本實驗研究主要使用兩種方法合成磁電複合材料，其一使用熱壓法製備磁電複合塊材；其二使用磁控濺鍍法濺鍍磁電複合薄膜，其中研究的塊材與薄膜樣品，分別表示如下(i)BiFeO3-Ni0.5Zn0.5Fe2O4磁電複合塊材；(ii) BiFeO3-NixZn1-xFe2O4/LaNiO3/Si(x=0.3、0.5、0.7)磁電複合薄膜。
磁電複合塊材中的BiFeO3與Ni0.5Zn0.5Fe2O4分別是使用水熱法和固相燒結法製備，合成後的兩個材料再以熱壓法壓成複合塊材，此磁電複合塊材屬於2-2type對接方式，分析樣品後發現在熱壓前後複合塊材有內應變和晶粒大小的改變，最後造成此磁電複合塊材在零偏壓場下具有磁電係數αE=9.9mV/Oe．cm，在有外加DC偏壓磁場下具有磁電係數αE=11.7mV/Oe．cm。
磁電複合薄膜BiFeO3-NixZn1-xFe2O4 (x=0.3、0.5、0.7)利用雙靶共濺鍍的方式，沉積在LaNiO3/Si上，LaNiO3為底電極和緩衝層，此磁電複合薄膜屬於0-3type的對接方式，磁性量測後發現不同鎳鋅比例的磁電複合薄膜均具有明顯的磁交換偏置，且磁電複合薄膜BiFeO3-NixZn1-xFe2O4 (x=0.3、0.5、0.7)在當x=0.3時具有最大的飽和磁化量Ms=788.16emu/cc。磁電係數在零偏壓場下，當x=0.3時，在共振頻率下磁電係數有最大值αE=1531mV/cm．Oe；當x=0.5時，在共振頻率下磁電係數有最大值αE=979mV/cm．Oe，當x=0.7時，在共振頻率下磁電係數有最大值αE=511mV/cm．Oe。在有外加偏壓場的情況下當x=0.3時，在共振頻率下磁電係數有最大值αE=1787mV/cm．Oe；當x=0.5時，在共振頻率下磁電係數有最大值αE=1034mV/cm．Oe，當x=0.7時，在共振頻率下磁電係數有最大值αE=582mV/cm．Oe。接著探討BiFeO3-Ni0.3Zn0.7Fe2O4複合薄膜兩相比為62：38與51：49的磁電係數，兩相比為62：38的磁電複合薄膜之飽和磁化量和磁電係數均大於51：49。

Bulk samples and thin films of BiFeO3 (BFO)NixZn1-xFe2O4 (NZFO, x=0.30.7) composites were prepared by hot-pressing and RF magnetron sputtering, respectively. One of the aims was to study the effects of different Ni/Zn ratio on the magnetoelectric (ME) property of the BFONZFO composites. Thin films were grown on the LaNiO3 (LNO) buffered Si substrates by co-sputtering from two individual targets of BFO and NZFO. The results showed that the highest ME coefficients were achieved with the BFONZFO films of x=0.3, which were measured to be 1531 and 1787 mV/cmOe at 10 kHz without and with a DC magnetic bias of 1000 Oe, respectively. The ME coefficients were measured vertically from the conductive LNO buffer to film surface. The x=0.3 composite films also showed the highest magnetization of 788.2 emu/cc. For the bulk composites, NZFO thin disks were first synthesized by solid state sintering, while BFO disks were cold-pressed from the hydrothermal synthesized powders of a pure phase. The two disks were then hot-pressed together under the pressure of 4000 kg/cm2 at 200 C with silver epoxy painted at the interface. The ME coefficients of the bulk BFONZFO composites were far smaller than the films, which were typically in the order of 10 mV/cmOe. A part of the reason for the far smaller ME coefficient might be attributed to the inaccurate thickness used for the calculation. The effective thickness that had the contribution to the ME coupling might be far smaller than the sample thickness, which was typically 0.8 mm compared to the films of 300 nm.

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