臺灣博碩士論文加值系統

摘要
本篇論文在於對非晶矽/鉭/氧化矽/矽結構，發展出以電化學方式對非晶矽進行無電極電鍍置換沉積銅種子層。我們藉由改變非晶矽厚度由200A∼400 A;及改變置換液HF濃度由6%∼8%來找出置換銅種子最佳情況。首先透過掃瞄式電子顯微鏡、α-step、四點探針、歐傑電子質譜儀及二次離子質譜儀分析來瞭解置換銅種子層置換沈積率、電阻率及縱深成份元素分析；另外也藉由低略角X光粉末繞射分析（GIA XRD）來瞭解銅膜晶向並探討置換時銅膜剝落附著力變差的原因是由於TaOx的產生。而在經過通N2氣中RTA快速升溫退火溫度400℃、時間400sec之後，銅種子層電阻率可達28.6μΩ-cm。之後再配合於有電極電鍍，藉由量測儀器上的分析觀察來瞭解其電鍍銅膜晶向、熱穩定性以及定性上的附著力測試；在非晶矽厚度增加到400A時保護底下Ta減少氧化除對銅膜附著力有增強的效果，加上經過溫度400℃、時間400sec 的RTA 更增強了Cu/Ta之間附著力，其附著力最高可達到186.84 Kg/cm2，有助於日後配合後段製程化學機械研磨機（CMP）上之整合。最後再由SEM觀察其填充高深寬比孔洞之能力：當電漿輔助化學氣相沉積非晶矽厚度到300A以上時，置換銅種子層已漸漸能夠填充高深寬比孔洞，對置換非晶矽厚度300A時;其銅種子層可填充進0.11μm最小孔徑，深寬比為1.8；而非晶矽厚度400A;其置換銅種子層也可達到填充孔徑0.11μm，深寬比為2的孔洞。

Abstract
We developed the electrochemical displacement method of Cu seed-layer formed by replacing the amorphous-Si on Ta/SiO2/Si structure. The thickness of amorphous-Si varing from 200 Å ~ 400Å and HF concentration changing from 6% ~ 8% were performed in order to find the best condition for Cu seed layer deposition. The deposition rate, resistivity and depth profile of atomic composition for the displaced Cu seed layer were studied from measurement of SEM,α-step, Four Probe Point, Auger and SIMS. In addition, it was owing to TaOx resulting in poor adhesion when we discuss Cu films peeling by GIA XRD. After the rapid thermal annealing at temperature 400℃ for 400sec in N2 ambient , the resistivity of Cu seed layer is 28.6μΩ-cm. After electroplating Cu films, the grains texture, thermal stability and adhesion were detected by XRD, SIMS and 3-M scotch type test or adhesion testing. Subsequently, the thick a-Si layer protects Ta from oxidation, it does increase Cu/Ta adhesion, and RTA at temperature 400℃ for 400sec in N2 ambient will also improve ability of adhesion. Finally, the ability of filling vias with high aspect ratio was investigated. the seed layers can fill 0.11μm with aspect ratio 1.8 for a-Si 300Å and aspect ratio 2 for a-Si 400 Å.

目錄
第一章 緒論…………………………………………………………….1
第二章 有電極電鍍銅沈積原理…………………………………....3
2-1 電解反應……………………………………………….3
2-2 金屬的電極電位……………………………………….3
2-3 鍍膜結構……………………………………………….5
2-4 有電極電鍍銅鍍液組成 ……………………………....6
第三章 矽上置換銅種子層沈積原理……………………………....7
3-1 矽上置換銅種子層基本機制………………………….7
3-2 矽上置換銅種子層溶液組成………………………….7
第四章 量測原理……………………………………………………9
4-1 四點探針……………………………………………….9
4-2 X光粉末繞射分析…………………………………….10
4-3 掃描式電子顯微鏡分析 ……………………………....12
4-4 二次離子質譜儀分析………………………………….14
4-5 歐傑電子能譜分析………………………………….16
4-6 電容-電壓曲線量測 …………………………………...17
4-7 薄膜附著力測試……………………………………….19
4-8 原子力探針顯微鏡…………………………………….19
第五章 實驗………………………………………………………....20
5-1 樣品製作……………………………………………….20
GroupA 非晶矽/鉭結構上置換銅種子層…..………..20
GroupB 置換銅種子層配合有電極電鍍銅………….24
GroupC 應用於有電極電鍍填充孔洞…….………….25
5-2 物性量測……………………………………………….27
5-2.1 片電阻………………………………………27
5-2.2 X光粉末繞射儀……………………………27
5-2.3 掃描式電子顯微鏡…………………………27
5-2.4 歐傑質譜儀 ………………………………27
5-2.5 二次離子質譜儀……………………………27
5-2.6 高頻電容-電壓曲線量測…………………...28
5-2.7 薄膜附著力測試…………………………….28
5-2.8 原子力探針顯示器……………………………28
5-3各製程詳細步驟………………………………………….29
第六章 結果與討論 ………………………………………………….32
6-1 置換銅種子層薄膜分析……………………………………..32
6-1.1 沈積率 ……………………………………………..32
6-1.2 銅種子薄膜厚度量測 ………………………………..33
6-1.3 電阻率………………………………………………..33
6-1.4 置換銅種子層表面grains生長情況………………..37
6-1.5 AFM薄膜表面roughness分析……………………...37
6-1.6 歐傑電子質譜儀分析………………………………..37
6-1.7 小角度X光粉末繞射儀分析………………………..38
6-2 配合有電極電鍍銅製程整合………………………………49
6-2.1 電阻率……………………………………………….49
6-2.2 XRD粉末繞射儀分析………………………………49
6-2.3 薄膜附著力測試…………………………………….49
6-2.4 縱深分佈量測………………………………………49
6-2.5 C-V量熱穩定性……………………………………50
6-3 應用於填充孔洞瞭解其填充能力………………………...54
6-3.1 置換銅種子層應用於填充孔洞……………………54
6-3.2 配合應用於有電極電鍍……………………………55
第七章 結論………………………………………………………….62
參考文獻……………………………………………………………...64

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