ITO 擴散阻障層直接電鍍銅之研究

Study of Cu film directly electroplating on Induim Tin Oxide diffusion barrier

簡竹模(Chu-Mo Chien)

指導教授 ： 張益新

共同指導教授 ： 謝淑惠(Shu-Huei Hsieh)

國立虎尾科技大學/電機資訊學院/光電與材料科技研究所/碩士(2008年)

摘要

本研究先以真空磁控濺鍍方式在矽基材上沉積奈米尺寸(10 nm &
5 nm)的銦錫氧化物薄膜(Indium Tin Oxide, ITO)，再以電鍍方式，
在銦錫氧化物薄膜上沉積銅金屬層，接著以快速退火爐(Rapid
Thermal Annealing, RTA)在真空與氬:氫(95:5)的氣氛下進行
300~800 ℃的熱處理，持溫五分鐘。所有試片分別以四點探針
(four-point probe)、X 光繞射儀(XRD)、掃描式電子顯微鏡及穿透
式電子顯微鏡(TEM)等儀器來分析ITO 阻障層之片電阻值、相、表面
和界面微觀結構以瞭解真阻障效果。
為改善電鍍銅膜與ITO 薄膜間之剝離現象，在ITO 薄膜上再以真
空磁控濺沉積一層釕(Ru)金屬層來改善電鍍銅膜與ITO 鍍膜間的結
合性；接著以無電鍍方式在電鍍銅膜上沉積CoWP 薄膜做為覆蓋層，
以防止電鍍銅膜在熱處理溫度作用下產生聚集。
最後以真空濺鍍及無電鍍在ITO/Si 沉積銅金屬層，藉此比較電
鍍、無電鍍及真空磁控濺鍍三種方式所沉積之銅膜對ITO 阻障層有何
種影響。實驗結果顯示電鍍及無電鍍所製備之Cu/ITO/Si 試片可有效
抵擋銅原子擴散達600 ℃；以真空磁控濺鍍所製備之試片，其失效
溫度為700 ℃。

關鍵字

電鍍銅 ； 銦錫氧化學 ； 擴散阻障層

並列摘要

In the research, the effect of electroplating Copper (Cu) film on
Indium Tin Oxide (ITO) diffusion barrier was studied, improved by
additional treatments and finally compared with electroless Cu and
magnetron sputter Cu film.
First, silicon (Si) substrate was deposited ITO thin film with 10 and
5 nm thickness by Magnetron Sputter in vacuum, separately, then electro
Cu film was electroplated onto it, and annealed at 300 to 800 ℃ for 5 min
in rapid thermal annealing (RTA) furnace in vacuum and atmosphere of
Ar and H2 with a volume ratio of 95:5, respectively. The microstructure,
phase, and sheet resistance of various Cu/ITO/Si sample were observed
and measured by transmission electron microscopy (TEM), scanning
electron microscopy (SEM), X-ray diffractometer (XRD), and four-point
probe.
To improve the interface between Cu and ITO film, a seed layer of
ruthenium (Ru) film with 5 nm thickness was coated onto ITO film by
Magnetron sputter before electroplating Cu process. And to inhibit Cu
agglomeration in annealing process, a capping layer of Co-W-P film was
electroless plated onto Cu film.
Finally, the influence of Cu film Cu/ITO/Si by electroplating,
Electroless plating and Magnetron Sputtering process on ITO diffusion
barrier was inrestigated. The results show that Cu film in Cu/ITO/Si,
which was deposited by electroplating and electroless plating process
could hinder the diffusion of Cu up to 600 ℃; the Cu film by magnetron
sputtering process in vacuum failed at 700 ℃.

並列關鍵字

electroplating Cu ； ITO ； diffusion barrier

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