• Journal of the Semiconductor & Display Technology
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• v.9 no.1
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• pp.5-10
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• 2010

Among a variety of cleaning processes, the cryogenic carbon dioxide ($CO_2$) cleaning has merits because it is highly efficient in removing very fine particles, innoxious to humans and does not produce residuals after the cleaning, which enables us to extend its area of coverage in the semi-conductor fabrication society. However, the cryogenic carbon dioxide cleaning method has some technical research issues in aspect to particles' adhesion and removal. To resolve these issues, performing an analysis for the identification of particle adhesion mechanism is needed. In this study, a research was performed by a theoretical approach. To this end, we extended the G-T (Greenwood-Tripp) model by applying the JKR (Johnson-Kendall-Roberts) and Lennard-Jones potential theories and the statistical characteristics of rough surface to investigate and identify the contact, adhesion and deformation mechanisms of soft or hard particles on the rough substrate. The statistical characteristics of the rough surface were taken into account through the employment of the normal probability distribution function of the asperity peaks on the substrate surface. The effects of surface roughness on the pull-off force for these particles were examined and discussed.

• Journal of Adhesion and Interface
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• v.3 no.4
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• pp.19-26
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• 2002

In order to study the toughening mechanism of rubber modified polycarbonate, the sequence of development of micro-voids was investigated by real-time small angle X-ray scattering with Synchrotron radiation (SR-SAXS). The used test method was wedge test. The scattering intensity increases with increasing penetration depth of wedge, i.e. applied strain. The increase is due to the micro-void formation during deformation. This micro-void was uniformly developed in matrix and was different from large-void due to internal cavitation of rubber particle and/or debonding between rubber particle and polycarbonate matrix. The micro-void was developed at the critical strain and the radius of micro-void is around $600{\AA}$. Above the critical strain the size of micro-void remains almost constant with increasing applied strain. However, the population of micro-void increased with applied strain.

• Journal of Adhesion and Interface
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• v.12 no.1
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• pp.1-10
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• 2011

An automated reaction calorimeter was used to directly monitor the rate of emulsion polymerization of vinyl acetate using poly(vinyl alcohol) (PVAs) having different degrees of blockiness. By using this technique in conjunction with other off-line measurements of the evolution of particle size distributions, important details of the process were observed. No constant graft rate period was observed for both low and high initial monomer-water ratios. The gel effect was observed for the low monomer-water ratio recipe. The particle size distributions were broad (particle diameter 40~100 nm) and bimodal. Continuous nucleation was observed to be accompanied by 'limited aggregation' and flocculation during the particle growth stages. It was speculated to be due to the occurrence of the extensive 'limited aggregation' and chain transfer to PVA leading to grafting.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.529-529
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• 2007

Ruthenium (Ru) is a white metal and belongs to platinum group which is very stable chemically and has a high work function. It has been widely studied to apply Ru as an electrode material in memory devices and a Cu diffusion barrier metal for Cu interconnection due to good electrical conductivity and adhesion property to Cu layer. To planarize deposited Ru layer, chemical mechanical planarization(CMP) was suggested. However, abrasive particle can induce particle contamination on the Ru layer surface during CMP process. In this study, zeta potentials of Ru and interaction force of alumina particles with Ru substrate were measured as a function of pH. The etch rate and oxidation behavior were measured as a function of chemical concentration of several organic acids and other acidic and alkaline chemicals. PRE (particle removal efficiency) was also evaluated in cleaning chemical.

• Proceedings of the International Microelectronics And Packaging Society Conference
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• 2002.05a
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• pp.109-114
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• 2002

The adhesion of electroless plated Ni layer on Al/Si substrates has been investigated. The zincating treatment was conducted with a conventional method and a modified method. In a modified method, ultrasonic agitation was applied during zincating. Adhesion strength was evaluated by a pull-off test. The ultrasonic agitation during zincating increased the nucleation density of Zn particles and refined Zn particle size. the adhesion strength of electroless Ni layer deposited on the modified zincated surface was higher than that on the conventionally zincated surface. the improvement of adhesion was attributed to the fine and dense Zn particles.

• Journal of Adhesion and Interface
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• v.3 no.1
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• pp.13-19
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• 2002

We have studied on the surface and adhesion properties for acrylic terpolymers, having both hydrophobic and hydrophilic side chains, synthesized via solution polymerization. In order to develop a waterborne material. we tried to synthesize these terpolymers via emulsion polymerization. The polymeric emulsion synthesized was mainly composed of methyl methacrylate (MMA), methoxy-polyethyleneglycol methacrylate (MPEGMA) having hydrophilic side chains and methoxypolypropyleneglycol methacrylate (MPEGMA) having hydrophobic side chains. The viscosities of this series increased with an increase in the content of the co-monomer such as MPEGMA and (MPEGMA). This behavior resulted in the increase in the diameter and heterogeneity of the emulsion particle via AFM observation. Furthermore. the tensile adhesion strength and 90-degree peel strength of the adhesive of these polymeric emulsions were measured. In the case of polymeric emulsion composed of the same content of both hydrophilic and hydrophobic component, the adhesion property showed the highest value. However, since the adhesion properties as a practical applicable adhesive were poor, some improvements were required. When the composition above was modified with butyl acrylate (BA), the improvement effect on adhesion strength was accepted. In particular, 90-degree peel strength increased up to a maximum of 400% of the original value.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.8
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• pp.1465-1474
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• 2001

The dispersion stability of particles and the adsorption of surfactant were examined as a fundamental environment to adhesion of particulate soil to fabric. The adsorption of surfactant on the PEF fabrics decreased with the addition of electrolytes and decreased with increasing the ionic strengths showed similar tendency to PET fabric. And the dispersion force of $\alpha$-Fe$_2$O$_3$particles decreased with the addition of electrolyte. The adhesion of particulate soil to fabric, increased with decreasing the adsorption of surfactant the correlation between the two was high at low ionic strength. The correlation between the adsorption of surfactants on $\alpha$-Fe$_2$O$_3$ particles and the adhesion of particles to fabric was smaller as shown in the correlation between the adsorption of surfactants on fiber substrate and the adhesion of particles on fabric. However, the correlation between the adhesion of particles to fabric and the stability of particle dispersion was relatively more significant.

• Journal of Adhesion and Interface
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• v.18 no.1
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• pp.25-32
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• 2017

For application to display module junction process, the silk screen printing based on UV curable acrylic pressure sensitive adhesive(PSA) with silica nano-particles and the rheological properties were studied to investigate the effect on printability and adhesion. The monomers for PSA were based on 2-ethylhexyl acrylate(2-EHA) and acrylic acid(AA) 93:7, butyl acylate(BA), 2-hydroxyethyl acrylate(2-HEA) and tetrahydrofurfuryl acrylate(THFA) were added. Additionally, hydrophobic and hydrophilic nano-particles AEROSIL R974 and AEROSIL 200 were added, respectively. When the ratio of nano-particle was used above 4 or 7 phr, G' and ${\eta}^*$ were increased significantly. When the ratio of AEROSIL 200 was used above 7 phr, the penetration property was decreased during the silk screen printing. We found that the adhesion was decreased with increasing the nano-particle content, and it was decreased in the case of the hydrophilic nano-particle AEROSIL 200.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.380-390
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• 1993

Effect of interfacial electrical conditions on adhesion of ${\alpha}-Fe_2O_3$ particles to PET fabric and the removal of ${\alpha}-Fe_2O_3$ particles from PET fabric, were investigated as functions of pH, electrolyte and ionic strength. The ${\zeta}$ potential of PET fiber and ${\alpha}-Fe_2O_3$ particles in the electrolyte solution were measured by streaming potential and microelectrophoresis methods respectively. The potential energy of interaction between ${\alpha}-Fe_2O_3$ particles and PET fabric were calculated by using the heterocoagulation theory for a sphere-plate model. The negative ${\zeta}$ potential of ${\alpha}-Fe_2O_3$ particle and PET fiber increased with pH, and then decreased certain pH and isoelectric points of ${\alpha}-Fe_2O_3$ particles and PET fiber were pH 6.5 and pH 3.5, respectively. The negative ${\zeta}$ potential of ${\alpha}-Fe_2O_3$ particle and PET fiber affected by electrolytes, were relatively high with polyanion electrolytes in solutions and were low with neutral salts. However, at surfactant solution, ${\zeta}$ potential was levelled off. The influence of the ionic strength on the ${\zeta}$ potential of ${\alpha}-Fe_2O_3$ particle was small but the negative ${\zeta}$ potential of PET fiber increased with the ionic strength. In the presence of anionic surfactant, the ${\zeta}$ potential of ${\alpha}-Fe_2O_3$ particle and PET fiber increased regardless of solution conditions. The interaction energy between ${\alpha}-Fe_2O_3$ particle and PET fabric increased with pH. The interaction energy was relatively high with polyanion electrolytes in solution, and the influence of ionic strength on the interaction energy was small, and the effective thickness of electrical double layer increased with decreasing the ionic strength.

• Korean Journal of Metals and Materials
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• v.46 no.7
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• pp.464-470
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• 2008

Metallic nanostructures have great potential for bio-chemical sensor applications due to the excitation of localized surface plasmon and its sensitive response to environmental change. Unlike the commonly explored absorption-based sensing, the optical scattering provides single particle detection scheme. For the localized surface plasmon resonance spectroscopy, the metallic nanostructures with controlled shape and size have been usually fabricated on adhesion-layer pre-coated transparent glass substrates. In this study, we calculated the optical scattering properties of plasmonic Au nanodisc using a discrete dipole approximation method and analyzed the effect of adhesion layer on them. Our result also indicates that there is a trade-off between the surface plasmon damping and the capability of supporting nanostructures in determining the optimal thickness of adhesion layer. Marginal thickness of Ti adhesion layer for supporting Au nanostructures fabricated on a silica glass substrate was experimentally analyzed by an adhesion strength test using a nano-indentation technique.