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Patients with atrial fibrillation (AF) have an increased stroke risk. This can be managed by oral anticoagulation (OAC) but a substantial number of patients are ineligible. The left atrial appendage (LAA) is the predominant thrombus source in AF, thus LAA management may reduce stroke risk. We

For the feature size scaling down to tens of nanometers, the top-down approaches are getting more severe because the extremely ultra-violet (EUV) technique, the high-index fluid-based immersion ArF lithography, and the double patterning technology (DPT) under development may be cover one or two generations. An alternative technology to extend lithography patterning beyond current resolution limits is to combine the top-down lithography and bottom-up assembly. In this paper, an directed self-assembly lithography process of ''bottom-up'' block copolymer self-assembly, is modeled and simulated in molecular-scale. Impacts of block polymer components on pattern formation are analyzed and discussed.

t SEUDOMYXOMA PERITONEI (PMP) is a rare disease process characterized by copious mucus accumulation in he abdomen and pelvis.1 In most cases, PMP is believed to riginate from an appendiceal tumor and is often considered a borderline malignancy” because of its progressive nature, ropensity for regional spread, and tendency to recur without efinitive surgical treatment.1 Tumor cells and associated muin redistribute within the peritoneal cavity in a pattern that oincides with the normal flow and resorption of peritoneal uid.2 Without treatment, the disease is fatal as the mucinous umor overwhelms the available space within the abdomen, nhibiting the normal nutritional function of the digestive sysem1 and exerting upward pressure on the diaphragm that ompromises pulmonary function. Despite the aggressive pread of the disease within the peritoneal cavity, lymphatic nd hematogenous metastasis of PMP is rare.1 However, exension of disease beyond the abdomen to the pleural cavity has een reported.3-7 Most of these cases are believed to have arisen rom direct extension of the tumor cells secondary to surgical rauma, pleuroperitoneal communications, or direct tumor inasion of the diaphragm.3-7 The median survival for patients with PMP is 6 years with ggressive treatment.1 Current treatment consists of cytoreducive surgery (CRS) with intraoperative hyperthermic intraperioneal chemotherapy for peritoneal disease and intraoperative yperthermic intrathoracic chemotherapy (HITHOC) for disase involving the pleural cavity.1,6 Secondary to the use of igh-dose chemotherapy, postoperative side effects include oncardiogenic pulmonary edema, interstitial pneumonitis, leural effusions, cardiomyopathy, leucopenia, and thrombocyopenia.8-10 In addition, use of hyperthermia may cause scald njury to tissues within the perfused cavity or induce systemic ever, complications of which include myocardial ischemia, ulmonary edema,11 ventilator-induced acute lung injury,12 eurocognitive dysfunction,13 and nerve damage.14 Combining CRS and HITHOC to treat pleural disseminaion resulting from various malignancies is in its infancy, nd to date, there have only been a handful of studies valuating its feasibility and efficacy. Moreover, little is nown about the anesthetic challenges in patients undergong this multimodality treatment, and there have been no ublished reports addressing anesthetic strategies. Thereore, the anesthetic management of a patient undergoing RS and HITHOC for the treatment of pleural dissemination esulting from PMP is presented.

Recent advances in the design of multichannel ellipsometers based on rotating-element principles have significantly increased their power for applications involving in-situ, real-time analysis of thin films and surfaces. These advances include: (i) extensions in the upper spectral limit beyond the typical value of 4.5 eV, and (ii) increases in the number of extracted parameters beyond the usual two, namely the ellipsometric angles (ψ, Δ). An extended spectral range is enabled, for example, by use of a tandem light source configuration and a grating spectrograph having two stages of order-sorting filters mounted over the window of the linear array detector. With an upper spectral limit of 6.5 eV, such ellipsometers are particularly useful in growth analysis for wide band gap thin films. The larger parameter set is enabled by use of dual or single rotating compensators for polarization state modulation and/or analysis, replacing the traditional rotating polarizer. For the single rotating-compensator instrument in the PSCrA configuration, one can extract the Stokes vector of the reflected beam, and thus its degree of polarization. This in turn can provide information on sample thickness variations over the beam cross-section and can suppress the effects of multiply-scattered light so that non-uniform and macroscopically rough surfaces can be analyzed. For the dual rotating compensator in the PCr1SCr2A configuration, one can extract the entire Mueller matrix of the sample and thus the characteristics of anisotropic surfaces and thin films. Applications of these advances include studies of thickness evolution of the phase for boron nitride and silicon film growth, and the nature and origin of surface-induced optical anisotropy of (110) silicon.

A rotating-compensator multichannel ellipsometer has been developed for ultraviolet-extended real time operation over the spectral range from 1.5 to 6.5 eV. The enhancements to the conventional rotating-compensator multichannel instrument to obtain this wide range include: (i) a tandem D 2 -Xe source, (ii) MgF 2 optical elements, (iii) a grating spectrograph blazed at 250 nm and (iv) two stages of order sorting filters internal to the spectrograph. The key in this effort is to maintain a flat spectral distribution over as wide a spectral range as possible in order to reduce spectrograph stray light, which is the primary error that limits the range of multichannel instruments. In this paper, new calibration and data reduction methods are described that determine the polarizer and analyzer angular offsets, and the rotating-compensator azimuthal phase angle and retardance spectra with the highest possible accuracy while minimizing instrument-related errors.

The Mueller matrices describing oblique incidence reflection and normal incidence transmission have been measured for sculptured thin films (STFs) by glancing angle deposition with simultaneous substrate rotation. In data reduction, the 15 parameters of the (1,1)-normalized real Mueller matrix are converted to the six parameters of the (2,2)-normalized complex Jones matrix. Two computational methods yield excellent agreement in the real and imaginary parts of the complex amplitude ratios ρps and ρsp obtained in reflection (or τps and τsp obtained in transmission). Multilayer optical analysis has been developed that employs step-wise variations of the principal axis Euler angles, associated with the local uniaxial structure in successive sublayers, in order to simulate variations in the column orientation with depth into the film. Such analysis has elucidated the Bragg resonance characteristics exhibited by the optical rotation of chiral STFs.

We have measured spectra from ∼2 to 5 eV in all 15 elements of the normalized Mueller matrix for (110) Si at an angle of incidence of θ a ∼70°, as an initial demanding performance test of a novel dual rotating-compensator multichannel ellipsometer. The Mueller matrix spectra, deduced from 36 waveform integrals collected over a single optical cycle of 0.25 s, can be analyzed to extract the bulk isotropic dielectric function e b = e 1b - ie 2b and the surface-induced dielectric function anisotropy Δe s = Δe 1s -iΔe 2s . Starting from the 15 Mueller matrix elements, six sample parameters are determined, namely the real and imaginary parts of the complex amplitude reflection ratios ρ pp , ρ ps , and ρ sp . The surface-induced anisotropic response (Δe s ) d = [e s (110)-e s (001)]d is deduced from an average of four independent spectra, two in ρ sp and two in ρ ps = - ρ sp using the first order term in d/λ from an expansion of the partial transfer matrix. Here d is the surface anisotropic layer thickness and λ is the vacuum wavelength. Because both the real and imaginary parts of (Δe s )d are now accessible, the results can be fit using a Kramers-Kronig (K-K) consistent oscillator model. The key advantage of the newly-developed instrument is the ability to perform spectroscopic measurements in real time that simultaneously provide bulk isotropic and surface- or interface-induced anisotropic optical responses.

A multichannel ellipsometer in the dual rotating-compensator configuration has been designed and constructed for applications in real time Mueller matrix ellipsometry (approx. 2–5 eV) of anisotropic surfaces and films. The sequence of optical elements for this instrument is denoted PC 1r ( ω 1 ) SC 2r ( ω 2 ) A , where P , S , and A represent the polarizer, sample, and analyzer. C 1r ( ω 1 ) and C 2r ( ω 2 ) represent two MgF 2 biplate compensators that rotate at frequencies of ω 1 /2 π =10 Hz and ω 2 /2 π =6 Hz, synchronized for a ratio ω 1 : ω 2 of 5:3. Spectra in the 16 Mueller matrix elements of a transmitting or reflecting sample can be established from the 25 non-zero Fourier coefficients of the irradiance waveform acquired in a single 0.25 s optical cycle . Initial high speed Mueller matrix measurements have been performed on weakly anisotropic samples that push the instrument to its precision/accuracy limits. These include the (110) Si surface with maximum cross-polarization ellipsometric angles of ψ ps ∼0.1° and nanostructured thin films with maximum ψ ps ∼1°.

Photodeposition of thin polymer (PDAMNA) films from diacetylene monomer (DAMNA) solutions onto gold coated silica substrates with UV light was studied using the technique of in-situ real time spectroscopic ellipsometry. The dielectric function of PDAMNA was determined; and the thickness of the growing PDAMNA films over a 4 hour time interval was determined using a linear regression fit of the experimental data to a homogeneous four phase optical model. It was found that stirring the solution dramatically lowers the rate of film deposition, suggesting that convection can affect the attachment kinetics of the film to the substrate. Lastly, the morphology of the PDAMNA films was examined using non-contact mode atomic force microscopy.

Since the development and perfection of automatic ellipsometers, an effort that began nearly three decades ago, spectroscopic ellipsometry (SE) has increased in popularity as a non-destructive tool for characterizing the optical properties and layered structure of bulk solids and thin films. With the more recent development of multichannel ellipsometers for high-speed spectral scanning, in situ real-time SE has emerged as a very powerful tool for characterizing the time evolution of the optical properties and layered structure of materials during preparation and processing. High-speed spectral scanning has also opened up the possibility of real-time monitoring and control for complex material systems that cannot be fully characterized using well-established real-time measurements at one (or a few) wavelength(s). In this review, we will first describe the most recent developments in multichannel, multiparameter SE, in which spectroscopic information is obtained in addition to the ellipsometric parameters (ψ, Δ). Then we will discuss recent applications of multichannel SE to amorphous semiconductor film growth in order to obtain material properties in complex multilayer and graded-layer device structures. In general in this review, the focus will be on recent examples of the characterization of complex optical systems of technological interest. Practical situations will be described in which the dielectric functions of films are deposition-dependent and evolve with thickness due to particle and grain size effects and intentional compositional gradients, and in which film growth occurs on rough surfaces, leading to optical models for film growth that require interface and surface roughness layers.

We describe applications of the rotating polarizer multichannel ellipsometer for three-parameter spectroscopy (1.4–4.1 eV), in which a full reflectance spectrum is acquired simultaneously with (ψ, Δ), all in a time as short as 16 ms. Because data acquisition requires no significant effort beyond that of spectroscopic ellipsometry, the challenge of three-parameter spectroscopy becomes one of utilizing the third parameter effectively. Here, we demonstrate its utility in measurements either vs. fixed analyzer angular setting A for instrument calibration or vs. time for kinetic studies of nucleating films. In calibration, accurate results for the polarizer phase and analyzer azimuth scale correction can be obtained from measurements of the average reflected irradiance vs. A in the sample measurement configuration, irrespective of the value of Δ for the surface. In the kinetic studies of thin-film nucleation, the reflectance spectrum provides a criterion that allows one to identify the correct thickness and thus extract the evolution of the dielectric function with thickness. This procedure is demonstrated for Ag thin-film nucleation by magnetron sputtering on Si substrates.

We have applied real-time spectroscopic ellipsometry to monitor the growth of highly uniform, nanocrystalline diamond films by microwave plasma-enhanced chemical vapour deposition. In this study, a unique multichannel instrument is employed to collect full ellipsometric spectra from 1.5 to 4.0 eV. Here we focus on two capabilities. First, we will describe a method to calibrate the true temperature of the top 200Aof the Si substrate under diamond growth conditions. Second, we describe the full microstructural evolution of the diamond films. The parameters derived include the time evolution of the void and optically absorbing, non-diamond (sp 2 ) carbon volume fractions in the film. In addition, the nuclei, bulk and surface roughness layer thicknesses during the nucleation, coalescence and bulk growth regimes are determined. These results reveal reproducible and remarkably internally consistent behaviour that provides new insights into the growth mechanisms for nanocrystalline diamond. We find that in the coalescence process, a large volume fraction of sp 2 carbon is trapped in the grain boundaries under all conditions of growth. After coalescence is complete, further generation of sp 2 carbon is impeded under optimum conditions.

We have exploited the unique capabilities of a rotating-polarizer multichannel spectroscopic ellipsometer in real time studies of the evolution of microstructure and optical functions for various thin film materials. With a 16 ms acquisition time for ∼50 point spectra from 1.3 to 4.3 eV, the precision of the ellipsometer is (0.04°, 0.12°) in (Ψ, Δ) for a Si surface at 2.5 eV. Real time investigations of aluminum prepared by physical vapor deposition and hydrogenated amorphous semiconductors prepared by plasma-enhanced chemical vapor deposition are highlighted here. We focus on capabilities that elude a real time discrete-wavelength approach. For aluminum, this includes determining (i) the optical functions of small Al particles (

We applied multichannel spectroscopic ellipsometry (SE) to study the kinetics of thin film modification by hydrogen in vacuum and electrochemical environments. In this paper, we focus on the hydrogenation of amorphous silicon films in vacuum by exposure to thermally generated atomic hydrogen. The method developed to analyze the real time SE data in this particular case is applicable to other processes, and results are also included for the coloration of WO3 by electrochemical incorporation of H. Because the ellipsometer can provide spectra in (ψ, Δ) from 1.5 to 4.5 eV in 16 ms, improved characterization of diffusion and reaction kinetics can result, in comparison with previous work at fixed photon energy.

Spectroscopic ellipsometry over the range 1.5–4.5 eV was applied as a real time probe of the processes occurring in the initial nucleation of thin film diamond by heated-filament assisted chemical vapor deposition. Using both untreated and diamond-polished c-Si substrates, as well as both carburized and uncarburized tungsten filaments, it was possible to separate and characterize competing phenomena, including the increase in surface temperature induced by filament ignition, the formation of carbide layers, contamination of the substrate by tungsten from the filament, annealing of diamond polishing damage, and, finally, diamond nucleation. An accurate measurement of the true temperature of the substrate surface averaged over the top 500 A can be obtained from the energy position of critical points in the c-Si band structure. For diamond deposition, we operated with an initial excess flow of CH4 to stimulate nucleation. We applied real time feedback and manual control to reduce the CH4 flow in the first monolayers of deposition. The thickness of diamond and an estimate of its nucleation density can be obtained from real time spectra, and the latter was in good agreement with that obtained from scanning electron microscopy.

A rotating polarizer multichannel ellipsometer was applied in spectroscopic (1.3–4.2 eV) investigations of thin films during deposition. In this review, two examples are selected which demonstrate real time spectroscopic ellipsometry. In the first, we compare results for amorphous silicon and germanium sputtered to approximately 50 A on native oxide-covered c-Si. For these films, the evolution of the effective optical properties with thickness is dominated by changes in void volume fraction and surface roughness which accompany nucleation and growth. Abrupt transitions from cluster to bulk film growth occur at total thicknesses of 10–15 A for materials deposited under optimum conditions of microstructural uniformity. In the second example, corresponding results for aluminum evaporated to opacity onto thermally oxidized c-Si are discussed. In this case, the evolution of the effective optical properties with thickness is strongly influenced by changes in the intrinsic aluminum dielectric function. In particular, we find that the relaxation time for the (200) parallel-band transition increases abruptly with thickness over the 55–60 A range. The enhanced scattering of electrons in the films less than 60 A thick may originate from a disordered or fine-grained film structure, and for thicknesses less than 55 A the (200) parallel-band feature in the aluminum dielectric function at 1.5 eV disappears.

Experimental procedures are described to enhance the accuracy of a novel rotating polarizer multichannel ellipsometer, designed to real-time spectroscopic studies of film growth and surfaces. For the fastest such instrument 128-point (ψ,Δ) spectra from 1.5 to 4.5 eV can be acquired in less than 10 ms. Ellipsometry places stringent demands on the photodiode-array-based detection system, as the irradiance incident on the separate pixels is waveform analyzed. A detailed characterization of the detection system is presented which provides the means to correct for stray light, image persistence, non-linearity, and integration errors. We also outline techniques for characterization of imperfections associated with the source and polarization optics. We present calibration and data reduction equations which have been derived to include source and polarization system imperfection parameters to first order.

A unique real time spectroscopic ellipsometer has been applied to determine the microstructure and optical properties of plasma enhanced CVD (PECVD) and sputtered amorphous semiconductors. With this instrument, the limitations of single wavelength ellipsometry have been overcome, and the dielectric functions and optical gap (corrected for surface effects) have been obtained from real time observations on films as thin as 20 A. A wealth of information on the microstructural evolution at the monolayer scale is also deduced; e.g. the mass thickness evolution, and the nucleation density and cluster thickness when nuclei make contact to form the first full-coverage monolayer. The coalescence process first noted in earlier single wavelength ellipsometry studies of optimum PECVD a-Si:H has also been completely quantified.

Real-time spectroscopic ellipsometry has been developed for comprehensive optical characterization of vacuum-deposited thin films and their interfaces. A rotating-polarizer ellipsometer with multichannel detection was used to collect spectra at 15s intervals (about every 15A) during ion beam deposition of hydrogenated amorphous carbon (a-C:H) thin films on tantalum substrates. Each of the spectra consists of 80 pairs of ellipsometric angles {ψ(hν), Δ(hν)}, from 1.65 to 4.00 eV. A linear regression technique is introduced to analyze over 100 such spectra and to deduce the real and imaginary parts of the a-C: H dielectric function {e1, e2} and the film thickness vs. time within a three-medium model (Ta/a-C:H/ambient). As a result, a measure of the optical gap has been deduced, representing the first such determination from real-time data. A four-medium model, including a substrate-film interfacial layer, accounts for a discrepancy between the spectroscopic data and the three-medium model in the initial stage of a-C:H growth. An estimate of the thickness and {e1, e2} for the interface layer, from .12 spectra obtained in the first 180A of a-C:H growth on Ar+-sputter-cleaned tantalum, completes a comprehensive optical analysis of thin film deposition.