Moisture Diffusion in Epoxy Molding Compounds Filled With Particles

1998 ◽  
Vol 123 (1) ◽  
pp. 47-51 ◽  
Author(s):  
M. Uschitsky ◽  
E. Suhir
Keyword(s):  
Integrated Circuits ◽  
Thermal Stresses ◽  
Experimental Studies ◽  
Moisture Sorption ◽  
Moisture Diffusion ◽  
Filler Concentration ◽  
Mechanical Reliability ◽  
High Concentration ◽  
Molding Compounds ◽  
Plastic Packages

Mechanical reliability of epoxy molding compounds in plastic packages of integrated circuits (IC) is greatly affected by the compound ability to absorb moisture. Accordingly, the objective of the study is to evaluate the effect of moisture sorption on the mechanical properties of the compound. Experimental studies were conducted to evaluate the moisture diffusion in compounds with different, from moderate to high, concentration of silica and alumina nitride fillers. The weight-gained analysis indicated that the moisture diffusion was of non-Fickian type and depended mainly on the specimen’s relative humidity and the filler concentration. We found that although the hygro-thermal stresses, caused by moisture diffusion, were relatively low, such diffusion led to an appreciable decrease in the compound’s strength. Moisture diffusion can result also in a substantial increase in the material’s plasticity. The obtained results can be helpful in the analysis of the mechanical behavior of molding compounds employed in electronic packaging. These results can be used to better understand and to improve the reliability of plastic packages of IC devices.

Effect of Wood Filler Concentration on Physical and Mechanical Properties of PLA-Based Composites

2021 ◽  
Vol 887 ◽  
pp. 110-115
Author(s):  
G.A. Sabirova ◽  
R.R. Safin ◽  
N.R. Galyavetdinov
Keyword(s):  
Mechanical Properties ◽  
Tensile Strength ◽  
Elastic Modulus ◽  
Composite Materials ◽  
Impact Strength ◽  
Wood Flour ◽  
Experimental Studies ◽  
Physical And Mechanical Properties ◽  
Filler Concentration ◽  
High Concentration

This paper presents the findings of experimental studies of the physical and mechanical properties of wood-filled composites based on polylactide (PLA) and vegetable filler in the form of wood flour (WF) thermally modified at 200-240 °C. It also reveals the dependence of the tensile strength, impact strength, bending elastic modulus, and density of composites on the amount of wood filler and the temperature of its thermal pre-modification. We established that an increase in the concentration of the introduced filler and the degree of its heat treatment results in a decrease of the tensile strength, impact strength and density of composite materials, while with a lower binder content, thermal modification at 200 °C has a positive effect on bending elastic modulus. We also found that 40 % content of a wood filler heated to 200 °C is sufficient to maintain relatively high physical and mechanical properties of composite materials. With a higher content of a wood filler, the cost can be reduced but the quality of products made of this material may significantly deteriorate. However, depending on the application and the life cycle of this product, it is possible to develop a formulation that includes a high concentration of filler.

Thermoelastic Behavior of Filled Molding Compounds: Composite Mechanics Approach

2000 ◽  
Vol 123 (3) ◽  
pp. 260-267 ◽  
Author(s):  
M. Uschitsky ◽  
E. Suhir ◽  
G. W. Kammlott
Keyword(s):  
Thermal Expansion ◽  
Integrated Circuit ◽  
Thermal Stresses ◽  
Volume Concentration ◽  
Molding Compounds ◽  
Low Level ◽  
Plastic Packages ◽  
Silica Fillers ◽  
Silicon Materials ◽  
Composite Mechanics

Reliability of epoxy molding compounds used in plastic packages of integrated circuit (IC) devices depends to a great extent on the level of thermal stresses. These are due primarily to the thermal expansion (contraction) mismatch of the epoxy and the silicon materials. In this analysis we assess the effect of silica fillers on the level of thermal stresses. We conclude that thermal stresses in the compound can indeed be reduced by the application of appropriate fillers. We found that the filler volume concentration does not have to be larger than 30 percent to keep the thermal stresses at a sufficiently low level. This number is close to the filler volume concentration of 30–40 percent in commercially available molding compounds. The obtained results and recommendations can be helpful in the analysis of stresses in, and physical design of, plastic packages.

Experimental studies on resistance characteristics of high concentration red mud in pipeline transport

2008 ◽  
Vol 14 (1) ◽  
pp. 157-161
Author(s):  
Xing Wang ◽  
Yuan-yuan Qu ◽  
Wei-wei Hu ◽  
Jie Chen ◽  
Xue-yi Zhao ◽  
...  
Keyword(s):  
Red Mud ◽  
Experimental Studies ◽  
Pipeline Transport ◽  
High Concentration

scholarly journals Blooms of bryozoans and epibenthic diatoms in an urbanized sandy Beach (Balneário Camboriú - SC - Brazil): dynamics, possible causes and biomass characterization

2017 ◽  
Vol 65 (4) ◽  
pp. 678-694 ◽  
Author(s):  
Leonardo Rubi Rörig ◽  
Maevi Ottonelli ◽  
Ana Gabriela Itokazu ◽  
Marcelo Maraschin ◽  
João Vitor Heberle Lins ◽  
...  
Keyword(s):  
Saturated Fatty Acids ◽  
Experimental Studies ◽  
Growth Conditions ◽  
Adjacent Area ◽  
High Concentration ◽  
Local Pollution ◽  
Organic Debris ◽  
Quality Of Water ◽  
Low Concentrations ◽  
Environmental Health Problem

Abstract Balneário Camboriu (SC - Brazil) is a touristic city where the disordered growth of the urban population and the implementation of coastal works without proper evaluation generated environmental impacts and affected the sanitary quality of water and sediment of Camboriu River and marine adjacent area. One of the most recent and alarming phenomena observed are the blooms of invasive bryozoans (Arboscuspis bellula and Membraniporopsis tubigera) associated with epibenthic diatoms (Amphitetras antediluviana and Biddulphia biddulphiana). Several clues associate these phenomena, started in 2003, with the excess of nutrients and organic matter in the Camboriú cove and large coastal works such as dredging, landfills and construction of jetties, leading to changes in benthic ecological structure. Being an aesthetic and environmental health problem, the concern of the scientific community and government agencies intensified as the occurrences become more frequent and persistent. This research addresses this issue through environmental and experimental studies. Samplings of the benthic material collected by boat and diving, and blooms monitoring were the environmental approach. The laboratory work included the algal isolation and culture, in addition to growth conditions assessment and chemical biomass analysis. Monitoring data showed a seasonal trend in the blooms, with more conspicuous events in warmer months. Diatoms increase in abundance in colder months and bryozoans in the warmer ones. The diatom A. antediluviana, predominant in the blooms, grew satisfactorily in laboratory cultivation, showing better growth in media with higher concentrations of silicate and phosphate. Bryozoans showed slow growth in laboratory conditions. The deposited material collected in the environment showed low concentrations of saturated fatty acids, but the high biomass suggest a possible use for biofuels production. Biomass samples dominated by bryozoans showed moderate antimicrobial activity against Klebsiella pneumoniae. The explanation for the occurrence of these blooms are still inconclusive, but there is considerable evidence that it is a synergistic effect between the high concentration of bacteria and organic debris in the water related to local pollution and the elimination of natural competitors by coastal works.

Plasma Surface Modification of Silica and its Application in Epoxy Molding Compounds for Large-Scale Integrated Circuits Packaging

2010 ◽  
Vol 158 ◽  
pp. 184-188 ◽  
Author(s):  
Ming Shan Yang ◽  
Lin Kai Li ◽  
Jian Guo Zhang
Keyword(s):  
Surface Modification ◽  
Acrylic Acid ◽  
Integrated Circuits ◽  
Plasma Polymerization ◽  
High Speed ◽  
Large Scale ◽  
Treatment Time ◽  
Rf Plasma ◽  
Formaldehyde Resin ◽  
Molding Compounds

The surface modification of silica for epoxy molding compounds (EMC) was conducted by plasma polymerization using RF plasma (13.56MPa), and the modification factors such as plasma power, gas pressure and treatment time were investigated systematically in this paper. The monomers utilized for the plasma polymer coatings were pyrrole, 1,3-diaminopropane, acrylic acid and urea. The plasma polymerization coating of silica was characterized by FTIR, contact angle. Using the silica treated by plasma as filler, ortho-cresol novolac epoxy as main resin, novolac phenolic-formaldehyde resin as cross-linking agent and 2-methylmizole as curing accelerating agent, the EMCs used for the packaging of large-scale integrated circuits were prepared by high-speed pre-mixture and twin roller mixing technology. The results have shown that the surface of silica can be coated by plasma polymerization of pyrrole, 1,3-diaminopropane, acrylic acid and urea, and the comprehensive properties of EMC were improved.

scholarly journals Environmental Characteristics of Modern Systems of Domestic Use of Fuel. Part 2. Pollutants Formation by Natural Gas Combustion in Atmospheric Burners: Experimental Studies

2020 ◽  
Vol 63 (5) ◽  
pp. 450-461
Author(s):  
B. S. Soroka ◽  
V. V. Horupa
Keyword(s):  
Thermal Power ◽  
Experimental Studies ◽  
Environmental Indicators ◽  
Gas Pressure ◽  
Operating Conditions ◽  
National Academy Of Sciences ◽  
High Concentration ◽  
Hydrocarbon Gases ◽  
Absolute Level ◽  
Toxic Emissions

The Gas Institute of the National Academy of Sciences of Ukraine performs comprehensive studies of the formation of toxic emissions in the flame of atmospheric burners and beyond the visible burning cones (“rich” primary flame). The experiments are based on the proven significant content of harmful substances in the combustion products of gas fuel in household appliances and on direct contact of consumers with gas emissions during the operation of the stoves. A methodology for the experimental researches of the harmful emissions formation has been proposed while the computerized firing rig serving as the diagnostic facility has been developed for studying the combustion of hydrocarbon gases in the burners of household stoves. Carbon oxides CO and nitrogen oxides NO and NO2 are considered as toxic emissions, while the primary air excess coefficient and the heat load of the burner are considered as variable parameters. Under operating conditions of a gas stove, its variable characteristics are the gas pressure in front of the nozzle of the atmospheric burner and its thermal power. When optimizing the design of burners, the determinant value of the stability of burning, energy and environmental indicators of fuel combustion is the coefficient of excess of primary air λpr at a given gas pressure before the burner. The influence of this coefficient on the formation of CO, NO, NO2 is established, and the possibility of emissions with a high concentration of nitrogen dioxide is proved. Since the concentration of [NO] decreases with an increase in λpr, and the absolute level of [NO2] concentrations is not significantly affected by the value of λpr, it is determined that the proportion of [NO2] concentration in the [NOx] = [NO] + [NO2] compound increases with an increase in the primary air excess coefficient.

Experimental Studies of the Reliability of Interconnect Trees

2000 ◽  
Vol 612 ◽  
Author(s):  
S.P. Hau-Riege ◽  
C.V. Thompson
Keyword(s):  
Integrated Circuits ◽  
Computer Aided Design ◽  
Void Nucleation ◽  
Experimental Studies ◽  
Single Layer ◽  
Electrical Current ◽  
Tree Structures ◽  
Current Configuration ◽  
Line Passing ◽  
Reliability Assessments

AbstractThe electromigration resistance of simple straight-line interconnects is usually used to estimate the reliability of complex integrated circuits. This is generally inaccurate, and overly conservative at best. The shapes and connectedness of interconnects is not accounted for in standard reliability assessments. We have identified the interconnect tree as the fundamental reliability unit. An interconnect tree consists of connected conducting line segments lying within a single layer of metallization, and terminating at two or more nodes at which there is a diffusion barrier such as a W-filled via. We performed electromigration experiments on the simplest tree structures, such as ‘L’- and ‘T’-shaped interconnects, as well as straight lines with an additional via in the middle of the line, passing currents of different magnitudes and directions through the limbs of the trees. We found that metal limbs ending in other limbs can act as reservoirs for electromigrating metal atoms. Passive reservoirs, which are limbs that do not carry electrical current, are generally beneficial for reliability, whereas limbs that do carry electrical current, called active reservoirs, can be beneficial or detrimental, depending on the direction and magnitude of the current in the reservoir. However, our experiments show that bends in interconnects do not affect their reliability significantly. We also found that the reliability of an interconnect tree can be conservatively estimated by considering void-growth and void-nucleation-limited failures at the most heavily stressed junction in the tree, which can be found by analyzing the geometry and current configuration. Our experimentally verified model for tree reliability can be used with layout tools for reliability-driven computer-aided design (RCAD), through ranking of the reliabilities of trees in order to identify areas at risk from electromigration damage.

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