• Journal of the Microelectronics and Packaging Society
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• v.28 no.1
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• pp.39-46
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• 2021

The quantitative measurement of interfacial adhesion energy (Gc) of multilayer thin films for Cu interconnects was investigated using a double cantilever beam (DCB) and 4-point bending (4-PB) test. In the case of a sample with Ta diffusion barrier applied, all Gc values measured by the DCB and 4-PB tests were higher than 5 J/㎡, which is the minimum criterion for Cu/low-k integration without delamination. However, in the case of the Ta/Cu sample, measured Gc value of the DCB test was lower than 5 J/㎡. All Gc values measured by the 4-PB test were higher than those of the DCB test. Measured Gc values increase with increasing phase angle, that is, 4-PB test higher than DCB test due to increasing plastic energy dissipation and roughness-related shielding effects, which matches well interfacial fracture mechanics theory. As a result of the 4-PB test, Ta/Cu and Cu/Ta interfaces measured Gc values were higher than 5 J/㎡, suggesting that Ta is considered to be applicable as a diffusion barrier and a capping layer for Cu interconnects. The 4-PB test method is recommended for quantitative adhesion energy measurement of the Cu interconnect interface because the thermal stress due to the difference in coefficient of thermal expansion and the delamination due to chemical mechanical polishing have a large effect of the mixing mode including shear stress.

• Korean Journal of Environmental Agriculture
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• v.22 no.4
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• pp.255-260
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• 2003

Silicon is known to accumulate in plants and results in greater resistance to diseases and insect pests. In this study, we investigated the effect of silicate fertilizer applied in soil on the development of powdery mildew of oriental melon. Oriental melon seedlings of four-leaf stage were transplanted and grown in a plastic film house. Silicate fertilizer was applied to maintain soil available $SiO_2$ level of 200 mg/kg one week before transplanting. Fungicide triflumizol was sprayed three times; one, two, and three weeks after transplanting. Sphaerotheca fuliginea was inoculated 2 weeks after transplanting. The number of infected leaf and the number of fungal colony in leaves were measured one, two, and three weeks after the inoculation. Three weeks after the fungal inoculation, in the treatment of fungicide triflumizol. infected leaf numbers and number of colony per leaf were reduced by 10 and 58%, respectively. In the silicate fertilizer treatment, infected leaf numbers and numbers of colony per infected leaf were suppressed only by 6 and 16%, respectively, and the efficacy was lower than that of the fungicide triflumizol. The combined treatment of silicate fertilizer and the fungicide suppressed powdery mildew more effectively, and infected leaf numbers and numbers of colony per leaf were reduced by 31 and 80%, respectively. These results indicate that although silicate fertilizer itself is not much effective in the suppression of powdery mildew, it can significantly enhance the efficacy of the fungicide.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.32 no.1
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• pp.7-11
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• 2022

Recently, Hanmi Gemological Institute & Laboratory (HGI) had an opportunity to examine 5 transparent synthetic moissanite. The round brilliants ranged from 0.93 to 0.96 ct and had a colorless, pink, yellow, blue, and red color. Advanced testing results, including Fourier-transform infrared (FTIR) and Raman spectroscopy, identified all the specimens as synthetic moissanite. Under the microscope, all samples except the colorless were confirmed to be a synthetic moissanite coated with a colored film. EDXRF chemical analysis detected very weak X-ray fluorescence peak characteristics of Ca, Ti, and Co in the colored samples. These features were not detected in the colorless sample. Raman spectroscopy investigation was unable to detect the 1332 cm^-1 (produced by sp³ bonding of carbon atoms) or the ~1550 cm^-1 (produced by graphite-related sp² bonding) peak in the colorless sample. The SEM image of the colorless sample showed no indication of a coating. The TEM image of the colorless sample revealed the presence of a 3~8 nm thick layer on the moissanite. Moreover, from the corresponding STEM Z-contrast image combined with the energy-dispersive X-ray spectroscopy (EDX) line profiles and EDX elemental maps, this layer was estimated to be carbon, silicon and oxygen.