Performance Comparisons of Abrasive Containing and Abrasive Free Slurries for Copper Low-k CMP

2002 ◽  
Vol 732 ◽  
Author(s):  
John Nguyen ◽  
Gerald Martin ◽  
Ron Carpio ◽  
Malcolm Grief ◽  
Somit Joshi
Keyword(s):  
Removal Rate ◽  
Low Cost ◽  
Copper Removal ◽  
Process Window ◽  
Low Friction ◽  
Cost Of Ownership ◽  
Percent Solid ◽  
Copper Cmp ◽  
Robust Process ◽  
Low K

AbstractThe commercially available abrasive containing slurries for copper CMP have shown some advantages in high removal rates, low friction at low down force, and minimal to no copper residues, regardless of the polisher architecture, either rotary, orbital, or linear polishing. However, the abrasive containing slurries have some disadvantages such as high dishing and erosion with more micro-scratches due to the presence of abrasives. In contrast, the abrasive free polishing slurry has lower removal rate, and seems to be sensitive to polishing architecture, but it has good planarization, low topography, less micro-scratches, and most importantly is insensitive to over-polish.At this stage, the best results for copper CMP are being achieved by the use of the multi-step and multi-slurry process in which copper is polished first, and barrier layers are polished with a different set of consumables. The intent of this paper is to focus on the first step, the copper removal step, and to compare different approaches for this first step; namely, the use of slurries containing abrasives with slurries that are free of abrasives on the orbital polisher. The combined process with low percent solid and small-sized abrasives for the bulk copper removal step and abrasive free polishing (AFP) slurry for the residual copper removal step on an orbital polisher has produced a very robust process window with excellent results including low topography, low erosion, insensitivity to over-polish and low cost of ownership.

scholarly journals Preparation and Characterization of High-Efficiency Magnetic Heavy Metal Capture Flocculants

Water ◽  
2021 ◽  
Vol 13 (13) ◽  
pp. 1732
Author(s):  
Yuanyuan Yu ◽  
Yongjun Sun ◽  
Jun Zhou ◽  
Aowen Chen ◽  
Kinjal J. Shah
Keyword(s):  
Heavy Metal ◽  
Reaction Time ◽  
High Efficiency ◽  
Removal Rate ◽  
Low Cost ◽  
Monomer Concentration ◽  
Synthesis Process ◽  
Response Surface Optimization ◽  
Metal Capture ◽  
Total Monomer Concentration

In this study, a high-efficiency magnetic heavy metal flocculant MF@AA was prepared based on carboxymethyl chitosan and magnetic Fe3O4. It was characterized by SEM, FTIR, XPS, XRD and VSM, and the Cu(II) removal rate was used as the evaluation basis for the preparation process. The effects of AMPS content, total monomer concentration, photoinitiator concentration and reaction time on the performance of MF@AA flocculation to remove Cu(II) were studied. The characterization results show that MF@AA has been successfully prepared and exhibits good magnetic induction characteristics. The synthesis results show that under the conditions of 10% AMPS content, 35% total monomer concentration, 0.04% photoinitiator concentration, and 1.5 h reaction time, the best yield of MF@AA is 77.69%. The best removal rate is 87.65%. In addition, the response surface optimization of the synthesis process of MF@AA was performed. The optimal synthesis ratio was finally determined as iron content 6.5%, CMFS: 29.5%, AM: 53.9%, AMPS: 10.1%. High-efficiency magnetic heavy metal flocculant MF@AA shows excellent flocculation performance in removing Cu(II). This research provides guidance and ideas for the development of efficient and low-cost flocculation technology to remove Cu(II) in wastewater.

scholarly journals Adsorption of copper ions on Magnolia officinalis residues after solid-phase fermentation with Phanerochaete chrysosporium

2019 ◽  
Vol 17 (1) ◽  
pp. 1173-1184 ◽  
Author(s):  
Fengyun Tao ◽  
Yangping Liu ◽  
Junliang Chen ◽  
Peng Wang ◽  
Qing Huo
Keyword(s):  
Chinese Medicine ◽  
Phanerochaete Chrysosporium ◽  
Solid Phase ◽  
Copper Ions ◽  
Removal Rate ◽  
Low Cost ◽  
Preparation Technique ◽  
Adsorption Enthalpy ◽  
Pseudo Second Order ◽  
Magnolia Officinalis

AbstractThe disposal of residues while manufacturing Chinese medicine has always been an issue that concerns pharmaceutical factories. Phanerochaete chrysosporium was inoculated into the residues of Magnolia officinalis for solid-phase fermentation to enzymatically hydrolyze the lignin in the residues and thus to improve the efficiency of removal of the copper ions from residues for the utilization of residues from Chinese medicine. With the increase in activities of lignin-degrading enzymes, especially during the fermentation days 6 to 9, the removal rate of copper ions using M. officinalis residues increased dramatically. The rate of removal reached the maximum on the 14th day and was 3.15 times higher than the initial value. The rate of adsorption of copper ions on the fermentation-modified M. officinalis residues followed the pseudo-second-order kinetics. The adsorption isotherms were consistent with the Freundlich models. The adsorption enthalpy was positive, indicating that it was endothermic and elevation in temperature was favorable to this adsorption process. The adsorption free energy was negative, implying the spontaneity of the process. The copper ions adsorbed could be effectively recovered using 0.2 M hydrochloric acid solution. After five successive cycles of adsorption-regeneration, the fermentation-modified M. officinalis residues exhibited a stable adsorption capacity and greater reusability. The M. officinalis residues fermented with P. chrysosporium are low-cost and environmentally friendly copper ions adsorbent, and this preparation technique realizes the optimum utilization of Chinese medicine residues.

Integrated Process for Textile Cotton Waste (TCW) Valorization: Waste-to-Energy and Wastewater Decontamination

2016 ◽  
Author(s):  
A. Ribeiro ◽  
C. Vilarinho ◽  
J. Araújo ◽  
J. Carvalho
Keyword(s):  
Raw Materials ◽  
Removal Rate ◽  
Low Cost ◽  
Calorific Value ◽  
Waste To Energy ◽  
Synthetic Wastewater ◽  
Small Scale ◽  
World Population ◽  
Cotton Waste ◽  
Textile Industries

The increasing of world population, industrialization and global consuming, existing market products existed in the along with diversification of raw materials, are responsible for an exponential increase of wastes. This scenario represents loss of resources and ultimately causes air, soils and water pollution. Therefore, proper waste management is currently one of the major challenges faced by modern societies. Textile industries represents, in Portugal, almost 10% of total productive transforming sector and 19% of total employments in the sector composed by almost 7.000 companies. One of the main environmental problems of textile industries is the production of significant quantities of wastes from its different processing steps. According to the Portuguese Institute of Statistics (INE) these industries produce almost 500.000 tons of wastes each year, with the textile cotton waste (TCW) being the most expressive. It was estimated that 4.000 tons of TCW are produced each year in Portugal. In this work an integrated TCW valorisation procedure was evaluated, firstly by its thermal and energetic valorisation with slow pyrolysis followed by the utilization of biochar by-product, in lead and chromium synthetic wastewater decontamination. Pyrolysis experiments were conducted in a small scale rotating pyrolysis reactor with 0.1 m3 of total capacity. Results of pyrolysis experiments showed the formation of 0,241 m3 of biogas for each kilogram of TCW. Results also demonstrated that the biogas is mostly composed by hydrogen (22%), methane (14 %), carbon monoxide (20%) and carbon dioxide (12%), which represents a total high calorific value of 12.3 MJ/Nm3. Regarding biochar, results of elemental analysis demonstrated a high percentage of carbon driving its use as low cost adsorbent. Adsorption experiments were conducted with lead and chromium synthetic wastewaters (25, 50 and 100 mg L−1) in batch vessels with controlled pH. It was evaluated the behaviour of adsorption capacity and removal rate of each metal during 120 minutes of contact time using 5, 10 and 50 g L−1 of adsorbent dosage. Results indicated high affinity of adsorbent with each tested metal with 78% of removal rate in chromium and 95% in lead experiments. This suggests that biochar from TCW pyrolysis may be appropriated to wastewaters treatment, with high contents of heavy metals and it can be an effective alternative to activated carbon.

scholarly journals Co-Design of CVT-Based Electric Vehicles

Energies ◽  
2021 ◽  
Vol 14 (7) ◽  
pp. 1825
Author(s):  
Caiyang Wei ◽  
Theo Hofman ◽  
Esin Ilhan Caarls
Keyword(s):  
Cooling System ◽  
Design Method ◽  
Low Cost ◽  
Cost Effective ◽  
Speed Ratio ◽  
Air Flow Rate ◽  
Cost Of Ownership ◽  
Variable Transmission ◽  
Primary Focus ◽  
Design Freedom

For an electric vehicle (EV) with a continuously variable transmission (CVT), a novel convex programming (CP)-based co-design method is proposed to minimize the total-cost-of-ownership (TCO). The integration of the electric machine (EM) and the CVT is the primary focus. The optimized system with co-design reduces the TCO by around 5.9% compared to a non-optimized CVT-based EV (based on off-the-shelf components) and by around 2% compared to the EV equipped with a single-speed transmission (SST). By taking advantage of the control and design freedom provided by the CVT, the optimal CVT, EM and battery sizes are found to reduce the system cost. It simultaneously finds the optimal CVT speed ratio and air-flow rate of the cooling system reducing the energy consumption. The strength of co-design is highlighted by comparing to a sequential design, and insights into the design of a low-power EV that is energy-efficient and cost-effective for urban driving are provided. A highly integrated EM-CVT system, which is efficient, low-cost and lightweight, can be expected for future EV applications.

Effects of Alkaline Nano-SiO2 Abrasive on Planarization of 300mm Copper Patterned Wafer

2013 ◽  
Vol 634-638 ◽  
pp. 2949-2954
Author(s):  
Xin Liang Tang ◽  
Yu Ling Liu ◽  
Hong Yuan Zhang ◽  
Jie Bao
Keyword(s):  
Removal Rate ◽  
Chemical Mechanical Planarization ◽  
Initial Step ◽  
Step Height ◽  
Copper Removal ◽  
Copper Wafers

Silica abrasive plays an important role in chemical mechanical planarization (CMP) of copper. In this paper, effect of different silica abrasive concentrations on copper removal rate and planarization performance of copper was investigated. The results show that the copper removal rate was increased as the concentration of silica abrasive increase. However, excessive abrasive will lead to a decreased copper removal rate. The initial step height values of the multilayer copper wafers were all about 2500Å, and after being polished for 30s, the remaining values of step height of slurry A, B, C and D were 717 Å, 906 Å, 1222 Å and 1493 Å. It indicates that alkaline copper slurries with different abrasive concentrations all had a good planarization performance on copper patterned wafer CMP. As the abrasive concentration increased, the planarization capability was enhanced.

Low friction bio-inspired polydopamine/polytetrafluoroethylene coating performance in hydrodynamic bearings

2021 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Marius Rutkevičius ◽  
Jimmy Dong ◽  
Darren Tremelling ◽  
Julia Viertel ◽  
Samuel Beckford
Keyword(s):  
Large Scale ◽  
Journal Bearing ◽  
Low Cost ◽  
Optical Microscope ◽  
Polymer Coatings ◽  
Industrial Applications ◽  
Low Friction ◽  
Coating Performance ◽  
Content Type ◽  
Coating Delamination

Purpose Low friction polymer coatings able to withstand high loadings and many years of continuous operation are difficult to formulate at low cost, but could find many applications in industry. This study aims to analyze and compare friction and wear performance of novel polydopamine/polytetrafluoroethylene (PDA/PTFE) and traditional tin Babbitt coatings applied to an industrial journal bearing. Design/methodology/approach This paper tested PTFE based coating, co-deposited with PDA, a biopolymer allowing sea mussels to adhere to ocean rocks. This coating was deposited on flat steel substrates and on a curved cast iron hydrodynamic journal bearing surface. The flat substrates were analyzed with a tribometer and an optical microscope, while the coated bearing liners were tested in an industrial laboratory setting at different speeds and different radial loads. Findings PDA/PTFE coating showed 2-3 times lower friction compared to traditional tin Babbitt for flat substrates, but higher friction in the bearing liners. PDA/PTFE also showed considerable wear through coating delamination and abrasion in the bearing liners. Research limitations/implications Five future modifications to mitigate coating flaws are provided, which include modifications to coating thickness and its surface finish. Originality/value While the novel coating showed excellent results on flat substrates, coating performance in a large scale bearing was found to be poor. This study shows that coating preparation needs to be improved to avoid frictional losses and unwanted damage to bearings. We provide several routes that could improve coating performance in industrial applications.

Preparation of Nanosized TiO2-Photocatalyst From-Sludge (TFS) and the Characteristics of Concrete Sidewalk Blocks Using TFS

2021 ◽  
Vol 21 (7) ◽  
pp. 3882-3886
Author(s):  
Yong-Wook Jung ◽  
Jong Kyu Kim
Keyword(s):  
Methylene Blue ◽  
Photocatalytic Degradation ◽  
Air Pollutants ◽  
Removal Rate ◽  
Low Cost ◽  
Sewage Treatment ◽  
Mixing Ratio ◽  
Tio2 Photocatalyst ◽  
And Performance ◽  
Nanosized Tio2

In this study, nano-sized low cost titanium dioxide (TFS) was prepared using sludge from sewage treatment and performance was verified. To remove air pollutants, the photocatalytic degradation of methylene blue and efflorescence characteristics is assessed according to the mixing ratio of the nano-sized TFS by applying them to concrete sidewalk blocks. The photocatalytic degradation performance of concrete sidewalk blocks shows that the methylene blue removal rate of specimens containing 2.5%, 5%, and 10% of nano-sized TFS is 29%, 27%, and 38%, respectively. When the nano-sized TFS is mingled on the surface of the sidewalk block, the performance of anti-corrosion and antifouling showed excellency mainly due to the moisture blocking derived by the antifouling function of photocatalysts.

Development of “New Abrasive-Free Copper CMP Solutions” BASED on Electrochemical and Film Analysis Method

2002 ◽  
Vol 732 ◽  
Author(s):  
Jin Amanokura ◽  
Yasuo Kamigata ◽  
Masanobu Habiro ◽  
Hiroshi Suzuki ◽  
Masanobu Hanazono
Keyword(s):  
Removal Rate ◽  
Analysis Method ◽  
Film Analysis ◽  
Cu Complex ◽  
Erosion Properties ◽  
Copper Cmp ◽  
Cu Cmp ◽  
Complex Film

AbstractAbrasive-free Cu CMP solutions have been developed to reduce micro-scratches and obtain minimized dishing and erosion properties. During the development of the solutions, some electrochemical examinations were performed. One of the most instructive knowledge was obtained through the Tafel plot. Other attractive data were obtained through Cu complex film analysis. On the basis of these studies were developed and released newly formulated abrasive-free Cu CMP solutions with a high Cu removal rate and excellent topography performance. Mechanism of polishing by applying abrasive-free Cu CMP solutions is also discussed in this paper.

Performance Evaluation of Magnetohydrodynamic Bearing

2005 ◽  
Author(s):  
H. Hirani ◽  
P. Samanta
Keyword(s):  
High Speed ◽  
Permanent Magnets ◽  
Magnetic Levitation ◽  
Hydrodynamic Lubrication ◽  
Low Cost ◽  
Low Friction ◽  
Oil Flow ◽  
Hybrid Bearing ◽  
Commercial Applications ◽  
Structural Simplicity

The present paper introduces a concept of hydrodynamic-permanent-magnetic hybrid bearing. The hybrid bearing uses repulsive force between permanent magnets and fluid force developed due to relative speed in a single assembly arrangement. Repulsive type passive magnetic levitation has advantage of minimum starting torque. Hydrodynamic lubrication mechanism has advantage of low friction at medium and high speed. This hybridization will be an attractive choice in commercial applications for its low cost, structural-simplicity and no metal-to-metal contact. An experimental setup is designed and developed to investigate the performance characteristics of proposed concept of hybrid bearing. Minimum film thickness, oil flow rate, and temperature rise are recorded at various speed- and load- conditions. Results are plotted to demonstrate the behavior of hybrid bearing arrangement.

Sign in / Sign up

Export Citation Format

Share Document