本篇論文之主要研究重點在於發展高效率自動化製程技術電腦輔助設計（TCAD）技術以模擬微波及光電異質接面雙極電晶體（HBT）。隨著以異質接面雙極電晶體作為基本元件之射頻 (RF) 及光電 (optoelectronic)積體電路的普及化，晶片系統設計採用先進製程技術電腦輔助設計方法亦持續不斷的向前推進；對於現代積體電路設計者而言，發展出一套高效率元件模擬方法以自動萃取小信號等效電路模型參數之迫切性與日俱增。
　　本研究所提出的方法可精確的決定包括：外質電感以及本、外質電容在內的所有電路元件參數，並將此一創新技術成功的應用於數種不同的異質接面雙極電晶體元件結構之分析與特性探討。此一高效率自動化技術可解決許多傳統參數萃取方法所遭遇的問題，包括：額外測試結構之使用、特定基極電流下進行之順向偏壓測量、以及經驗導向之元件參數最佳化過程。值得一提的是，對於混合π等效電路元件之參數萃取完全以有系統、高效率的方式進行，包括：完全解析方法及以基因演算法 (genetic algorithm)為基礎的全域最佳化技術，其中所推導出的阻抗及導納公式乃將測量所得的微波s參數當作已知數據。為了進一步探討電路元件參數於不同偏壓狀況下的變化趨勢，異質接面雙極電晶體元件乃工作於廣泛之集極電流密度範圍，以評估其對於外質與本質電路參數所造成的影響。整個參數萃取過程中，整組具有物理意義的小信號模型參數依序地被萃取出來。為驗證本研究所提出的各種模型之有效性及精確度，曾將其應用於集極在上、pnp型砷化鋁鎵─砷化鎵異質接面雙極電晶體，射極在上、npn型硒化鋅─鍺異質接面雙極電晶體，以及矽─鍺異質接面雙極電晶體元件參數萃取。不論是直接測量、解析推導、數值模擬所得之s參數結果於整個工作頻率範圍內均達到相當一致的合理結果。由此符合理論預期之本、外質元件參數變化趨勢，顯示本論文所提出的先進等效電路模型將可被嵌入自動化的電路模擬器，以便應用於微波及光電積體電路之模擬設計。
　　本論文之組織編排方式說明如下：
第一章─整體研究內容簡介。
第二章─當代各國研究單位發表之元件模擬及參數萃方法詳細比較說明。
第三章─對於與研究相關的異質接面雙極電晶體之元件物理、結構、工作原理作精要敘述。
第四章─描述應用於異質接面雙極電晶體元件分析之小信號混合π等效電路模型，涵蓋低頻導納及高頻阻抗矩陣公式推導過程。
第五章─詳細闡明完全解析參數萃取步驟應用於集極在上型HBT之過程。
第六章─呈現完全解析參數萃取獲致之結果，並以定性定量方式評估之。
第七章─提出以基因演算法配合一般化的解析等效電路元件參數矩陣公式之全域數值最佳化模擬技術，將其應用於微波及光電HBT。
第八章─作出結論，並提出對於未來持續研究工作之展望。

　　As system-on-chip (SoC) designs using technology computer-aided-design (TCAD) techniques constantly advance with the popularization of RF integrated-circuits (RFICs) and optoelectronic-integrated-circuits (OEICs) applications, based on heterojunction bipolar transistors (HBTs), the efficient device-modeling methodology for automatic extraction of small-signal equivalent-circuit parameters is increasingly crucial for modern IC designers.
　　In this study, all of the circuit elements, including extrinsic inductances as well as intrinsic and extrinsic capacitances, are determined unambiguously and the innovative techniques have been successfully applied to analysis/characterize several HBT structures. The efficient techniques are capable of resolving some problems encountered among conventional extracting methods that are the use of additional test structures, forward-biased measurements at specific bias conditions, and empirical optimization process. Above all, the hybrid-π equivalent-circuit elements are extracted in a systematic and efficient way, including pure analytic method and genetic-algorithm (GA)-based generalized optimization technique, from impedance and admittance formulation on the basis of measured S-parameters.
　　To investigate the bias dependence, the extrinsic and intrinsic circuit elements are evaluated under a variety of biasing conditions. The model parameters are sequentially derived during the extraction process yielding a full set of physically meaningful values. The validity of the proposed model has been explored on pnp collector-up AlGaAs-InGaAs HBTs, npn emitter-up ZnSe-Ge HBTs, and SiGe HBTs. Good coincidence among directly-measured, analytically-derived, and numerically-simulated S-parameters is observed across the entire frequency range of operation. Consistent extracted trends indicate that the advanced equivalent-circuit model is suitable to be implemented in automated circuit simulators with application to microwave and optoelectronic circuit simulations.

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