• Advances in materials Research
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• v.2 no.3
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• pp.133-140
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• 2013

This paper aims to focus on the microwave processing of thick films which is a fast, cheap technique and could be the alternative to the currently used conventional high temperature processing technique. Microwave processing has gained worldwide acceptance as a novel method for heating and sintering a variety of materials, as it offers specific advantages in terms of speed, energy efficiency, process simplicity, finer microstructures and lower environmental hazards. Silver conducting thick films were prepared and processed in the household microwave oven. The films sintered at different time period by keeping the other parameter such as microwave power, film thickness etc constant. The microstructure analysis revealed that the surface morphology of the microwave processed films become compact with respect to the processing time. The sheet resistance for microwave sintered silver films is in the range of 0.003 to $1.207{\Omega}/{\Box}$ where as the films fired at 750 and $850^{\circ}C$ showed the resistance of 0.009 and $0.003{\Omega}/{\Box}$ which can be comparable. The results revealed that the microstructure of the microwave sintered films has more uniform and compact surface than that of the conventionally fired films. The paper reports upon the preparation of silver thick film by screen printing technique and processing the same by microwave which also compared with the conventionally processed thick films.

• Journal of the Microelectronics and Packaging Society
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• v.21 no.4
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• pp.15-24
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• 2014

Recently, a variety of printing technologies, including ink jet, gravure, and roll-to-roll (R2R) printing, has generated intensive interest in the application of flexible and wearable electronic devices. However, the actual use of printing technique is much limited because the sintering process of the printed nanoparticle inks remains as a huge practical drawback. In the fabrication of the conductive metal film, a post-sintering process is required to achieve high conductivity of the printed film. The conventional thermal sintering takes considerable sintering times, and requires high temperatures. For application to flexible devices, the sintering temperature should be as low as possible to minimize the damage of polymer substrate. Several alternative sintering methods were suggested, such as laser, halogen lamp, infrared, plasma, ohmic, microwave, and etc. Eventually, the new sintering technique should be applicable to large area, R2R, and polymer substrate as well as low cost. This article reviews progress in recent technologies for several sintering methods. The advantages and disadvantages of each technology will be reviewed. Several issues for the application in R2R process are discussed.

• Journal of the Korean Ceramic Society
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• v.32 no.3
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• pp.331-340
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• 1995

Microwave (Hybrid) Heating (MHH) was used to oxidize and sinter Al-Al2O3 powder mixture. For 25 v/o Al specimen and 35 v/o Al specimen, the total processing to produce low-shrinkage reaction bonded alumina was carried out within 1 hour even though conventional furnace process took more than 10 hours. Compared with conventional fast firing process, MHH process increased more than 40% oxidation at the same temperature, and these high oxidation rates were thought to be caused by the surface ohmic current on Al particles.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.993-996
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• 2001

In the composition of 0.16BaO-0.15(Nd$\_$0.87/,Bi$\_$0.13/)$_2$O$_3$-0.69TiO$_2$$.$Glass [EG-2782] 3wt% addition sintered at 1080$^{\circ}C$, we could obtained microwave properties of dielectric constant $\varepsilon$$\_$r/= 80.1, quality factor Q ${\times}$ f = 810 (at 3.5 GHz]) and temperature coefficient of resonant frequency $\tau$$\_$f/ = -1.3 [ppm/$^{\circ}C$]

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.15 no.10
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• pp.870-875
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• 2002

Ba(Zn$_1$-xCox)TaO$_3$[BZCT] ceramics were Prepared by the conventional mixed oxide method. The ceramics were sintered at the temperature of 1450∼1550$\^{C}$ for 5 hr in air. The crystal structure of BZCT ceramics was investigated by the XRD. The microstructure of the specimens were observed by SEM. The structural properties of BZCT specimens were investigated as a function of composition and sintering temperature. All BZCT ceramics sintered over 1550$\^{C}$ were showed a polycrystalline complek perovskite structure without second phases and any unreacted materials. The density of BZCT (70/30) specimen sintered at 1550$\^{C}$ was 6.31g/㎤. In the case of the BZCT(70/30) ceramics sintered at 1550$\^{C}$ for 5 hours, dielectric constant, qualify factor and temperature coefficient of resonant frequency for microwave dielectrics application were a good value of 29, 16,468 at 10㎓ and -4.4 ppm/$\^{C}$, respectively.

• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.1009-1018
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• 1995

(Ti.Si)C composite powders were synthesized by SHS method using microwave energy. Compositional and structural characterization of the powder were carried out by using scanning electron microscopy and X-ray diffraction. The average particle size of the synthesized (Ti.Si)C composite powders was smaller than that of the starting materials. From the results of the temperature profile, combustion temperature and velocity were decreased with increasing Si molar ratio. With increasing C molar ratio combustion temperature and velocity did not change. (Ti.Si)C composite was sintered at 185$0^{\circ}C$ for 60 min by using hot-pressing with 30 MPa. The best properties were obtained from the sintered specimen whose composition was 1 : 1 : 1.9 molar ratio of Ti : Si : C. The sintering density, flexural strength and vickers hardness of the sintered body were 4.71 g/㎤, 423 MPa and 21 GPa, respectively.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1998.06a
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• pp.335-338
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• 1998

The effect of glass flit addition on microwave dielectric properties of BaTiO$_3$-3TiO$_2$ ceramic was studied. Addition of glass frit to this system obtained sintered sample below sintering temperature 105$0^{\circ}C$. At BaTiO$_3$-3TiO$_2$+ g1ass frit 3wt% + BaWO$_4$6 wt%m, this ceramic showed excellent microwave properties of dielectric constant 34, Q$\times$f 8,100, temperature coefficient of resonant frequency 4 ppm/$^{\circ}C$ .

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.405-408
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• 1997

The microwave dielectric properties of CuO and CdO addition of BiNbO$_4$ceramics were investigated. As the content of CdO increased, sintered density and quality factor is decreased. With increase in sintering temperature, the dielectric constant and quality factor is increased. In case of specimen sintered at 96$0^{\circ}C$ with 0.03 wt% CuO and CdO, the microwave dielectric properties obtained were dielectric constant of 41.2, quality factor (Q$\times$f) of 6, 500, temperature coefficient of resonant frequency of ppm/$^{\circ}C$.

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.42.2-42
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• 2003

• Proceedings of the Korean Ceranic Society Conference
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• 2003.04a
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• pp.115.2-115
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• 2003