本實驗利用高效能濺鍍系統於矽基板上成長二氧化鉿-二氧化鈦相關高效能組合式高介電氧化物樣品組，並製作成金屬氧化物半導體結構，探討其結構-成分-性質之關係。
從單一成分二氧化鉿與二氧化鈦試片，我們可以發現其均具有良好之厚度梯度變化，此顯示了我們可以製作高可靠度之二氧化鉿-二氧化鈦組合式高介電氧化層薄膜樣品組。利用穿透式電子顯微鏡得知其非晶相氧化層厚度約十奈米，且鈦之成分比例由純二氧化鉿區域線性地增加至純二氧化鈦區域。其介面層厚度約兩奈米，且成分主要為非晶相之二氧化矽並伴隨極少量之金屬矽化物。
經計算後可知其介電常數隨著二氧化鈦成份之增加可由13提升至約50，但其相對應之漏電流密度也會持續地由10-8上升至10-4 (面積/公分2 )。我們得知其最佳成分為0.69二氧化鉿-0.31二氧化鈦，其介電常數約為42；等效氧化層厚度約0.9奈米 ，並擁有可信賴之漏電流密度約10-6(面積/公分2 )與電容-電壓曲線。
藉由參雜氮進入此二氧化鉿-二氧化鈦相關高效能組合式高介電氧化物樣品組，可以大幅提升其二氧化鈦之成分使試片之組成成份為0.32二氧化鉿-0.68二氧化鈦，並仍然保有良好之電容-電壓曲線。 雖然參雜氮後電容值會稍微降低但卻可改善其漏電流密度約兩個級數。此意味著此氮參雜之0.32二氧化鉿-0.68二氧化鈦試片組為一極具有潛力之成分比應用於先進金屬閘極。

In this thesis, HfO2-TiO2 related composition spreads are deposited on Si substrates as the dielectric layers for MOS structure devices using the state-of-the-art combinatorial sputtering system. The structures-properties -compositions relationship was studied.

We have exhibited our capability for making good quality thickness gradients (wedges) of both single composition layers and HfO2-TiO2 composition spreads. The thicknesses of amorphous oxide layers are determined to be around 10 nm across the composition spread sample using high resolution transmission electron microscopy (HRTEM). Ti ratios are systemically increasing from HfO2-rich to TiO2-rich, extracted from the electron probe energy dispersion spectroscopy (EDX) analysis. The interfacial layers between the oxides and the Si substrate are  2nm, consisting of HfSiO-rich (close to HfO2-rich) to TiSiO-rich (close to TiO2-rich). The extracted dielectric constant values across the HfO2-TiO2 composition spread are from 13 to 50, with increasing Ti ratio. The corresponding leakage current densities (JL) are continuously increasing from  10-8 to  10-4 (A/cm2 ). We found the compositions near 0.31TiO2 possesses the dielectric constant of  42, while maintains reasonably low leakage current density (10-6 A/cm2 ). The calculated EOT of this composition was  0.9 nm.

For the N2-doped HfO2-TiO2 composition spread samples, we found that good C-V characteristics could be obtained with much higher TiO2 contents (up to 0.69TiO2), which is usually too leaky to show a good accumulation behavior in a no N2 incorporation samples. Their corresponding JL was also found that orders lower than that of no N2 doped samples. Although the map of dielectric constants yet to be determined, it potentially indicates a better dielectric properties could be obtained from the N2 doped HfO2-TiO2 composition spreads.

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