多層基板結構關鍵射頻元件設計

Abstract

本論文旨在提出多層基板結構中射頻關鍵元件的設計與驗證。所使用之多層結構包含低溫共燒陶瓷（LTCC）及表面奈米處理之96%薄膜氧化鋁（Al2O3）板。首先，我們利用共振環結構方法來推估材料介電常數及損耗正切。接著設計微/毫米波頻段低溫共燒陶瓷轉接器，包含微帶線、帶狀線和層疊波導管之間的轉接設計。藉由圓形金屬柱來連接微帶線和帶狀線之間的接地金屬面，以及訊號線連接之用。並利用此圓形金屬柱將能量饋入至層疊波導管中。本論文的第三部分，是在薄膜氧化鋁板上設計平衡對不平衡轉接器。主要是以集總等效電路來取代四分之一波長傳輸線的方式來設計。最後，本論文將設計集總形式低溫共燒陶瓷三階交錯耦合帶通濾波器。因交錯耦合可提供電路輸出和輸入間兩條訊號路徑，藉由多重路徑而產生頻帶上的傳輸零點。

In this thesis, several RF key components have been designed and demonstrated in multi-layer structures such as the low-temperature cofired ceramic (LTCC) and the 96% Al2O3 substrate with surface naro-processing. First, the microstrip ring structure is used to find the electronic parameters of the LTCC. By comparing to the simulation and measurement results of a well-known substrate (RO 4003), the dielectric constant and loss tangent of the LTCC substrate are obtained. Next, transitions between LTCC microsrip line, stripline, and laminated waveguide at different layers are studied. Simulation and Measurement results show that good transition can be achieved by suitably designing the vias connecting the signal lines and those connecting the grounds. The third part of this thesis is to design a 5GHz balun in the thin-film substrate (Al2O3). The design is based on the lump element equivalent circuit of quarter-wave transmission line. Finally, this thesis design a LTCC lump-element three-order cross-coupling bandpass filter. The cross couplings give the signal two paths from input port to the output port, which cause transmission zeros at finite frequencies.