Seok-Woo Yun

Influence of CuO Addition to (Ba0.5,Sr0.5)TiO3 Ceramics on Sintering Behavior and Dielectric Properties

CuO additives were added to the (Ba0.5,Sr0.5)TiO3 ceramics to lower the sintering temperature. 1–5 wt% CuO were selected and employed as the sintering aid. Low-temperature co-fired ceramic technologies were popular process technologies to manufacture microwave devices. In this study, crystalline and electrical properties of CuO doped (Ba0.5,Sr0.5)TiO3 ceramics were investigated to know the low temperature sintering properties. It was found that the addition of CuO to (Ba0.5,Sr0.5)TiO3 could lower the sintering temperature from 1350 to 1150°C. Sintering temperature dependence of shrinkage rate and mechanism for CuO doped (Ba0.5,Sr0.5)TiO3 ceramics have been investigated and discussed. Also, the crystalline structure of CuO-doped BST ceramics will be discussed by X-ray diffraction (XRD) method.

Low Temperature Sintering Behavior and Giant Dielectric Properties of CuO Doped (Ba0.5Sr0.5)TiO3 Ceramics

The effects of CuO additions on the sintering temperature and dielectric properties of (Ba0.5Sr0.5)TiO3 ceramic have been investigated by employing X-ray diffraction analysis, and dielectric properties measurements. In this research, 1–5 wt% CuO was added to the (Ba0.5Sr0.5)TiO3 powders to reduce the sintering temperature. CuO-doped (Ba0.5Sr0.5)TiO3 ceramics were sintered from 750 to 1350°C to confirm the sintering temperature with various dopants, respectively. It was found that the addition of CuO to (Ba0.5Sr0.5)TiO3 could lower the sintering temperature from 1350 to 1150°C. Moreover giant dielectric permittivity was observed in the 5 wt% CuO doped (Ba0.5Sr0.5)TiO3 ceramics.

Study on the Sintering Temperature and Electrical Properties of CuO Doped (Ba 0.5 ,Sr 0.5 )TiO 3 Ceramics

The influence of CuO addition on what of the ceramics was studied. The sintering temperature of ceramics was lowered by the addition of CuO additives. The 1 - 5 wt% CuO were selected and employed as the sintering aids. Low-Temperature Co-fired Ceramic technologies are popular technologies used in the manufacture of microwave devices. In this study, crystalline and electrical properties of CuO doped ceramics were investigated to determine the low temperature sintering properties. The addition of CuO to lowered the sintering temperature from to . The dependence of the sintering temperature shrinkage rate and mechanism of CuO doped ceramics are investigated and discussed. Also, the crystalline structure of CuO - doped ceramics is discussed by the X-ray diffraction (XRD) method.

A Study of the Dielectric Properties of the Silver-Tantalate-Niobate Thick Films

Low loss perovskite niobates and tantalates have been placed on a short list of functional materials for future technologies. In this study, we fabricated Ag(Ta,Nb) thick films on the substrates by the screen printing method. The Ag(Ta,Nb) powders were fabricated by the mixed oxide method. The sintering temperature and time were and 2 hrs, respectively. The results of XRD analysis showed that the specimens employed in this study had the pesudo cubic structure. The dielectric permittivity and loss tangent of the films have been characterized from 1 kHz to 1 MHz. Also the dielectric permittivity and loss tangent were measured from 303 K to 393 K. The electrical properties of the film are also discussed.

Processing Study for the Micro Pillar for Piezoelectric Energy Harvest

In this study, the piezoelectric energy harvester was investigated employing the pillar structure with the diameter size of 50~500 um. Usually, the aspect ratio between the height and diameter was related with the piezoelectric performance. High aspect ratio was showed the low electric noise and high piezoelectric properties than low aspect ratio. Therefore, we have selected the Su-8 photo-resist and modified lithography process to manufacture the pillar structure with height above the 250 . In this presentation, we will report the process and properties of micro pillar structure based on the PMN-PZT (Pb-PbZrTiO) materials.