Wet Clean Induce Pattern Collapse Mechanism Study

2012 ◽  
Vol 187 ◽  
pp. 253-256 ◽  
Author(s):  
C.C. Yang ◽  
C.C. Ko ◽  
H. Ou Yang ◽  
K.F. Chen ◽  
Y.Y. Peng ◽  
...  
Keyword(s):  
Aspect Ratio ◽  
Surfactant Solution ◽  
Future Generation ◽  
Collapse Mechanism ◽  
Mechanism Study ◽  
Induce Pattern ◽  
Dry Etch ◽  
First Time ◽  
Low K

Pattern collapse phenomenon was first time observed in BEOL application with the integration of ultra low-k film scheme. With the dimension and pitch shrinkage, the pattern collapse defects are getting worse during wet clean process. In this study, the line collapse defects can be significantly reduced by adding surfactant solution to the rinse liquid. Moreover, higher aspect ratio (>4) will also deteriorate the collapse window. In addition, the kink or bowing trench profile will induce localized stress at the interface. Accordingly, optimization of both wet clean and dry etch process are the successful keys to solve line collapse issue toward future generation and beyond.

scholarly journals Isolation and characterization of a new cold-active protease from psychrotrophic bacteria of Western Himalayan glacial soil

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Saleem Farooq ◽  
Ruqeya Nazir ◽  
Shabir Ahmad Ganai ◽  
Bashir Ahmad Ganai
Keyword(s):  
Specific Activity ◽  
Temperature Range ◽  
Psychrotrophic Bacteria ◽  
Isolation And Characterization ◽  
Cold Active ◽  
Active Protease ◽  
Quantitative Screening ◽  
First Time ◽  
Low K

AbstractAs an approach to the exploration of cold-active enzymes, in this study, we isolated a cold-active protease produced by psychrotrophic bacteria from glacial soils of Thajwas Glacier, Himalayas. The isolated strain BO1, identified as Bacillus pumilus, grew well within a temperature range of 4–30 °C. After its qualitative and quantitative screening, the cold-active protease (Apr-BO1) was purified. The Apr-BO1 had a molecular mass of 38 kDa and showed maximum (37.02 U/mg) specific activity at 20 °C, with casein as substrate. It was stable and active between the temperature range of 5–35 °C and pH 6.0–12.0, with an optimum temperature of 20 °C at pH 9.0. The Apr-BO1 had low Km value of 1.0 mg/ml and Vmax 10.0 µmol/ml/min. Moreover, it displayed better tolerance to organic solvents, surfactants, metal ions and reducing agents than most alkaline proteases. The results exhibited that it effectively removed the stains even in a cold wash and could be considered a decent detergent additive. Furthermore, through protein modelling, the structure of this protease was generated from template, subtilisin E of Bacillus subtilis (PDB ID: 3WHI), and different methods checked its quality. For the first time, this study reported the protein sequence for psychrotrophic Apr-BO1 and brought forth its novelty among other cold-active proteases.

Non-directed highly para-selective C-H functionalization of TIPS-protected phenols promoted by a proton shuttle

2021 ◽  
Author(s):  
Jingyao Geng ◽  
Zhang Fang ◽  
Guangliang Tu ◽  
Yingsheng Zhao
Keyword(s):  
Bioactive Molecules ◽  
Protecting Group ◽  
Mechanism Study ◽  
Phenol Derivatives ◽  
Site Selectivity ◽  
Palladium Catalyzed ◽  
Direct Functionalization ◽  
Poor Site ◽  
Site Selective ◽  
First Time

Abstract Palladium-catalyzed non-directed C-H functionalization provides an efficient approach for direct functionalization of arenes, but it usually suffers from poor site selectivity, limiting its wide application. Herein, it is reported for the first time that the proton shuttle of 3,5-dimethyladamantane-1-carboxylic acid (1-DMAdCO2H) can affect the site selectivity during the C-H activation step in palladium-catalyzed non-directed C-H functionalization, leading to highly para-selective C-H olefination of TIPS-protected phenols. This transformation displayed good generality in realizing various other para-selective C-H functionalization reactions such as hydroxylation, halogenation, and allylation reactions. A wide variety of phenol derivatives including bioactive molecules of triclosan, thymol, and propofol, were compatible substrates, leading to the corresponding para-selective products in moderate to good yields. A preliminary mechanism study revealed that the spatial repulsion factor between proton shuttle and bulky protecting group resulted in the selective C-H activation at the less sterically hindered para-position. This new model non-directed para-selective C-H functionalization can provide a straightforward route for remote site-selective C-H activations.

scholarly journals Foam Formation and Interaction with Porous Media

Coatings ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 143 ◽  
Author(s):  
Phillip Johnson ◽  
Mauro Vaccaro ◽  
Victor Starov ◽  
Anna Trybala
Keyword(s):  
Porous Media ◽  
Critical Micelle Concentration ◽  
Sodium Dodecyl ◽  
Surfactant Solution ◽  
Foam Formation ◽  
Compression Device ◽  
Time Interaction ◽  
The Media ◽  
Soft Porous Media ◽  
First Time

Foams are a common occurrence in many industries and many of these applications require the foam to interact with porous materials. For the first time interaction of foams with porous media has been investigated both experimentally and theoretically by O. Arjmandi-Tash et al. It was found that there are three different regimes of the drainage process for foams in contact with porous media: rapid, intermediate and slow imbibition. Foam formation using soft porous media has only been investigated recently, the foam was made using a compression device with soft porous media containing surfactant solution. During the investigation, it was found that the maximum amount of foam is produced when the concentration of the foaming agent (dishwashing surfactant) is in the range of 60–80% m/m. The amount of foam produced was independent of the pore size of the media in the investigated range of pore sizes. This study is expanded using sodium dodecyl sulphate (SDS), which has the same critical micelle concentration as the commercial dishwashing surfactant, where the foam is formed using the same porous media and compression device. During the investigation, it was found that 10 times the critical micelle concentration (CMC) is the optimum concentration for a pure SDS surfactant solution to create foam. Any further increase in concentration after that point resulted in no further mass of foam being generated.

Modeling of Thermo-Mechanical Stresses in Copper Interconnect/Low-k Dielectric Systems

2005 ◽  
Author(s):  
Y.-L. Shen
Keyword(s):  
Structural Integrity ◽  
Temperature Response ◽  
Future Generation ◽  
Interface Fracture ◽  
Deformation Pattern ◽  
Barrier Layers ◽  
Copper Interconnect ◽  
On Chip ◽  
Interconnect Systems ◽  
Low K

Systematic finite element analyses are carried out to model the thermomechanical stresses in on-chip copper interconnect systems. Constitutive behavior of encapsulated copper films, determined by experimentally measuring the stress-temperature response during thermal cycling, is used in the model for predicting stresses in copper interconnect/low-k dielectric structures. Various combinations of oxide and polymer-based low-k dielectric schemes are considered. The evolution of stresses and deformation pattern in the dual-damascene copper, barrier layers, and the dielectrics is seen to have direct connections to the structural integrity of contemporary and future-generation devices. In particular, stresses experienced by the thin barrier layers and the mechanically weak low-k dielectrics are critically assessed. A parametric analysis on the influence of low-k material properties is also conducted. Practical implications in reliability issues such as voiding, interface fracture, electromigration and dielectric failure are discussed.

Effects of oxygen and fluorine on the dry etch characteristics of organic low-k dielectrics

1999 ◽  
Vol 17 (2) ◽  
pp. 372 ◽  
Author(s):  
M. R. Baklanov ◽  
S. Vanhaelemeersch ◽  
H. Bender ◽  
K. Maex
Keyword(s):  
Dry Etch ◽  
Low K

Giant Piezoelectric and Dielectric Relaxations in Statistical Mixtures

2006 ◽  
Vol 115 ◽  
pp. 209-214
Author(s):  
A.I. Chernobabov ◽  
A.V. Turik ◽  
G.S. Radchenko ◽  
S.A. Turik
Keyword(s):  
Dielectric Permittivity ◽  
Aspect Ratio ◽  
Heterogeneous Systems ◽  
Dielectric Constants ◽  
Dielectric Spectra ◽  
Physical Mechanisms ◽  
Dielectric Relaxations ◽  
First Time

The effective complex piezoelectric and dielectric constants of disordered heterogeneous systems of the type of statistical mixtures with the components in the form of spheroid-shaped particles equally oriented but randomly arranged in space were studied. It has been found for the first time that in such systems there appears a giant piezoelectric enhancement accompanied by a giant relaxation of piezoelectric coefficients and the dielectric permittivity. Piezoelectric and dielectric spectra differ significantly from the Debye ones and are of Davidson-Cole type. The influence of the aspect ratio of spheroids on the effects under consideration was studied. The physical mechanisms responsible for the anomalies in the behavior of piezoelectric coefficients and the dielectric permittivity were considered.

scholarly journals ACTIVE AEROELASTIC CONTROL OF LIFTING SURFACES VIA JET REACTION LIMITER CONTROL

2006 ◽  
Vol 16 (09) ◽  
pp. 2559-2574 ◽  
Author(s):  
CHRISTINA RUBILLO ◽  
PIERGIOVANNI MARZOCCA ◽  
ERIK BOLLT
Keyword(s):  
Chaotic Dynamics ◽  
Control Plant ◽  
Future Generation ◽  
Practical Implementation ◽  
Flexible Wings ◽  
Aeroelastic System ◽  
Aircraft Wings ◽  
Lifting Surfaces ◽  
Control Feedback ◽  
First Time

In this paper we present, the design and modeling of the novel nonlinear limiter control feedback control plant [Myneni et al., 1999; Corron et al., 2000; Corron & Pethel, 2002], applied for the first time here in an aeroelastic system, and actuated as a jet reaction torquer control of a wing with potentially chaotic dynamics. This study will provide a better understanding of the nonlinear dynamics of the open/closed-loop aeroelasticity of flexible wings with either steady or unsteady aerodynamic loads. The limiter control can be applied to either the plunging or pitching characteristic of the wing or to both of them. We show that the control can effectively suppress Limit Cycle Oscillations (LCO) and chaos well beyond the nominal flutter speed. This could lead to a practical implementation of the control mechanism on actual and future generation aircraft wings via implementation of a combination of propulsive/jet type forces, micro surface effectors and fluidic devices. Analysis of this control produced favorable results in the suppression of LCO amplitude and increased flutter boundaries for plunging and pitching motion. The limiting control has asymptotically zero power, and is simply implemented, making it a feasible solution to the problem of the chaotic dynamics of the oscillating airfoil.

TiN Metal Hardmask Residue Removal Formulation Development for Advanced Porous Low-K and Cu Interconnect Application

2014 ◽  
Vol 219 ◽  
pp. 217-220 ◽  
Author(s):  
Hua Cui
Keyword(s):  
Aspect Ratio ◽  
Metal Deposition ◽  
Formulation Development ◽  
Chemical Cleaning ◽  
Residue Removal ◽  
Profile Control ◽  
Cu Interconnect ◽  
Tin Metal ◽  
Technology Nodes ◽  
Low K

TiN metal hardmask has been used to improve etch selectivity to low-k materials and thereby gain better profile control. For 14 nm and smaller technology nodes, it is required that the TiN hardmask is completely removed in order to improve the aspect ratio for subsequent reliable metal deposition. Thus, a chemical cleaning formulation with high TiN etch selectivity toward Cu and low-k is required.

Interfacial Adhesion of Nanoporous Zeolite Thin Films

Materials ◽  
2004 ◽  
Author(s):  
Lili Hu ◽  
Junlan Wang ◽  
Zijian Li ◽  
Shuang Li ◽  
Yushan Yan
Keyword(s):  
Thin Films ◽  
Interfacial Adhesion ◽  
High Performance ◽  
Interfacial Strength ◽  
Synthesis Process ◽  
Seeded Growth ◽  
Thermal Methods ◽  
Laser Spallation ◽  
First Time ◽  
Low K

Nanoporous zeolite thin films are promising candidates as future low-k materials. During the integration with other semiconducting materials, the high stresses resulted from the synthesis process can cause the film to fracture or delaminate from the substrates. Evaluating the interfacial adhesion of zeolite thin films is very important in achieving high performance low-k materials. In this work, laser spallation technique is utilized to investigate the interfacial strength of zeolite thin films from three different synthesis processes. The preliminary results show that the fully crystalline zeolite thin films from hydro-thermal in-situ and seeded growth methods have a stronger interface than that from the spin-on process. Effort is also being made to compare the interfacial strength of the zeolite films between the two hydro-thermal methods. This is the first time that the interfacial strength of zeolite thin films is quantitatively evaluated. The results have great significance in the future applications of low-k zeolite thin films.

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