本篇論文的重點在於反摻雜接面終結延伸應用於高電壓(>10kV)垂直型碳化矽元件的研究。根據模擬，單一區JTE結構的崩潰電壓對於JTE劑量變化相當敏感。反摻雜接面終結延伸區域為藉由佈植Ⅴ族元素在p型JTE，逐漸地減少JTE從內到外的濃度以形成多區域JTE的效果，使得電場被更均勻地分散，加寬佈植劑量的窗口和增加崩潰電壓。

本次實驗選用4H-碳化矽基板以及厚度為110µm、濃度為6.5x1014cm-3的磊晶層。以各種邊緣終結保護結構佈植不同的JTE的劑量，目標是達到崩潰電壓大於10kV以上。透過陽極歐姆接觸前的RIE製程改善，在順向偏壓10V時，電流密度可達到800A/cm2，反向特性方面，當反摻雜接面終結延伸長度為300µm時，6CD-JTE+OR的結構其崩潰電壓可以達到大於3000V，然而當反摻雜接面終結延伸長度為240µm時，其崩潰電壓不如模擬預期中的高，因此反摻雜結構在模擬和實驗之間的差異需要更進一步的查證。

Counter-doped junction termination extension (CD-JTE) for high-voltage (> 10kV) vertical SiC devices is investigated in this thesis. From simulation, breakdown voltage is very sensitive to the variation of JTE dose in SZ-JTE structure. In CD-JTE, N-type implant in the p-type JTE region, which reduces the effective JTE dose, can create a multi-zone effect. It makes electric field more uniformly distributed in the depleted JTE region to widen the process window of JTE dose and enhance breakdown voltage.

In experiment, a 110-µm-thick n-type epilayer with a doping concentration of 6.5x1014cm-3 was grown on a 4H-SiC substrate. Several edge terminations with different JTE doses were fabricated in order to achieve breakdown voltage greater than 10kV. The measured forward voltage drop at 800A/cm2 is 10V. In reverse characteristics, the breakdown voltage achieved with a 300µm wide 6CD-JTE+OR is more than 3000V. However, when CD-JTE width is reduced to 240µm, the breakdown voltage is not as high as predicted by simulation. The discrepancies between simulation and experiment require further examination.

中文摘要 I
Abstract II
第一章 序論 1
1.1 碳化矽的材料特性 1
1.2 功率元件的崩潰機制 3
1.3 文獻回顧 5
1.3.1 邊緣電場集中效應 5
1.3.2 邊緣終結保護結構 6
1.3 研究動機與論文大綱 7
第二章 元件模擬與設計 9
2.1 元件模擬 9
2.2 邊緣終結保護結構設計 9
2.2.1 接面終結延伸(JTE) 11
2.2.2 接面終結延伸附加浮動保護環(JTE+OR) 13
2.2.3 反摻雜接面終結延伸附加浮動保護環(CD-JTE+OR) 14
2.3 光罩設計 18
第三章 元件製程 20
3.1 對準記號 (Alignment Key) 24
3.2 平台隔離 (Mesa Isolation) 25
3.3 接面終結延伸離子佈植 (Junction Termination Extension Implant) 26
3.4 反摻雜佈植 (Counter-Doped Implant) 30
3.5 電性活化 (Electrical Activation) 31
3.6 保護層 (Passivation) 32
3.7 陽極歐姆接觸 (Anode Ohmic Contact) 32
3.8 陰極歐姆接觸 (Cathode Ohmic Contact) 33
第四章 實驗結果分析與討論 35
4.1 順向偏壓特性 36
4.2逆向偏壓特性 41
4.2.1 不同劑量下的統計結果 42
4.3 電容-電壓特性 46
4.4 反向回復特性 49
第五章 結論與未來展望 53
參考文獻 55

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