本論文的目的有二。首先將整合犧牲層HSQ、擴散阻障層TaN、附著層Ta、銅之電化學電鍍、化學機械研磨等製造出銅導線鑲嵌結構；其次將利用微電子機械系統（MEMS）之技術在一介電材料覆蓋下剝除HSQ以製作出Air-gap結構，量測導線的電阻率並討論之。
犧牲層的部分，將HSQ（hydrogen silsesquioxane）與溶劑MIBK以2：1的比例混和後旋轉塗佈於蝕刻停止層氮化矽上，以350℃預烤3分鐘後形成之HSQ薄膜是很好的犧牲層材料。這是由於BOE溶液會從HSQ與其他介電材料間的介面開始蝕刻，而能方便而快速地剝起HSQ膜。100□厚的Ta與100□厚的TaN分別被用來當作附著層與擴散阻障層。在以銅之電化學電鍍填充溝槽後，以不傷害到樣品為原則，使用幾種不同的化學機械研磨參數以去除多餘的Cu／Ta／TaN膜，而完成銅導線鑲嵌結構。
接下來利用電漿輔助化學氣相沈積方式生長4000□氮化矽膜作為上方覆蓋的介電層，在氮化矽膜上沿著導線以CF4進行RIE開出長／寬為2.5μm／1.5倍導線線寬，間距為10μm之蝕刻窗口，其後以BOE溶液浸泡完成Air-gap銅導線鑲嵌結構。高解析度光學顯微鏡與SEM將被用來觀察此結構。
本實驗利用精密半導體參數分析儀HP 4156A配合探針座與導電式原子力顯微鏡（conductive AFM）兩種方式去量測電阻率，此兩種不同方式的量測結果將互相比較討論。

Two objectives are involved in the thesis. First, the fabrication of air-gap Cu damascene structure integrated with sacrificial layer HSQ, diffusion barrier TaN, adhesion layer Ta, electrochemical plating (ECP) of copper, and chemical mechanical polish (CMP) is demonstrated. Second, the air-gap formation by HSQ removal through a dielectric cap using MEMS technique is investigated, and the resistivity of copper lines is also studied.
HSQ with MIBK at ratio 2:1 was spun on etch stop layer SiNx. The HSQ film pre-baked at 350℃ for 3 minutes was a good sacrificial layer which could easily and quickly be removed from the interface with other dielectric materials by BOE solution treatment. 100□ Ta and 100□ TaN served as the adhesion and diffusion barrier layer, respectively. After trench filling by copper ECP, several CMP parameters were applied to remove unnecessary Cu/Ta/TaN without damaging the samples, and Cu damascene structure was done.
Then 4000□ SiNx deposited by PECVD was used as the dielectric cap. Etching windows with 1.5x line width / 2.5μm (window width / window length) on SiNx were formed by RIE with CF4 etchant and separated with 10μm along Cu damascene lines. The air-gap Cu damascene structure will be fabricated by BOE etching process. High resolution OM and SEM revealed the structure.
The resistivity of Cu lines was measured by HP 4156A with a probe station and Conductive AFM. The measurement results of the two approaches were discussed in the thesis.

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