Morphological and Structural Evolution of an Ultra-low-k Dielectric During the Porogen Removal

2006 ◽  
Vol 914 ◽  
Author(s):  
Diane Rebiscoul ◽  
Héléne Trouvé ◽  
Bruno Remiat ◽  
Laurence Clerc ◽  
Didier Louis ◽  
...  
Keyword(s):  
Refractive Index ◽  
Etch Rate ◽  
Structural Evolution ◽  
Integration Scheme ◽  
Thermal Cure ◽  
Crosslinking Degree ◽  
Cure Temperature ◽  
The Impact ◽  
Low K ◽  
Complex Gradient

AbstractThe use of porous ultra-low-k materials between interconnections for sub 45nm technologies has introduced some barrier diffusion and mechanical problems. In order to avoid the problems caused by the porosity, a hybrid dense material (porogen and matrix) can be used in an alternate integration scheme. In this approach, the porogen is removed after CMP steps by a thermal cure or UV assisted thermal cure. In this work, we have first characterized the impact of the temperature and the duration of the thermal cure on the material. The crosslinking degree increases and the porogen amount decreases with increasing cure temperature. The most important impact of the curing duration happens between 350°C and 400°C. The increase of the curing duration leads to an increase of the porogen loss and a decrease of the refractive index. Secondly, in order to assess the structure of the layer as a function of the depth, the material was etched in a 0.05% HF solution and then characterized. According to the temperature and duration of the cure, the etch-rate can vary as a function of the material depth. This variation is related to a complex gradient inside the material.

Comparative crosstalk performance analysis of different configurations of heterogeneous multicore fiber

2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Umar Farooque ◽  
Rakesh Ranjan
Keyword(s):  
Refractive Index ◽  
Mode Coupling ◽  
The Other ◽  
Heterogeneous Multicore ◽  
Coupled Mode ◽  
The Core ◽  
Bending Radius ◽  
Multicore Fiber ◽  
The Impact ◽  
Core Pitch

AbstractIn order to select the heterogeneous multicore fiber (MCF) configuration with ultra-low crosstalk and low peak bending radius, comparative crosstalk analysis have been done for the three possible core configurations, namely, Configuration 1 - different refractive index (R.I.) and different radius, Configuration 2 - different R.I., and Configuration 3 - different radius. Using the coupled mode equation and the simplified expressions of mode coupling coefficient (MCC) for different configurations of heterogeneous cores, the crosstalk performance of all the heterogeneous MCF configurations along with the homogeneous MCF have been investigated analytically with respect to core pitch (D) and fiber bending radius (${R}_{b}$). Further, these expressions of MCC have been extended to obtain the simplified expressions of MCC for the estimation of crosstalk levels in respective trench-assisted (TA) heterogeneous MCF configurations. It is observed from the analysis that in Configuration 1, crosstalk level is lowest and the rate of decrease in the crosstalk with respect to the core pitch is highest compared to the other configurations of heterogeneous MCF. The values of crosstalk obtained analytically have been validated by comparing it with the values obtained from finite element method (FEM) based numerical simulation results. Further, we have investigated the impact of a fixed percent change (5%) in the core parameters (radius and/or R.I.) of one of the core of a homogeneous MCF, to realize the different heterogeneous MCF configurations, on the variations in crosstalk levels, difference in the mode effective refractive index of the core 1 and core 2 ($\Delta {n}_{eff}={n}_{eff1}-{n}_{eff2}$), and the peak bending radius (${R}_{pk}$). For the same percent variations (5%) in the core parameters (radius and/or R.I.) of different configurations of cores (Config. 1-Config. 3), Config. 1 MCF has highest variation in $\Delta {n}_{eff}$ value compared to other configurations of MCF. Further, this highest variation in $\Delta {n}_{eff}$ value of Config. 1 MCF results in smallest peak bending radius. The smaller value of peak bending radius allows MCF to bend into smaller radius. Therefore, Configuration 1 is the potential choice for the design of MCF with smaller peak bending radius and ultra-low crosstalk level compared to the other configurations of SI-heterogeneous MCF.

scholarly journals Synthesis of PVA/CeO2 Based Nanocomposites with Tuned Refractive Index and Reduced Absorption Edge: Structural and Optical Studies

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1570
Author(s):  
Shujahadeen B. Aziz ◽  
Elham M. A. Dannoun ◽  
Dana A. Tahir ◽  
Sarkawt A. Hussen ◽  
Rebar T. Abdulwahid ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Absorption Edge ◽  
Ceo2 Nanoparticles ◽  
Poly Vinyl Alcohol ◽  
Optical Parameters ◽  
Single Oscillator Model ◽  
Vis Spectroscopy ◽  
The Impact ◽  
Host Polymer

In the current study, polymer nanocomposites (NCPs) based on poly (vinyl alcohol) (PVA) with altered refractive index and absorption edge were synthesized by means of a solution cast technique. The characterization techniques of UV–Vis spectroscopy and XRD were used to inspect the structural and optical properties of the prepared films. The XRD patterns of the doped samples have shown clear amendments in the structural properties of the PVA host polymer. Various optical parameters were studied to get more insights about the influence of CeO2 on optical properties of PVA. On the insertion of CeO2 nanoparticles (NPs) into the PVA matrix, the absorption edge was found to move to reduced photon energy sides. It was concluded that the CeO2 nanoparticles can be used to tune the refractive index (n) of the host polymer, and it reached up to 1.93 for 7 wt.% of CeO2 content. A detailed study of the bandgap (BG) was conducted using two approaches. The outcomes have confirmed the impact of the nanofiller on the BG reduction of the host polymer. The results of the optical BG study highlighted that it is crucial to address the ɛ” parameter during the BG analysis, and it is considered as a useful tool to specify the type of electronic transitions. Finally, the dispersion region of n is conferred in terms of the Wemple–DiDomenico single oscillator model.

Geometrically nonlinear static and dynamic analysis of CNT reinforced laminated composite plates: A finite element study

2021 ◽  
pp. 095440622110089
Author(s):  
Balakrishna Adhikari ◽  
BN Singh
Keyword(s):  
Finite Element ◽  
Free Vibration ◽  
Dynamic Response ◽  
Integration Scheme ◽  
Static And Dynamic Analysis ◽  
Finite Element Study ◽  
Nonlinear Eigenvalues ◽  
Nonlinear Static ◽  
The Impact ◽  
Element Study

In this paper, a finite element study is conducted using the Green Lagrange strain field based on vonKarman assumptions for the geometric nonlinear static and dynamic response of the laminated functionally graded CNT reinforced (FG-CNTRC) composite plate. The governing equations for determining the nonlinear static and dynamic behavior of the FG-CNTRC plate are derived using the Lagrange equation of motion based on Reddy's higher order theory. Using the direct iteration technique, the nonlinear eigenvalues for analyzing the free vibration response are obtained and the nonlinear dynamic responses of the FG-CNTRC plate are encapsulated based on the nonlinear Newmark integration scheme. The impact of the amplitude of vibration on mode switching phenomena and the consequence of the duration of the pulse on the free vibration regime of the plate are outlined. Also, the effect of time dependent loads is studied on the normal stresses of the plate. Furthermore, the impact on the nonlinear static and dynamic response of the laminated FG-CNTRC plate of various parameters such as span-thickness ratio (b/h ratio), aspect ratio (a/b ratio), different edge constraints, CNT fiber gradation, etc. are also studied.

scholarly journals Raman scattering in high-refractive-index nanostructures

Nanophotonics ◽  
2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Søren Raza ◽  
Anders Kristensen
Keyword(s):  
Raman Spectroscopy ◽  
Refractive Index ◽  
Raman Scattering ◽  
Bound States ◽  
Stimulated Raman Scattering ◽  
Dielectric Materials ◽  
High Refractive Index ◽  
Surface Enhanced Raman Spectroscopy ◽  
Raman Enhancement ◽  
The Impact

AbstractThe advent of resonant dielectric nanomaterials has provided a new path for concentrating and manipulating light on the nanoscale. Such high-refractive-index materials support a diverse set of low-loss optical resonances, including Mie resonances, anapole states, and bound states in the continuum. Through these resonances, high-refractive-index materials can be used to engineer the optical near field, both inside and outside the nanostructures, which opens up new opportunities for Raman spectroscopy. In this review, we discuss the impact of high-refractive-index nano-optics on Raman spectroscopy. In particular, we consider the intrinsic Raman enhancement produced by different dielectric resonances and their theoretical description. Using the optical reciprocity theorem, we derive an expression which links the Raman enhancement to the enhancement of the stored electric energy. We also address recent results on surface-enhanced Raman spectroscopy based on high-refractive-index dielectric materials along with applications in stimulated Raman scattering and nanothermometry. Finally, we discuss the potential of Raman spectroscopy as a tool for detecting the optical near-fields produced by dielectric resonances, complementing reflection and transmission measurements.

Advances in Test Wafer Reclaim Technology – Wet Stripping Porous Low-k Films with No Substrate Damage

2009 ◽  
Vol 145-146 ◽  
pp. 339-342 ◽  
Author(s):  
Mark Robson ◽  
Kristin A. Fletcher ◽  
Ping Jiang ◽  
Michael B. Korzenski ◽  
A. Upham ◽  
...  
Keyword(s):  
Film Thickness ◽  
Etch Rate ◽  
Oxide Growth ◽  
Semiconductor Processing ◽  
Related Cost ◽  
Increasing Demand ◽  
Wet Etch ◽  
Low K

In semiconductor processing, test wafers are used as particle monitors, film thickness monitors for deposition and oxide growth measurements, dry/wet etch rate monitors, CMP monitors, as well as characterizing new and existing equipment and processes. Depending on fab size and capacity, monthly test wafer usage can be tens of thousands or more. Due to the ever increasing demand for silicon between the IC and solar markets and the high cost of 300mm wafers, chip manufacturers are increasing their efforts to reduce overall spending on silicon - currently by far the largest non equipment related cost [1]. One approach taken by many chip makers is the concept of extending the usable life of test wafers by re-using them as many times as possible through a reclaim process.

scholarly journals Polycentric or monocentric, which kind of spatial structure is better for promoting the green economy? Evidence from Chinese urban agglomerations

2021 ◽  
Author(s):  
Yue Huang ◽  
Ruiwen Liao
Keyword(s):  
Spatial Structure ◽  
Structural Evolution ◽  
Development Planning ◽  
Urban Agglomeration ◽  
Green Economy ◽  
Economic Activities ◽  
Optimal Range ◽  
Urban Agglomerations ◽  
The Impact ◽  
Research Period

Abstract The green economy has gained worldwide attention, especially in the urban agglomerations where population and economic activities are highly concentrated. However, what kind of urban agglomeration spatial structure is more conducive to promoting the green economy? No clear conclusions have been made. Here, we study the impact of urban agglomeration spatial structure on the green economy, and also reveal how urban agglomeration spatial structure influences the three subsystems of green economy. We find that: (1) urban agglomeration spatial structural evolution is closely related to green economy, while in the research period, most urban agglomerations are not located in the optimal range of the spatial structure that drives the green economy. (2) Towards polycentric spatial structure is contributive to green economic growth, however, the excessively polycentric could not benefit green economy. (3) The evolution of urban agglomeration spatial structure exerts heterogenous impacts on the three subsystems when green economy is decomposed into economic subsystem, resources subsystem, and environmental subsystem. Towards polycentric is more conducive to the improvement of economic subsystem and resource subsystem, while, the tendency to monocentric drives the environmental subsystem development. (4) Lastly, our conclusions enlighten the urban agglomeration development planning and spatial mode for approaching a better performance in green economy.

Corrosion of Co in BEOL interconnects in dilute HF solution

2018 ◽  
Vol 282 ◽  
pp. 256-262
Author(s):  
Yuya Akanishi ◽  
Els Kesters ◽  
Quoc Toan Le ◽  
Frank Holsteyns
Keyword(s):  
Dissolved Oxygen ◽  
Etch Rate ◽  
Galvanic Corrosion ◽  
Barrier Structure ◽  
Corrosion Prevention ◽  
Atmospheric Air ◽  
The Impact

The impact of dissolved oxygen (O2) on cobalt (Co) corrosion in dilute HF (dHF) solution was studied. It was confirmed that Co etch rate was enhanced as the amount of dissolved O2 in the HF solution increased. The Co etch rate was also found to increase radially outward when performed on a single-wafer spin process in atmospheric air due to the uptake of O2 during the dispense process. The galvanic corrosion of Co was investigated with two types of structures with a Co/Cu interface in different dissolved O2 concentrations, i.e. (1) Co bump structures on Cu and (2) Cu lines with a Co/TaN liner/barrier structure. By controlling both the dissolved and the atmospheric O2 levels, galvanic corrosion prevention at the Co/Cu interface was achieved.

Highly dispersive optical soliton perturbation of Kudryashov’s arbitrary form having sextic-power law refractive index

2021 ◽  
Vol 35 (24) ◽  
Author(s):  
Ahmed M. Elsherbeny ◽  
Reda El-Barkouky ◽  
Aly R. Seadawy ◽  
Hamdy M. Ahmed ◽  
Rabab M. I. El-Hassani ◽  
...  
Keyword(s):  
Refractive Index ◽  
Power Law ◽  
Soliton Solutions ◽  
Research Paper ◽  
Optical Soliton ◽  
Integration Scheme ◽  
Arbitrary Form ◽  
Soliton Perturbation ◽  
Singular Soliton ◽  
Simple Integration

In this research paper, a simple integration scheme is executed to secure new dark and singular soliton solutions for the highly dispersive nonlinear Schrödinger’s equation having Kudryashov’s arbitrary form with generalized nonlocal laws and sextic-power law refractive index.

Enhancement and Modeling of Drain Current in Negative Capacitance Double Gate TFET

2021 ◽  
Author(s):  
SHIKHA U S ◽  
Rekha K James ◽  
Jobymol Jacob ◽  
Anju Pradeep
Keyword(s):  
Drain Current ◽  
Gate Oxide ◽  
Negative Capacitance ◽  
Double Gate ◽  
High K ◽  
Gate Control ◽  
Effect Transistor ◽  
Dimensional Simulation ◽  
The Impact ◽  
Low K

Abstract The drain current improvement in a Negative Capacitance Double Gate Tunnel Field Effect Transistor (NC-DG TFET) with the help of Heterojunction (HJ) at the source-channel region is proposed and modeled in this paper. The gate oxide of the proposed TFET is a stacked configuration of high-k over low-k to improve the gate control without any lattice mismatches. Tangent Line Approximation (TLA) method is used here to model the drain current accurately. The model is validated by incorporating two dimensional simulation of DG-HJ TFET with one dimensional Landau-Khalatnikov (LK) equation. The model matches excellently with the device simulation results. The impact of stacked gate oxide topology is also studied in this paper by comparing the characteristics with unstacked gate oxide. Voltage amplification factor (Av), which is an important parameter in NC devices is also analyzed.

scholarly journals Study of a Broadband Difference Interferometer Based on Low-Cost Polymer Slab Waveguides

Nanomaterials ◽  
2019 ◽  
Vol 9 (5) ◽  
pp. 729 ◽  
Author(s):  
Kazimierz Gut
Keyword(s):  
Refractive Index ◽  
Output Signal ◽  
Propagation Constant ◽  
Low Cost ◽  
Waveguide Layer ◽  
Propagation Path ◽  
Slab Waveguide ◽  
Polymer Waveguides ◽  
Materials Used ◽  
The Impact

A model and the waveguide parameters of a broadband, polymer-based slab waveguide difference interferometer is presented in this paper. The parameters were determined based on knowledge of the dispersion in the structure materials used to fabricate the waveguide. The impact of the waveguide layer thickness, propagation path length, and change in the waveguide cover refractive index on the output signal from the system was determined. It has been shown that the direction of the maximum shifting is determined by the thickness of the waveguide layer. A relationship describing the shift in the signal extrema for a change in the waveguide cover refractive index was derived. The results show that the use of a propagation constant simplifies the description of the interferometer. Polymer waveguides, although they have a small contrast in refractive indices, allow for large shifts in the maxima of the signal. The determined shifts in the output signal extrema for polymer waveguides are comparable, and these shifts are larger for some waveguide thicknesses compared to waveguides based on Si3N4.

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