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제1장 서론 15
제2장 실험 방법 24
제1절 하소 조건에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 합성 및 소결체 제조 24
0. 출발 물질 24
1. 하소 온도에 따른 소결체의 제조 24
2. K(Potassium) 추가 함량에 따른 소결체의 제조 24
3. 하소 단계에 따른 소결체의 제조 25
제2절 하소 및 소결 온도에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 합성 및 소결체 제조 26
제3절 시료 측정 방법 26
제3장 실험 결과 27
제1절 하소 조건에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 유전 특성 27
1. 하소 온도에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 유전 특성 30
2. K 추가 함량에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 유전 특성 36
3. 하소 단계에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 유전 특성 41
4. KCa₂Nb₃O₁₀ 시료의 추가 측정 결과 46
제2절 하소 및 소결 온도에 따른 KCa₂Nb₃O₁₀ 층상 페로브스카이트 소재의 유전 특성 57
제4장 결론 80
참고문헌 82
영문초록 90
Table 1. List of KCa₂Nb₃O₁₀ samples with different calcination temperature, K content, and number of calcination steps 27
Table 2. Area fractions of KCa₂Nb₃O₁₀, KNbO₃, Ca₂Nb₂O₇, CaNb₂O₆ phases, and pores in "K0-11", "K2-11" and "K0-5/11" 50
Table 3. List of KCa₂Nb₃O₁₀ samples for varying calcining and sintering temperatures 57
Table 4. Relative densities (in g cm⁻³) of KCa₂Nb₃O₁₀ samples for varying calcining and sintering temperatures 65
Table 5. Dielectric constants of KCa₂Nb₃O₁₀ samples at 25 ℃ for varying calcining and sintering temperatures 69
Table 6. Temperature Coefficient of Capacitance (TCC in %) of KCa₂Nb₃O₁₀ samples for varying calcining and sintering temperatures 74
Figure 1. Expected effect of Dion-Jacobson layered perovskite for dielectric materials 22
Figure 2. X-Ray Diffraction (XRD) patterns of KCa₂Nb₃O₁₀ (a) powder after calcining at different calcination temperature,... 31
Figure 3. (a) Room temperature dielectric constant (εr) and loss (tan δ) of KCa₂Nb₃O₁₀ bulk samples with different...[이미지참조] 34
Figure 4. X-Ray Diffraction (XRD) patterns of KCa₂Nb₃O₁₀ (a) powder of varying K content after calcining at 1100 ℃ for 10... 37
Figure 5. (a) Room temperature dielectric constant (εr) and loss (tan δ) of KCa₂Nb₃O₁₀ bulk samples with different K content...[이미지참조] 39
Figure 6. X-Ray Diffraction (XRD) patterns of KCa₂Nb₃O₁₀ (a) powder after calcining with different number of calcination... 42
Figure 7. (a) Room temperature dielectric constant (εr) and loss (tan δ) of KCa₂Nb₃O₁₀ bulk samples with different number of...[이미지참조] 44
Figure 8. Electron Backscatter diffraction (EBSD) (a) Image Quality (IQ) maps (b) Phase map of "K0-11" sample 47
Figure 9. Electron Backscatter diffraction (EBSD) (a) Image Quality (IQ) maps (b) Phase map of "K2-11" sample 48
Figure 10. Electron Backscatter diffraction (EBSD) (a) Image Quality (IQ) maps (b) Phase map of "K0-5/11" sample 49
Figure 11. Relationship of dielectric constant, KCa₂Nb₃O₁₀ average grain size and relative density of "K0-11", "K2-11"... 53
Figure 12. Cole-Cole plots of "K0-11", "K2-11", and "K0-5/11" samples measured with 1 Vrms at room temperature[이미지참조] 55
Figure 13. X-ray diffraction (XRD) patterns of KCa₂Nb₃O₁₀ powders calcined at (a) 900 ℃ (b) 1000 ℃, (c) 1100 ℃, and... 58
Figure 14. Scanning Electron Microscope (SEM) images of fractured KCa₂Nb₃O₁₀ bulk samples prepared via calcining(900 ℃... 61
Figure 15. (a) Relative densities of KCa₂Nb₃O₁₀-sintered samples for different calcining and sintering temperatures (b)-(d)... 64
Figure 16. Temperature-dependent dielectric constants (εr) and loss (tan δ) of KCa₂Nb₃O₁₀ samples calcined at (a) 900 ℃, (b)...[이미지참조] 68
Figure 17. Temperature Coefficient of Capacitance (TCC) of KCa₂Nb₃O₁₀ samples calcined at (a) 900 ℃, (b) 1000 ℃, (c) 1100... 73
Figure 18. Temperature-dependent AC Conductivities (σac) of KCa₂Nb₃O₁₀ samples calcined at 1100 ℃, followed by sintering at...[이미지참조] 77