillary-array window was used separate charged particle vacuum ultraviolet (VUV) photon bombardment. Samples exposed VUV photons, combination photons ion bombardment exhibited significant degradation in time. The samples showed more time comparison alone.
Water uptake in porous low-k dielectrics has become a significant challenge for both back-end-of-line integration and circuit reliability. The influence of absorbed water on the mechanical properties plasma-enhanced chemical-vapor-deposited organosilicate glasses (SiCOH) was investigated with nanoindentation. roles physisorbed (α-bonded) chemisorbed (β-bonded) were examined separately through annealing at different temperatures. Nanoindentation measurements performed dehydrated glass during...
The effects of plasma exposure and vacuum-ultraviolet (VUV) irradiation on the mechanical properties low-k porous organosilicate glass (SiCOH) dielectric films were investigated. Nanoindentation measurements made SiCOH before after to an electron-cyclotron-resonance or a monochromatic synchrotron VUV beam, determine changes film hardness, elastic modulus, crack threshold due these exposures. This permits ion bombardment photon be analyzed separately. role energetic ions was examined with...
This work investigates the vacuum ultraviolet (VUV) emission from various feed gases producing plasmas in an electron cyclotron resonance etcher. Absolute measurements of plasma VUV at typical pressures for processing between 0.5 and 5 mTorr, microwave powers 700 1300 W, show levels irradiance wafer position order tenths mW/cm2 integrated photon fluxes 1014 photons/cm2 s range. The reported level is sufficient to induce radiation damage metal–oxide–semiconductor devices form flatband voltage...
Global excitation of Alfv\'en waves in the Proto-Cleo $l=3$ stellarator was accomplished by exciting a helical winding corresponding to $q=3$ rational surface with pulsed, high-power rf source. A doubling both electron and ion temperatures observed, slight increase ratio without heating occurred at predicted resonance locations. Enhanced loss also during heating, 2.5-kHz oscillations observable microwave interferometer signal after heating.
Vacuum ultraviolet (VUV) spectroscopy is used to determine the valence-band structure and location of defect states within bandgap porous organosilicate (SiCOH) dielectrics both before after VUV UV irradiation. SiCOH have energies about 9 eV. In addition, positive charge trapped by located 1 eV above top edge. These can be populated or depopulated with electrons during irradiation, respectively. This verified measuring magnitude polarity irradiation using two techniques: (i) capacitance vs...
A cylindrical microwave cavity containing a concentric plasma column can be resonated in an infinite number of electromagnetic wave modes. The resonances all shift upward towards coaxial modes as the electron density is increased if collisions are neglected. characteristic eigenvalue equation for including collisional effects derived and typical graphs fundamental presented. solutions explained on basis coupled-mode theory. empty mode (infinite density) which originally overcoupled, uncouple...
During plasma processing of semiconductors, ultraviolet (UV) and vacuum (VUV) radiation are present, but their effects can be difficult to separate from those due charged particles incident on the wafer. The contribution VUV photon irradiation gate-oxide damage, damage dielectric materials in general, was examined using two measurement techniques that predict possibility damage. They (1) surface potential measurements (2) electrically erasable read-only memory transistors (CHARM-2 wafers)....
The Interchangeable Module Stellarator (IMS) is a new toroidal stellarator-type device under design and construction at the University of Wisconsin Torsatron/Stellarator Laboratory. A strategy for constructing stellarator magnetic fields from discrete modular coils has been developed, utilizing orthogonal coordinates. Application this method resulted in coil system (IMS), whose structure closely approximates that Proto-Cleo Q = 3 7-field period (i. e., rotational transform, shear, flux volume, etc.).