• 한국세라믹학회지
• /
• 제34권11호
• /
• pp.1173-1181
• /
• 1997

Effects of particle size distribution of alumina ceramics on behaviors of tape casting were investigated with emphases on the rheological characteristic of slurry, green density, green sheet strength, and sintering density. For the control of particle size distribution of alumina, the commercial grade low soda alumina, which had different mean particle size of 3.58 ${\mu}{\textrm}{m}$ and 0.42 ${\mu}{\textrm}{m}$, were chosen and blended together. As results, the mixing of 80 wt% fine powder and 20 wt% coarse powder(designated to FC20) led to the increase of packing density and strength of green sheet, and made it easy to handle during processing without lowering of sintering density. Besides, the pseudoplastic behavior of slurry decreased with increase of the fraction of coarse alumina powder.

• 대한전기학회:학술대회논문집
• /
• 대한전기학회 2004년도 하계학술대회 논문집 C
• /
• pp.1600-1604
• /
• 2004

As the integrated circuit device shrinks to the smaller dimension, the chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric(IMD) layer with free-defect. The effect of alternative commerical slurries pads, and post-CMP cleaning alternatives are discuess, with removal rate, scratch dentisty, surface roughness, dishing, erosion and particulate density used as performance metrics. we investigated the performance of $SnO_2$-CMP process using commonly used silica slurry, ceria slurry, tungsten slurry. This study shows removal rate and nonuniformity of $SnO_2$ thin film used to gas sensor by using Ceria, Silica, W-Slurry after CMP process. This study also shows the relation between partical size and CMP with partical size analysis of used slurry.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 반도체 재료 센서 박막재료 전자세라믹스
• /
• pp.93-96
• /
• 2004

As the integrated circuit device shrinks to the smaller dimension, the chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric(IMD) layer with free-defect. The effect of alternative commerical slurries pads, and post-CMP cleaning alternatives are discuess, with removal rate, scratch dentisty, surface roughness, dishing, erosion and particulate density used as performance metrics. we investigated the performance of $SnO_2$-CMP process using commonly used silica slurry, ceria slurry, tungsten slurry. This study shows removal rate and nonuniformity of $SnO_2$ thin film used to gas sensor by using Ceria, Silica, W-Slurry after CMP process. This study also shows the relation between partical size and CMP with partical size analysis of used slurry.

• 한국전기전자재료학회:학술대회논문집
• /
• 한국전기전자재료학회 2003년도 추계학술대회 논문집 Vol.16
• /
• pp.184-187
• /
• 2003

As the integrated circuit device shrinks to the smaller dimension, the chemical mechanical polishing (CMP) process was required for the global planarization of inter-metal dielectric(IMD) lyaer with free-defect. The effect of alternative commerical slurries pads, and post-CMP cleaning alternatives are discuess, with removal rate, scratch dentisty, surface roughness, dishing, erosion and particulate density used as performance metrics. we investigated the performance of $SnO_2-CMP$ process using commonly used silica slurry, ceria slurry, tungsten slurry. This study shows removal rate and nonuniformity of $SnO_2$ thin film used to gas sensor by using Ceria, Silica, W-Slurry after CMP process. This study also shows the relation between partical size and CMP with partical size analysis or used slurry.

• 한국전기전자재료학회논문지
• /
• 제28권12호
• /
• pp.781-786
• /
• 2015

It is necessary for ferrite sheets to be fabricated with high packing density for excellent electrical properties and high strength. In this study, the relationship between the warpage and the packing density of ferrite green sheet, was investigated with amount variation of organic additives. With 0.4 wt% of dispersant, the packing density was about 48% and warpage appeared 0.5~1.3 mm high. With 1.4 wt% of dispersant, the packing density increased up to 57% and warpage appeared 0.8~2.1 mm high. With high packing density, warpage appeared along the edges of specimen, while with low packing density, deformation appeared over whole specimen inhomogeneously. It is thought that inhomogeneous deformation after sintering came from the inhomogeneity in green sheet prepared with badly dispersed slurry. With good homogeneity in green sheet from well-dispersed slurry, isotropic shrinkage is thought to have occurred along the distance from center to edges of specimen during sintering.

• 한국세라믹학회지
• /
• 제55권4호
• /
• pp.337-343
• /
• 2018

The influence of solid loading in the slurry composition on the morphology of 3Y-TZP granules fabricated by two-fluid spray drying was investigated for solid contents varying between 30 wt% and 50 wt%. The resulting 3Y-TZP granules showed a sphere-like shape with diameters of $40-70{\mu}m$. However, a donut-like shape and a few cracks were observed on the granule surfaces fabricated using the slurry with 50 wt% solid content. The green density after cold isostatic pressing at 200 MPa was $2.1-2.2g/cm^3$, and a homogeneous fracture surface was obtained by complete destruction of granules. After sintering at $1500^{\circ}C$ for 2 h, all specimens had relative densities of 96.2 - 98.3%. With increasing solid content, the relative density decreased from 98.3% to 96.2%, but the grain size increased from $0.3{\mu}m$ to $0.6{\mu}m$. Highly sinterable zirconia granule powder could be obtained by controlling the slurry composition.

• 한국재료학회지
• /
• 제16권11호
• /
• pp.715-718
• /
• 2006

Porous hydroxyapatite (HAp) scaffolds have been prepared by using the slurry including HAp and magnesia based on the replication of polymer sponge substrate. The influence of MgO content in slurry on the pore morphology and size, density, porosity, and mechanical strength of porous HAp scaffolds was investigated. The obtained scaffolds with average pore sizes ranging 150 to 300 mm had open, relatively uniform, and interconnected porous structure regardless of MgO content. As the MgO content increased, the pore network frame of scaffolds became to be relatively stronger, even though the pore size was not much changed. The compressive strength of the scaffolds increased rapidly with the increase of MgO content because of increasing the pore wall thickness and density of the scaffolds. As a result, the porosity, density, and compressive strength of the porous HAp scaffolds prepared by the sponge method were significantly affected by the addition of MgO.

• 한국전기전자재료학회논문지
• /
• 제32권6호
• /
• pp.483-489
• /
• 2019

For machine learning techniques, a large amount of high-quality material property data should be accumulated. In this study, several data for an alumina tape casting process were produced with the variables of slurry viscosity, gap size, and coating speed. The alumina tapes were manufactured in the range of 1,000~6,000 cps for slurry viscosity, $300{\sim}1,000{\mu}m$ for gap size, and 0.5~2.0 m/min for coating speed. As a result, the lower the viscosity, coating speed, and gap size, the more pore-free tapes could be manufactured. The viscosity of the slurry limited the minimum thickness of the tape. Green sheets with high packing density were manufactured from the slurry of 100~6,000 cps slurry viscosity, coating speed of 0.5 m/min, and a $300{\sim}500{\mu}m$ gap size.

• 한국세라믹학회지
• /
• 제37권5호
• /
• pp.511-515
• /
• 2000

The effect of Ba2+ ion dissolution with different pH and amount of PAA on microstructural changes of green and sintered bodies and its electrical properties was studied in aqueous nano-size BaTiO3 slurry system. The dissolution of Ba2+ was least at strong base, pH 10.8 and by addition of amount of 0.15 wt% PAA. The green body with the lowest of dissolution of Ba2+ at pH 10.8 and 0.15 wt% PAA had minimum values of average pore size, 40nm and shown high increase of sintered density. The compact sintered at 125$0^{\circ}C$ for 2 hr with highest Ba2+ dissolution had low density and dielectric constant due to abnormal grian growth. However, the sintered body with the lowest Ba2+ dissolution had high sintered density and then shown high dielectric constant.

• 한국분말재료학회지
• /
• 제24권2호
• /
• pp.147-152
• /
• 2017

Spherical-type zirconia granules are successfully fabricated by a spray-drying process using a water solvent slurry, and the change in the green density of the granule powder compacts is examined according to the organic polymers used. Two organic binders, polyvinyl alcohol (PVA) and 2-hydroxyethyl methacrylate (HEMA), which are dissolved in a water solvent and have different degrees of polymerization, are applied to the slurry with a plasticizer (polyethylene glycol). The granules employing a binder with a higher degree of polymerization (PVA) are not broken under a uniaxial press; consequently, they exhibit a poor green density of $2.4g/cm^3$. In contrast, the granule powder compacts employing a binder with a lower degree of polymerization (HEMA) show a higher density of $2.6g/cm^3$ with an increase in plasticizer content. The packing behavior of the granule powders for each organic polymer system is studied by examining the microstructure of the fracture surface at different applied pressures.