本論文之目的在於研究銅、擴散阻障層TaSix與低介電係數介質SiOC 之製程整合，並配合化學機械研磨製程完成銅/TaSix/SiOC damascene結構，探討其導線與導線之間漏電流傳導機制。
在低介電係數介質方面，以高密度電漿化學氣相沉積系統沉積SiOC薄膜，其介電係數經高頻電容-電壓曲線量測為2.77，並以傅立葉轉換紅外線光譜儀確認其薄膜之化學鍵結；另外也量測SiOC薄膜在300℃熱循環過程中之應力變化及熱循環後之薄膜殘餘應力大小。
擴散阻障層方面，以濺鍍方式沉積之TaSix薄膜，經由不同溫度下之薄膜導線電流-電壓曲線量測，從電阻率與溫度的關係圖中得到了電阻率隨溫度升高而下降的奈米顆粒特性；由歐傑電子顯微鏡之縱深分佈圖得知其原子組成比例約為Si/Ta=0.5。
將低介電係數介質SiOC、擴散阻障層TaSix、有電極電鍍銅配合化學機械研磨製程完成銅/TaSix/SiOC damascene平行導線結構，並在不同溫度下量測其導線與導線間之漏電流，由漏電流(lnJ)對電場(E1/2)的關係圖分析討論其漏電流傳導機制，從ln(J/T2) v.s. (1/T)之作圖得知銅/TaSix/SiOC damascene結構之漏電流傳導機制主要為Schottky emission並進一步由其fitting直線之斜率對E1/2作圖推算出擴散阻障層TaSix之能障高(barrier height)約為0.35 eV~0.38 eV。

The integration of copper, diffusion barrier nano-cluster TaSix and low-k dielectric SiOC were investigated. We fabricated diffusion barrier layer, nano-cluster TaSix, low-k dielectric SiOC, develop the processes integration for Cu metallization and investigated the conduction mechanism of line-to-line leakage current for damascene structure.
The dielectric constant of HDPCVD SiOC film obtained by high frequency C-V measurement was 2.77. Fourier transform infrared (FTIR) spectroscopy was performed in order to analyze the chemical structures of SiOC films. The residual stress and stress hysteresis of SiOC were measured during the thermal cycle of a temperature 300℃.
The I-V characteristics of nano-cluster TaSix film were performed at various temperatures(30℃~200℃). The resistivity of the film is decreasing as the temperature rises. Auger electron spectroscopy characterizes the chemical compositions of the thin barrier film.
The Cu damascene structures with diffusion barrier TaSix and low-k dielectric SiOC were fabricated. From leakage current measurements, the dominant conduction mechanism of the Cu/TaSix/SiOC damascene structure is Schottky emission. And the straight lines were fitted to the data points of Ln(J/T2) v.s. (1/T) plots. It also gave the information of the barrier height. The barrier height of TaSix/SiOC is about 0.35eV ~ 0.38eV.

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