本論文設計並研製了一台切換頻率約400 kHz且最高功率達2.5千瓦的遠程電漿源。遠程電漿源已被廣泛應用於晶片製造業中，除了可用於進行沉積與蝕刻以外，亦可應用於反應腔體內部的清潔。當反應腔體內壁堆積了過厚的矽種膜，矽種膜會剝落而污染晶圓，破壞原有的製程步驟。因此週期性的對反應腔體內部進行清潔為不可或缺的流程之一。遠程電漿源於反應腔外部產生可與矽種膜反應之電漿後，通過管線將電漿通入反應腔中，使電漿與矽種膜反應生成為矽種氣體後再將之排出反應腔外，即可完成自動化的清潔流程。本研究所聚焦研究之遠程電漿源，即為使用NF3氣體產生氮氣電漿之乾式清潔電漿源。
產生電漿的過程主要分為兩個步驟：點火與持弧。「點火」為一開始使用電容性放電電漿的形式，以高壓解離墮性氣體如氬氣，進而產生初始的自由電子。而後再供給腔體足夠高的電流及功率，採用電感性耦合電漿的方式，使腔體內的氮氣電漿能持續產生即為「持弧」。而本研究中分別設計了一個5千伏容性負載的高壓輸出逆變器作為「點火器」，用於初始的點火步驟，以及一個2.5千瓦定電流30安培輸出的高功率逆變器作為「維持器」，用以維持不同氣體流量下的氮氣電漿持續產生。
為了設計兩台作為不同用途的逆變器，本研究將電漿負載進行了建模。由於電漿源腔體的設計掌控在其他研究者手中，在資訊以及設備有限的情況下，本研究根據灰箱研究的方式，將電漿載轉換成為等效之RLC負載。並且不僅不需使用傳統電漿侵入式量測設備蘭姆探針，亦將氮氣氣體流量以及操作頻率這兩個影響等效負載關鍵因素的變動納入建模考量。
根據所建模之等效電漿負載，作為高壓點火器的半橋諧振逆變器，以及作為高功率維持器的全橋諧振逆變器皆設計並研製。本研究採用瑞薩RX62T做為核心之數位處理器，並做為遠程電漿源之控制器，不僅能控制整個點火到維持的功率輸出流程，亦做為過壓過流保護之用途，以及控制逆變器使能穩定輸出。
雖然實際的電漿產生過程中，由於氣體流動以及化學反應等難以控制速度的特性，不會有快速切載的控制需求，但本研究依然設計了回授補償，並且實際使用等效RL負載，進行了單台高功率逆變器的切載測試。而考量到未來電漿源功率擴充之可能性，本研究亦針對兩台高頻高功率逆變器的並聯使用時之小訊號模型，進行建模並設計控制迴路。其設計結果亦進行了切載模擬並得到良好的控制效果，可做為未來此類高頻逆變器並聯研究之參考。
最後，本研究所設計之遠程電漿源，亦實際使用氮氣與氬氣，進行不同氣體流量下的電漿產生測試，並將結果呈現於論文中。
本論文的主要貢獻如下:
 所設計之遠程電漿源可於不同氮氣流量下穩定輸出電漿。
 點火器與維持器完全獨立分開的設計有助於日後維修替換、功率提升甚至是應變不同點火電壓的氣體應用。
 所採用之等效電漿負載建模方法，有別於傳統電漿負載量測方式，不僅不需破壞腔體進行侵入式量測，亦不需要昂貴的特殊設備即可進行。
 所建模之等效電漿負載，將隨著流量以及切換頻率，而產生之動態變化納入考量，並結合進逆變器的設計過程中。

In this dissertation, a remote plasma source with a switching frequency of about 400 kHz and a maximum power of 2.5 kW is designed and implemented. The remote plasma source has been widely used in the wafer fabrication industry, not only for deposition and etching, but for cleaning the interior of the reaction chamber. When too much silicon film accumulates on the inner wall of the reaction chamber, the silicon film will flake off, contaminating the wafer and disrupting the initial process steps. Therefore, periodic cleaning of the reactor chamber is an essential process. The remote plasma source generates plasma outside the reactor chamber that can react with the silicon film. Then, it passes the plasma into the reactor chamber through the pipeline. The plasma reacts with the silicon film to form silicon gas and then discharges it out of the reactor chamber; thus, completing the automatic cleaning process. The remote plasma source in this research is a dry-cleaning plasma source using NF3 gas to generate nitrogen plasma.
The plasma generation process is divided into two main steps: ignition and sustainment. "Ignition" is the beginning of the use of capacitive discharge plasma in the form of high-voltage dissociation of inert gases, such as argon gas to produce the initial free electrons. And then, provide the chamber with enough current and power, using inductive coupling plasma, so that the chamber of the nitrogen plasma can continue to generate; that is "sustainment." In this study, we designed a 5 kV capacitive load high voltage output inverter as the "igniter" for the initial ignition step, and a 2.5 kW constant current 30 A output high power inverter as the "sustainer" to maintain different gas flow rates under the nitrogen plasma continued to generate.
In order to design two inverters for different applications, the plasma load was modeled in this study. Since the plasma source chamber design is in the hands of other researchers, this study converts the plasma load into an equivalent RLC load based on a grey-box study with limited information and equipment. In this study, a conventional plasma intrusive measurement equipment Langmuir probe is not required. The variation of two key factors affecting the equivalent load, nitrogen gas flow-rate and operating frequency, are taken into account in the modeling.
Based on the modeled equivalent plasma load, a half-bridge resonant inverter as a high-voltage igniter and a full-bridge resonant inverter as a high-power sustainer were designed and developed. In this study, the Renesas RX62T is used as the core digital processor for the remote plasma source controller. It controls the whole power output process from ignition to sustainment, serves as an over-voltage and over-current protection, and controls the inverter for stable output.
Although the actual plasma generation process is challenging to control the speed due to gas flow and chemical reaction characteristics, there is no need for fast step load change control. However, this study designed the feedback compensation and used the equivalent RL load to conduct step load change testing. Considering the possibility of future power expansion, this study also models and designs the control loop for the small-signal model of two high-frequency high-power inverters in parallel. The design results are also simulated for step load change. Control results are obtained, which can be used as a reference for future research on parallelizing such high-frequency inverters.
Finally, the remote plasma source designed in this study was tested with nitrogen and argon gas at different gas flow rates, and the results are presented in the dissertation.
The main contributions of this dissertation are briefly presented as follows:
 The proposed remote plasma source can output stable plasma at different nitrogen flow rates.
 The completely separate design of the igniter and sustainer facilitates future maintenance replacements, power upgrades, and even applications with different ignition voltages.
 The equivalent plasma load modeling method differs from the traditional plasma load measurement method. It does not require breaking the chamber for intrusive measurements and expensive special equipment.
 The modeled equivalent plasma load considers the dynamic changes with flow rate and switching frequency, and is integrated into the design process of the inverter.

中文摘要 i
ABSTRACT iii
ACKNOWLEDGMENTS vi
TABLE OF CONTENTS viii
LIST OF FIGURES xii
LIST OF TALBES xix
LIST OF ABBREVIATION xxi
CHAPTER 1 INTRODUCTION 1
1.1 Background and Motivation 1
1.1.1 Plasma 1
1.1.2 Remote Plasma Source 3
1.2 Review of Previous Work 6
1.2.1 Discharge Type of RPS 6
1.2.2 Power Supply of RPS 9
1.2.3 Plasma Equivalent Impedance Measurement Method 13
1.2.4 Control Review 14
1.3 Dissertation Outline 15
CHAPTER 2 EQUIVALENT REMOTE PLASMA LOAD 17
2.1 Ignition and Sustaining Plasma in Proposed RPS 18
2.1.1 Plasma Generation Principle 18
2.1.2 Capacitive Discharge 19
2.1.3 Transformer-Coupled Plasma (TCP) Source 19
2.2 Equivalent Impedance of Plasma Load 21
2.3 Traditional Plasma Load Acquiring Method: Langmuir Probe 22
2.3.1 Measurement Method of Langmuir Probe 23
2.3.2 Process of Obtaining Plasma Equivalent Impedance Using Langmuir Probe Measurement Results 24
2.4 Equivalent RLC Load Without Intrusive Measurement 26
2.4.1 Key Specification Identified for Preliminary Inverters Design 28
2.4.2 Preliminary HB-LCC Inverter Design of Ignitor for Modeling 30
2.4.3 Preliminary FB-LC Inverter Design of Sustainer for Modeling 31
2.4.5 Equivalent Impedance of Plasma Load for Sustainer 34
2.4.6 Equivalent Impedance of Plasma Load for Ignitor 39
2.5 Summary 39
CHAPTER 3 DESIGN OF RPS SUSTAINER AND IGNITOR 41
3.1 Overview of the Remote Plasma System 41
3.2 Ignitor Design 44
3.2.1 The Operating Principal of Frequency Modulated HB LCC Resonant Inverter 44
3.2.2 Analysis of LCC Resonant Tank 47
3.2.3 Resonant Tank Design of HB-LCC Inverter as Ignitor of RPS 51
3.2.4 Simulated and Experimental Results 53
3.3 Sustainer Design 55
3.3.1 The Operating Principal of Frequency Modulated FB-LCL-T Inverter 56
3.3.2 Analysis of LCL-T Resonant Tank 59
3.3.3 Design of FB-LCL-T Inverter as Sustainer 62
3.3.4 Simulated and Experimental Results 64
3.4 Summary 68
CHAPTER 4 CONTROL STRATEGY FOR RPS INVERTERS 70
4.1 Phasor Model of Resonant Inverter 70
4.1.1 Modified Phasor Transformation 71
4.1.2 Modified Phasor Dynamic Model 72
4.1.3 Verification of Phasor Dynamic Models with Switching Level Simulation 77
4.2 Control of Individual Sustainer Inverter Modules 84
4.2.1 System Setup 85
4.2.2 Controller Design of Individual Inverter 86
4.2.3 Simulated Results 92
4.2.4 Experimental Results 97
4.3 Control of Sustainer Inverter Modules Operated in Parallel 101
4.3.1 Circulating Current Analysis 101
4.3.2 Small Signal Modeling 105
4.3.3 Controller Design of Paralleled Inverter 106
4.3.4 Simulated Results 117
4.4 Summary 125
CHAPTER 5 PLASMA GENERATION EXPERIMENT 126
5.1 System Configuration and Implementation of the RPS System 127
5.2 Plasma Generation Process 129
5.2.1 Flowchart and Timing Sequence 129
5.2.2 Ignition Process 131
5.2.3 Sustaining Process 133
5.3 Summary 139
CHAPTER 6 CONCLUSIONS AND FUTURE RESEARCH 140
6.1 Conclusions 140
6.2 Future Research 142
References 144
VITA 151
PUBLICATIONS 151

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