本研究係發展一新穎構形之超穎材料(Metamaterial, MMT)，其在特定頻率下具有高電磁(Electromagnetic, EM)波吸收率；該材料可被應用在隱形科技以減少雷達截面積且可用於飛機及船舶的電磁波吸收器。本研究將討論在雷達的C及X頻段下，不同構形的超穎材料之吸收率。
首先，針對既有矩形超穎材料之構形進行修改及實測，以驗證數值模組之正確性。該材料成份為將銀(Ag)圖案披覆於聚酰亞胺(PI)的介電層上，其中介電層將被改為玻璃材料。本研究利用商業軟體COMSOL針對不同構形之超穎材料進行數值模擬；將探討正常入射電磁波之吸收率、工作頻率及S參數(S-parameters, S11及S21)等特性；其中，S11及S21分別反射係數及傳輸係數。此外，透過電子束蒸發器進行實驗，藉以驗證模擬之準確性；本研究發現其模擬與實驗結果相當吻合。
在數值模組驗證無誤之後，本研究另外針對其他數種不同的構形進行分析。對於特定頻率範圍之超穎材料的構形、幾何形狀、材料種類及各材料方向配置等特性進行設計，並探討其模擬結果。其中，可透過S參數(S-parameters, S11及S21)研究分析超穎材料性能；同時，藉由電磁場分佈情況以了解前述結構設計之吸收原理。透過研究可得到一種新的超穎材料構形，該結構在C和X頻率範圍時具有高吸收率及較大的頻帶寬度。

The main aim of this thesis is to develop a new metamaterial (MMT) design pattern with high electromagnetic (EM) wave absorption characteristics in radar frequency range, which can be applied in stealth technology for airplanes and ships. The frequency band of interest is C and X band of radar. Firstly, some modifications are done to the already existing rectangular metamaterial design pattern. The unit cell of existing design consists of silver (Ag) patterns coated on a dielectric layer of polyimide (PI). A dielectric layer is modified to be the glass. A numerical simulation of this design is performed by using the commercial software package of COMSOL. The absorptivity, operation frequency and S-parameters are investigated under the normal incidence of EM waves. In order to verify the feasibility of numerical module, experiments have been performed by using the E-beam coating machines. It is found that the experimental results agree closely with simulation results.
Secondly, a various MMT patterns are further designed with different geometry, shape and orientation at the desired frequency range and the results are carried out by numerical simulation. The S-parameters S11 (reflection coefficient) and S21 (transmission coefficient), are used to investigate MMT performance. The electromagnetic field distribution properties have been investigated in order to understand the absorption mechanism of the designed structure. A parametric study is performed for the selected design patterns in order to achieve high absorptivity and larger bandwidth. Eventually, a new metamaterial design pattern is selected with high absorptivity for C and X band of frequency regime.

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