Abstract: Disclosed are a silicon derivative, a liquid crystal composition comprising the same, and a compensation film for a liquid crystal display device using the same liquid crystal composition. More particularly, the silicon derivative is a liquid crystal material of a high-quality view angle compensation film, which improves a contrast ratio measured at a tilt angle when compared to a contrast ratio measured from the front surface and minimizes color variations in a black state depending on view angles.

Abstract: Disclosed are a vinylsulfone derivative, a liquid crystal composition comprising the same, and a compensation film for a liquid crystal display device using the same liquid crystal composition. More particularly, the vinylsulfone derivative is a liquid crystal material of a high-quality view angle compensation film, which improves a contrast ratio measured at a tilt angle when compared to a contrast ratio measured from the front surface and minimizes color variations in a black state depending on view angles.

Abstract: Disclosed herein is a polymer-ceramic dielectric composition. The dielectric composition comprises a polymer and a ceramic dispersed in the polymer wherein the ceramic is composed of a material having a perovskite structure represented by ABO3 and a metal oxide dopant and has an electrically charged surface. According to the dielectric composition, the surface of the ceramic is electrically charged to induce space-charge polarization (or interfacial polarization) at the polymer/ceramic interface, resulting in an increase in dielectric constant. Since the dielectric composition has a high dielectric constant particularly in a low-frequency range, it can be suitably used to produce decoupling capacitors. Further disclosed are a capacitor and a printed circuit board that use the dielectric composition.

Abstract: Disclosed herein is a composite dielectric composition having a small variation of capacitance with temperature, comprising a combination of a polymer matrix exhibiting a positive or negative variation of capacitance with temperature and a ceramic filler exhibiting a negative or positive variation of capacitance with temperature which is reciprocal to that of the polymer matrix; and a signal-matching embedded capacitor prepared by using the same composition. Particularly, the present invention provides a composite dielectric composition comprising a polymer matrix exhibiting a positive or negative variation of capacitance with temperature and a ceramic filler exhibiting a variation of capacitance which is reciprocal to that of the polymer matrix; and a signal-matching embedded capacitor formed of the same composition and having a variation of capacitance with temperature, ? C/C×100(%), of not more than 5%.

Abstract: A method of manufacturing a thin film capacitor includes steps of: performing recrystallization heat treatment on a metal foil; forming a dielectric layer on a top surface of the recrystallized metal foil; heat treating the metal foil and the dielectric layer; and forming an upper electrode on a top surface of the heat-treated dielectric layer. The recrystallization heat treatment prevents the oxidation of a metal foil, by which a dielectric layer can be heat treated at a high temperature, thereby improving electric properties of a thin film capacitor and the reliability of a product.

Abstract: A cerium oxide powder for one-component CMP slurry, which has a specific surface area of 5 m2/g or more, and a ratio of volume fraction of pores with a diameter of 3 nm or more to that of pores with a diameter less than 3 nm of 8:2˜2:8. A method for preparing the same, a one-component CMP slurry comprising the same as an abrasive material, and a method of shallow trench isolation using the one-component CMP slurry are also disclosed. The CMP slurry causes no precipitation of the cerium oxide powder even if it is provided as a one-component CMP slurry, because the CMP slurry uses, as an abrasive material, cerium oxide powder that is obtained via a low-temperature calcination step, optionally a pulverization step, and a high-temperature calcination step and has a high pore fraction and low strength.

Abstract: Disclosed is a composition for forming a dielectric, which is applied to an embedded capacitor with a high dielectric constant, a capacitor produced using the composition, and a PCB provided with the capacitor. The composition includes 40 to 99 vol % of thermoplastic or thermosetting resin, and 1 to 60 vol % of semiconductive filler. Alternatively, the composition includes 40 to 95 vol % of thermoplastic or thermosetting resin, and 5 to 60 vol % of semiconductive ferroelectric substance. Furthermore, the present invention provides the capacitor, produced using the composition, and the PCB provided with the capacitor. Therefore, the dielectric, which is produced using the composition including the semiconductive filler or semiconductive ferroelectric substance, is advantageous in that the dielectric constant is high and a dielectric loss is low. The dielectric is usefully applied to produce an embedded capacitor with the high dielectric constant and the PCB provided with the embedded capacitor.

Abstract: Disclosed herein is a resin composition and ceramic/polymer composite for dielectric layers of embedded capacitors having a high dielectric constant, a dielectric layer of a capacitor manufactured therefrom, and a printed circuit board including the dielectric layer. In addition, a method of increasing temperature stability and a dielectric constant of the ceramic/polymer composite for dielectric layers of embedded capacitors is also provided. The resin composition for embedded capacitors includes 5-30 wt % of at least one resin selected from the group consisting of bisphenol-A epoxy resins, bisphenol-F epoxy resins and combinations thereof, 60-85 wt % of at least one resin selected from the group consisting of novolac-type epoxy resins, polyimides, cyanate esters and combinations thereof, and 10-30 wt % of a multi-functional epoxy resin, and the ceramic/polymer composite includes such a resin composition.

Abstract: Disclosed are a silicon-containing compound, a liquid crystal composition comprising the same compound, and a liquid crystal display device comprising a liquid crystal layer prepared from the liquid crystal composition. The silicon-containing compound, which forms the liquid crystal composition, has low viscosity and high positive dielectric anisotropy. Therefore, it is possible to provide a liquid crystal display device, which has a fast response time and can be driven at a low voltage.

Abstract: Disclosed are a silicon-containing compound, a liquid crystal composition comprising the same compound, and a liquid crystal display device comprising a liquid crystal layer prepared from the liquid crystal composition. The silicon-containing compound, which forms the liquid crystal composition, has low viscosity and high negative (?) dielectric anisotropy. Therefore, it is possible to provide a liquid crystal display device, which has a fast response time and can be driven at a low voltage.

Abstract: Described is a radially multi-branched polymer represented by the following formula (I): ABi (I), which includes a central molecule (A) to which side-branches (B) are bonded in at least three positions (i?3). Also described are methods for preparing a multi-branched polymer as well as a porous insulating film including a multi-branched polymer.