晶粒尺寸對於鎳鐵薄膜的磁、光和電性之研究

本實驗是探討NiFe薄膜的結構、磁性、電性與光學性質。在製程方面是將NiFe薄膜被濺鍍在玻璃基板上，而其厚度為300 Å到1500 Å。其基板的溫度條件有室溫(RT)、後退火溫度(post-annealed, TA)150 ℃，1個小時及退火溫度250 ℃，1個小時。X光繞射儀(X-ray diffraction, XRD) 展示出NiFe薄膜為面心立方(face-centered cubic, FCC) 的結構型態。XRD也呈現出退火熱處理之樣品比室溫樣品有更好的結晶性。NiFe結晶性足藉由FCC (111)的繞射峰來觀察，所以退火溫度處理樣品比室溫的結晶性還要好。當使用穿透式電子顯微鏡(Transmission electron microscopy, TEM)探討微結構時，NiFe薄膜會產生FCC (111)的擇區繞射峰圖形，經由晶粒尺寸的計算，亦發現退火溫度熱處理對於晶粒尺寸有正面的影響，這與XRD的結果符合。至於NiFe薄膜在低頻下影響χac的最大值和共振頻率方面，本研究是使用變頻磁導分析儀(χac analyzer, XacQuan MagQu) 來量測NiFe薄膜的χac振幅，而測試頻率範圍介在10 Hz到25000 Hz。結果發現NiFe薄膜的χac振幅在退火熱處理和厚度的條件增加時有上升的趨勢，主要的原因是NiFe (111) 結構會有磁性結晶異向性(magneto crystalline anisotropy)，並會造成著最大χac值和共振頻率。同時在最大χac值和共振頻率狀態下會使自旋電子 (spin)的靈敏度提高。由基板三種熱處理，發現出在退火250 ℃ , 1個小時的條件下NiFe薄膜為1500 Å厚度下有最大χac值以及最佳共振頻率，分別為5.8和500 Hz。使用超微光學(Spectra Smart)用來測量薄膜的穿透率與反射率，結果發現:後退火處理促進了晶粒的生長，產生較大的平均晶粒尺寸，導致穿透率變小。然而電測量四點探針結果發現增加的電子遷移率降低了電阻率（ρ）和薄層電阻（Rs）。厚度為300 Å而後退火在250 ℃, 1個小時之樣品，有最大透射率為50％、ρ為110μΩcm、Rs為13Ω/cm2，因此300Å膜厚的鎳鐵薄膜具有良好的電氣和光學特性，經由退火溫度後會使NiFe薄膜的結構、磁性、光學、電性有正面影響，由此可見退火250 ℃， 1小時的溫度條件NiFe薄膜適合應用低頻底下的變壓器和感應器中。

關鍵字

none

並列摘要

In the work, the NiFe thin films of characterize were investigate, including structure, magnetic, electrical and optical properties. NiFe thin films were sputtered on a glass substrate with a thickness (tf) from 300 Å to 1500 Å under the following conditions: (a) substrate temperature (Ts) maintained at room temperature (RT), (b) post-annealing at heat annealing TA = 150 ℃ for 1 h, and (c) post-annealing at heat annealing TA = 250 ℃ for 1 h. X-ray diffraction (XRD) result demonstrates that the NiFe thin films have face-centered cubic (FCC) structure state. XRD also reveals that NiFe films are more crystalline with post-annealing treatment than RT. Moreover, it suggests that the FCC (111) texturing exists the NiFe crystallization from XRD result. Transmission electron microscopy (TEM) investigates the microstructure, It reveal film yielded a strong face-centered cubic (FCC) (1 1 1) selected-area-diffraction (SAD) pattern in NiFe films. Moreover, the grain size distribution was calculated by plain-view TEM result. Annealing temperature has a large grain size distribution, which is with XRD results consistent. The alternative-current susceptibility (χac) results show that the χac of NiFe thin films is increased as the post-annealing treatment and increased thickness. The NiFe (111) texture induces that the magneto crystalline anisotropy and demonstrates the maximum χac value with optimal resonance frequency (fres) effect, results in higher spin sensitivity at optimal fres. Therefore, the results of three conditions show that the maximum χac value and optimal fres of 1500 Å of NiFe thin film is 5.8 and 500 Hz at post-annealing TA = 250℃ for 1 h. Post-annealing treatment promoted the growth of grains, yielding a large average grain size, results in a small transmittance. However, electrical measurements revealed that increasing the electron mobility reduces the resistivity (ρ) and sheet resistance (Rs). At a thickness of 300Å with post-annealing 250 ℃, the optimal maximum transmittance is 50% ; the optimal ρ is 110 μΩ cm, and the optimal Rs is 13 Ω/cm2. According to above characterize of NiFe films condition is suitable for gauge sensor and transformer applications at low frequency range.

並列關鍵字

none

參考文獻

[38]. 磁量生技股份有限公司（MagQu Co., Ltd.），操作與維修手冊，2012年。

[20]. 陳淑貞，鈷薄膜在矽(100)表面的磁性觀測，國立台灣師範大學物理所碩士論文，國立台灣師範大學物理所碩士論文，1999年。

[19]. 陳宿惠，銀-鈷超薄膜在鉑（111）表面的磁性探討，國立台灣師範大學物理所碩士論文，1999年。

[1]. Y. S. Liu, J. C. Zhang, L. M. Yu, G. Q. Jia, C. Jing and S. X. Cao, “Magnetic and frequency properties for nanocrystalline Fe-Ni alloys prepared by high-energy milling method”, J. Magn. Magn. Mater., Vol. 285, 2005, pp.138-144.

[2]. K.H. Kima, J.H. Jeonga, J. Kima, S.H. Hanb and H.J. Kimb, “High moment and high frequency permeability Fe-B-N nanocrystalline soft magnetic films’’, J. Magn. Magn. Mater., Vol.239, 2002, pp.487-489.

國際替代計量

晶粒尺寸對於鎳鐵薄膜的磁、光和電性之研究

全文下載

主題瀏覽