Chen K.-Y.,National Taiwan University |
Huang C.-W.,Chung Yuan Christian University |
Wu M.,Yageo Corporation |
Wei W.-C.J.,National Taiwan University |
Hsueh C.-H.,National Taiwan University
Journal of Materials Science: Materials in Electronics | Year: 2014
Characterization of the mechanical properties of small components is a significant issue. For the multilayer ceramic capacitor (MLCC), direct loading by conventional facilities is not suitable because of its small size. To date, the standard method used to determine MLCC's mechanical properties is board flex test; i.e., mounting the capacitor onto a printed circuit board (PCB) and applying bending to the entire system. Failure is defined as cracking or capacitance loss of the MLCC when the mounted PCB is subjected to a specified deflection, and the measurements are usually performed after the test. In this case, characterization of the mechanical properties of MLCCs is qualitative. The purpose of the present study was to quantitatively characterize the mechanical properties of MLCCs. Specifically, the acoustic emission was used to detect cracking of MLCCs during the board flex test. To confirm cracking-induced acoustic emission, telemicroscope was used to perform the in situ observation of cracking. Finite element analyses were also performed to analyze the stress field resulting from the test to compare with the observed cracking path. In addition, nanoindentation was used to explore the mechanical properties of the constituents of MLCCs in the nanoscale. Our work not only allows identification and understanding of the fracture origin, but also provides guidelines in the material design. © 2013 Springer Science+Business Media New York. Source
Yageo Corporation | Date: 2014-08-29
A titanium compound-containing core-shell powder includes a plurality of core-shell particles, each of which includes a core body and a shell layer encapsulating said core body. The core body is electrically conductive. The shell layer includes a crystal that is selected from titanate oxides having a perovskite structure and titanate oxides having a spinel structure. The core body and the shell layer are chemically bonded to each other.
Yageo Corporation | Date: 2011-10-25
The present invention relates to a chip resistor and method for manufacturing the same. The method includes the following steps of: (a) providing a substrate and a resistor layer; (b) attaching the resistor layer to the substrate; (c) forming a first metal layer; (d) forming a plurality of through holes; (e) forming a connecting metal layer in the through holes to electrically connect the resistor layer and the first metal layer; (f) patterning the resistor layer to form a plurality of first resistor bodies; (g) forming a plurality of first protecting layers to protect the first resistor bodies; and (h) proceeding a singulation process along a plurality of cutting lines to form a plurality of chip resistors. Whereby, no alignment problem occurs and the yield can be raised.
Yageo Corporation | Date: 2014-06-06
The disclosure provides a chip resistor including: a substrate, two first electrodes, two second electrodes, a resistive layer, at least one protection layer and at least one coating layer. The protection layer covers part of the two first electrodes, and includes at least two overlay sides and at least one overlay plane. The coating layer covers the at least two overlay sides, the at least one overlay plane, and part of the two first electrodes and the two second electrodes. The chip resistor uses the two overlay sides and the overplay plane to extend a distance between the two first electrodes and the outside. Therefore, it is difficult for the airborne sulfur, sulfides and sulfur-containing compounds to enter and react with the two first electrodes. Thus, the chip resistor can resist corrosion of harmful substances such as sulfur, sulfides and sulfur-containing compounds or halogens on the electrodes.
Yageo Corporation | Date: 2012-11-19
The present invention relates to an antenna having a connecting circuit, which includes a substrate, a grounding metal strip, a first radiating metal strip, a second radiating metal strip and a connecting circuit. The first radiating metal strip is not connected to the grounding metal strip or the second radiating metal strip. The connecting circuit connects different positions on the grounding metal strip and on the second radiating metal strip, so as to form a plurality of resonant paths of different lengths between the grounding metal strip and the second radiating metal strip. Thereby, the frequency of the antenna varies between different values, so that the range of the application and the practicality of the antenna are increased.