在以Pd為電極，結晶態的TiO2為介電層的金屬-絕緣層-金屬 (metal-insulator-metal, MIM) 電容中，可以透過氮氣電漿處理鈍化因晶界引起的缺陷來減小漏電流；繼續將Ge奈米晶粒 (nanocrystals, NCs) 放入結晶態TiO2中，可以再將漏電流抑制約1000倍，在-1 V時達到了4.610-7 A/cm2，同時也保持了極高的電容密度25.2 fF/μm2；奈米晶粒在此處的作用為捕捉電子，引發庫倫阻斷效應 (Coulomb blockade effect) 或是形成內建電場來補償外加電場，達到減小漏電流的目的。
本篇論文中的MIM電容還有一些令人感興趣的優點，像是小的溫度電容係數 (temperature coefficient of capacitance, TCC) 88 ppm/℃，低的介電消散角度 (dielectric loss tangent) 0.02，以及令人滿意的可靠度，在2.5 V加壓的情況下十年後電容變化率為1.74%，此MIM電容不但擁有卓越的表現，同時此低漏電流/高可靠度的MIM電容對應用於下個世代的電路中具有極大的潛力。

With Pd as electrode, crystalline TiO2-based MIM capacitors were found to demonstrate improved leakage current by adopting nitrogen plasma treatment due to the passivation of grain boundary related defects. Through the introduction of Ge nanocrystals into crystalline TiO2, the leakage current can be further suppressed by near 3 orders to be 4.610-7 A/cm2 at -1 V while maintaining high capacitance density of 25.2 fF/μm2. The major role of nanocrystals is to trap electrons and then suppress leakage current by inducing Coulomb blockade effect or building an internal field to compensate the applied external field. The MIM capacitors developed in this work also display other intriguing features in terms of small TCC of 88 ppm/℃, low loss tangent of 0.020 and satisfactory capacitance change of 1.74 % after 10-year operation under 2.5 V stress. The MIM capacitor technology not only exhibits the prominent performance which is advantageous over other TiO2-based capacitors, it also possesses the capability to implement low-leakage/high-reliability MIM capacitors for next generation circuits.

摘要.............................................................................................................................................i致謝..........................................................................................................................................iii目錄...........................................................................................................................................iv圖目錄...................................................................................................................................vii表目錄.....................................................................................................................................x

第一章 序論............................................................................................................................1
1-1 背景介紹............................................................................................................1
1-2 MIM電容的結構與特性..................................................................................2
1-3 MIM電容的應用..............................................................................................3
1-4 研究動機............................................................................................................4
1-5 論文結構............................................................................................................4

第二章 電性量測與文獻回顧…………………………………………………..…............10
2-1 電容的電性量測……………………………………………..………...…....10
2-1-1漏電流…….……………...……..………………...……………...…….10
2-1-2 漏電機制 (leakage mechanisms)……………………………………..11
2-1-3 SILC (stress induced leakage current)………………………………..13
2-1-4電容密度與溫度電容係數………….………………………………....13
2-1-5可靠度分析 (reliability)…………………………………...…………..15
2-1-6消散角度 (loss tangent)…………………………….………………….16

2-2 文獻回顧………………………………………………………………….16
2-2-1 Reduction of Leakage Currents with Nanocrystals.................................16
2-2-2 MIM Capacitors with Crystalline-TiO2/SiO2 Stack.................................17
2-2-3結論…………………………………………………………………..18

第三章 實驗流程..................................................................................................................28
3-1 元件製程..........................................................................................................28
3-1-1 晶片清潔與基板製程……………………………………………...…28
3-1-2 下電極堆疊…………………………………………………………..29
3-1-3 介電層堆疊與處理...............……………..…………………………..29
3-1-4 上電極堆疊………………………………….………………………30
3-2 元件量測…..…………………………………………………………………30

第四章 結果與討論…………………………………………………………………..35
4-1 電容對電壓 (C-V) 特性曲線……………………………………………..35
4-2 電流對電壓 (I-V) 特性曲線……………………………………………...36
4-3 漏電流機制………………………..…………………………………………37
4-4溫度電容係數 (TCC)………………………………………………………..38
4-5 介電層消散角度 (dielectric loss tangent)…………………………………38
4-6 SILC……..................………………………………………………………..39
4-7 可靠度分析…………………….………………….….……………………39
4-8 元件比較……………………………………………………………………..40

第五章 結論與未來展望…………………………………………………………………..51
參考文獻……………………………………………………………………………………. 53

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第五章
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