中文摘要
　　本研究主要探討鉭基氮化物擴散阻礙層在不同溫度下對銅金屬和
砷化鎵間擴散阻礙行為與失效的機制。實驗以反應式磁控法在砷化鎵
基板上以不同的Ar/N2分壓比例濺鍍鉭靶或氮化鉭靶成長鉭基氮化物
阻礙層，銅金屬以相同方式濺鍍其上，隨後進行真空封管並在不同回
火氣氛下進行高溫退火。藉由X光繞射的結構觀察以及X光光電子能譜
能量的定量分析，探討鉭基氮化物阻礙層的阻礙失效行為。
實驗結果顯示鉭基氮化物可以在真空環境575℃下一小時內阻礙銅金
屬和砷化鎵間之擴散效應，而在鎵或砷的氣氛下進行退火，並不能有
效提升耐熱溫度和壓抑銅金屬和砷化鎵間之擴散問題。其失效機制可
能源自於當外界溫度高於580℃時,砷化鎵基底開始自身解離,高氣壓
砷原子外溢,加速降低鉭基氮化物阻礙銅與砷化鎵相互間擴散的能力。

Abstract
The behaviors of the TaNx barrier layer that placed
between the Cu metal and GaAs have been studied
by using X-ray diffraction, X-ray photoelectron
spectroscopy and scanning electron microscopy.
The TaNx and Cu films were deposited on GaAs
sequentially with RF magnetron sputter.
With a 250 nm thick TaNx barrier layer, the Cu
metal can be impeded from reacting with GaAs
substrate at 575℃annealed for one hour.
Within an As or Ga overpressure environment condition,
the failure temperature still occurred below 600℃.
The failure of TaNx diffusion barrier layer for
preventing the reaction of the Cu and GaAs was originated
for the dissociation of the GaAs itself at 580℃.
The outgoing As atoms increased the deterioration speed
of the TaNx film and reduced its blocking ability.

第一章 導論 1
1.1 砷化鎵MOS場效電晶體的發展 1
1.2 金屬鋁的瓶頸與銅金屬時代的來臨 2
1.2.1 金屬鋁的瓶頸 2
1.2.2 銅金屬的發展 3
1.3 擴散阻礙層 3
1.4 研究緣起 5
第二章 理論 6
2.1 砷化鎵基板材料特性 6
2.2 鉭金屬和鉭基氮化物的結構與特性 7
2.2.1 鉭金屬和鉭基氮化物的結構與性質 7
2.2.2 鉭金屬和鉭基氮化物的電阻率 7
2.3 文獻回顧 8
2.3.1鉭基氮化物在矽基板和銅金屬間之
擴散阻礙行為機制 8
2.3.2 砷化鎵基板上擴散阻礙層的研究 8
2.4 反應性射頻磁控濺鍍原理 9
2.4.1 濺鍍原理 9
2.4.2 射頻磁控原理 10
2.5 X光光電子電子能譜（XPS）原理 10
第三章 實驗步驟與分析方法 13
3.1 實驗設備介紹 13
3.2 實驗流程 13
3.2.1 基板清潔 14
3.2.2 鉭基氮化物薄膜和銅膜的鍍製 15
3.2.3 封管 16
3.2.4 退火（annealing） 17
3.3 薄膜的分析 17
3.3.1 X光繞射儀分析 17
3.3.2 X光光電子電子能譜分析(XPS) 18
3.3.3 掃描式電子顯微鏡分析 18
3.3.4 電子微探針分析儀(EPMA) 18
3.3.5 鉭基氮化物電性分析 19
3.3.6 表面測量儀（Surface profile） 20
第四章 實驗結果與討論 21
4.1 X光光電子能譜儀定量分析結果 21
4.1.1 鉭基氮化物定量分析結果 21
4.1.2 鉭基氮化物束縛能偏移的探討 21
4.2 鉭基氮化物的X光繞射儀分析 22
4.3 鉭基氮化物擴散阻礙層在真空環境下
熱處理後之分析 23
4.3.1 有無鉭基氮化物擴散阻礙層
的XRD分析比較 23
4.3.2 鉭基氮化物擴散阻礙層在砷化鎵
基板上耐火程度之探之分析 23
4.3.3 鉭基氮化物擴散阻礙層在玻璃
基板上耐火程度之探討分析 24
4.4 不同氣氛下退火之XRD分析 25
4.4.1 鎵氣氛環境退火之XRD分析 25
4.4.2 砷氣氛環境退火之XRD分析 27
4.5 掃瞄式電子顯微鏡下退火後晶粒
大小的探討 27
4.6 電子微探針分析儀定量分析結果 29
4.7 電性量測 29
第五章 結論 30
參考文獻 31
圖目錄
圖2-1 f.c.c晶體結構 36
圖2-2 砷化鎵晶體結構（閃鋅礦結構，zincblende） 36
圖2-3 砷化鎵之電子漂移速度圖 37
圖2-4 砷化鎵之能隙圖 37
圖3-1 濺鍍實驗系統示意圖 38
圖3-2 實驗流程架構示意圖 39
圖3-3 真空封管系統架構圖 40
圖3-4 真空封管過程示意圖 40
圖3-5 置放雜質源的封管示意圖 41
圖3-6 出爐時冷卻方法意圖 41
圖4-1 鉭基氮化物（Ta、Ta2N、TaN ）外層電子4f7/2和4f5/2軌域的束縛能 42
圖4-2 鉭基氮化物外層電子4f7/2和4f5/2軌域的束縛能（a）150W Si（b）150W Glass（c）200W Si（d）200W Glass 43
圖4-3 表4-2中M、N、O、P組的X光繞射圖譜（a） M (200W, 9.5/0.5) （b）N (150W, 9.5/0.5) （c）O (150W, 13/0.5) （d）P (150W, 18/0.5) 44
圖4-4 表4-2中Ⅰ、Ⅱ、Ⅲ、Ⅳ組的X光繞射圖譜（a）Ⅰ(50W, 5/0)（b）Ⅱ(50W, 5/0.5)（c）Ⅲ(100W, 7.5/0)（d）Ⅳ(100W, 7.5/1)45
圖4-5 表4-2中Ⅴ、Ⅵ、Ⅶ、Ⅷ組的X光繞射圖譜（a）Ⅴ(150W, 7.5/1) （b）Ⅵ(175W, 6.5/1) （c）Ⅶ(175W, 8.5/1) （d）Ⅷ(200W, 9.5/0.5) 46
圖4-6 真空氣氛、不退火情況下的X光繞射圖譜（a）無鉭基氮化物阻礙層（Cu/GaAs）（b）有鉭基氮化物阻礙層（Cu/TaNx/GaAs） 47
圖4-7 真空氣氛、不同熱處理一小時下，鉭基氮化物在砷化鎵基板和銅膜間〔Cu(324nm) / TaNx (141nm) / GaAs〕的X光繞射圖譜（a）未退火（b）500℃（c）600℃ 48
圖4-8鉭基氮化物在砷化鎵基板和銅膜間〔Cu(284nm)/TaNx (212nm)/GaAs〕退火一小時後的X光繞射圖譜（a）575℃（b）625℃ 49
圖4-9 鉭基氮化物在玻璃基板上退火一小時後的X光繞射圖譜（a）未退火（b）400℃（c）500℃（d）600℃ 50
圖4-10 鎵氣氛環境、不同基板〔Cu (284nm)/ TaNx (212nm)/ Sub.）、不同溫度下退火一小時後的X光繞射圖譜（a）600℃玻璃基板（b）600℃砷化鎵基板（c）650℃砷化鎵基板 51
圖4-11 砷氣氛環境、不同基板〔Cu (284nm)/ TaNx (212nm)/ Sub.〕、不同溫度下退火一小時後的X光繞射圖譜（a）575℃砷化鎵基板（a1）575℃玻璃基板（b）600℃砷化鎵基板（b1）600℃玻璃基板（c）650℃砷化鎵基板 52
圖4-12 真空氣氛下（a）不退火（b）575℃（c）650℃（d）700℃退火一小時後，鉭基氮化物在矽基板上（TaNx/Si）經酸蝕刻後表面之SEM圖 53
圖4-13 真空氣氛下（a）575℃（b）700℃退火一小時後，銅膜在鉭基氮化物上（Cu/TaNx/Si）經酸蝕刻後表面之SEM圖 55
表目錄
表2-1 砷化鎵在室溫時（300 K）之特性 56
表2-2 鉭金屬和鉭基氮化物之結構特性 57
表2-3 砷化鎵基板上擴散阻礙層之相關文獻整理 58
表3-1 銅、銅鎵、銅砷化合物之X光繞射資料 59
表3-2 鉭、鉭基氮化物、鉭鎵、鉭砷化合物之X光繞射資料 62
表4-1 XPS數據整理表格 65
表4-2 成長鉭基氮化物實驗之變動參數及數值 66
表4-3 不同氣氛、溫度退火實驗整理 67
表4-4 EPMA實驗結果 68

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