為了滿足ITRS元件持續縮小化的要求，一般廣泛的認為高介電係數材料將取代原本的二氧化矽成為金氧半元件閘極介電層來改善漏電流的問題，然而在材料替換的過程中，許多問題產生，如電荷捕獲(charge trapping)，臨界電壓(threshold voltage)飄移，載子遷移率下降(mobility degradation)等，因此應用在高介電係數閘極介電層電晶體的界面陷阱(interface traps)及氧化層陷阱(oxide traps)可靠度分析因應而生。
　　論文中第一部份介紹電荷汲引(charge pumping)技術量測方法。利用電荷汲引量測不同high-κ厚度介電層電晶體的界面陷阱密度與邊緣陷阱密度。描繪出陷阱空間中的分佈以及在矽能隙中能量的分佈情形。
　　接著透過分析CVS而產生的臨界電壓飄移隨時間的不同，可發現有缺陷捕捉(trapping)和電應力產生缺陷(stress-induced defects)的階段性區別。其中閘極氧化層缺陷(oxide trap)在臨界電壓的飄移佔了主要成分，所以因電應力而產生的陷阱也較嚴重。建議主要限制元件使用年限(life time)的原因也以改善閘極氧化層缺陷為優先。
　　在論文的最後一部分，應用空乏區和變頻的方法結合在電荷汲引技術上，可以用來量測在電晶體接面(junction)邊上三維陷阱密度的分布情形。利用上述的三維量測方法，對電晶體施加CVS和CHCS之可靠度使用條件進行分析。可發現隨所施加的電應力(stress)不同，在空間性上產生的陷阱密度分部情況也有很大的不同。期望在空間性上的瞭解為改善元件特性的製程方法提供方向。

For satisfy ITRS rule to keep device scale down. General method use high-kapa material which replaced silicon dioxide MOSFET to overcome gate leakage problem. But there are more issues in the process. Such as charge trapping, threshold voltage shift, mobility degradation, et al. Becasue of the problem mentioned, technique to detect interface traps and oxide traps be developed.
In the first part of thesis, introduce charge pumping technique. Use CP method to measure interface trap and border trap in different gate dielectric thickness MOSFET. To understand the trap energy distribution in silicon bandgap.
In the second part of thesis, experiment study the Constant-Voltage-Stress which shift threshold voltage in different time. The staged degredation can separate as trapping and stress-induced defects. After, experimental study discover oxide trap dominate the threshold voltage shift in trapping stage. And stress induced trap generation come from oxide trap are more serious. So, improve oxide trap in MOSFET would be first priority to satisfied life time restraint.
In the last part of thesis, experiment combine depletion region method and frequency method in Charge Pumping technique to measure device's junction side spatial distribution. And use this 3D distribution to detect trap generation after CHCS and PBTI reliability test. Experimental study discover the stress could be different spatial damaged in device. Wish using this knowledge help to improve device.

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