鍺具有高載子遷移率，但GeO2/Ge介面較差，閘極堆疊中介面品質和微縮等效氧化層厚度的議題是十分重要的，合適的閘極堆疊是實現高性能鍺金氧半元件的關鍵，透過各種電漿或高壓水處理可以改善氧化物及介面品質，本論文在ZrO2/Al2O3/GeOx中研究了三種閘極堆疊的處理技術，以改善pMOSFET的電特性。
首先，研究了原位通入O2退火、O2電漿以及H2O電漿的閘極氧化物沉積後處理之鍺金氧半元件，通入O2退火的元件實現了良好的電特性，顯示出最低的次臨界擺幅和最高的導通電流。
其次，研究了CF4電漿處理的氧化物和O2、N2或O2混合N2電漿處理在鍺金氧半元件中的效應，介面確實能夠被氟電漿鈍化，而且閘極漏電流能夠被O2混合N2電漿處理進一步抑制，在FN Stress之後，氟電漿處理的樣品具有較低的gmmax和S.S.退化。
第三，應用超臨界流體處理來鈍化ALD形成的閘極氧化物，通過SCCO2將H2O分子帶入氧化物薄膜中，並且可以通過添加乙醇來增強反應，SCCO2 + H2O +乙醇的處理可以減少閘極介電層中的缺陷，結果顯示，超臨界流體處理樣品具有較低的次臨界擺幅和較好的可靠度。
最後，研究了鋁摻雜的ZrAlOx在ZrAlOx/Al2O3/GeOx Ge pMOSFET中的影響，透過交錯堆疊將一些氧空缺摻入閘極氧化物中，搭配金屬後退火可以增強結晶性，同時，ZrAlOx具有較大的能隙可以抑制閘極漏電流，而研究發現，Zr0.18Al0.18Ox/Al2O3/GeOx樣品擁有最小的次臨界擺幅同時具有低閘極漏電流，在可靠度的部分，採用ZrAlOx的樣品具有較低的gmmax和S.S.退化並且因應力所引起的漏電流效應較小。

Germanium has high carrier mobility, but GeO2/Ge interfaces are poor. The issue of interface quality and scaling down of the equivalent oxide thickness in the gate stack are important. A suitable gate stack is a key for achieving high-performance Ge MOS device. The oxide and interface quality can be improved by various plasma or high pressure H2O treatment. In this thesis, three kinds of gate stack treatments on ZrO2/Al2O3/GeOx are studied to improve electrical characteristics of Ge pMOSFET.
First, in-situ annealing in O2 flow, O2 plasma and H2O plasma treatments after the gate oxide deposition Ge MOS device are investigated. Good electrical characteristics are achieved in O2 flow sample, showing the lowest S.S. and highest on current.
Second, effects of CF4 plasma treated oxide and O2, N2 or O2 mix N2 plasma treatment in Ge MOS are investigated. The interface is indeed passivated by fluorine plasma treatment. And, the gate leakage current is suppressed by O2 mix N2 plasma treatment. After FN Stress, fluorine plasma treated sample has lower gmmax and S.S. degradation.
Third, supercritical fluid treatment is applied to passivate the ALD formed gate oxide. The H2O molecules are carried into the oxide film by SCCO2, and the reaction can be enhanced by adding ethanol. The defects in gate dielectric can be reduced by SCCO2+H2O+ethanol treatment. The results show that supercritical fluid treatment sample has lower subthreshold swing and better reliability.
Finally, the effects of Al-doped ZrAlOx in ZrAlOx/Al2O3/GeOx on Ge pMOSFET are studied. Some oxygen vacancy is incorporated into gate oxide by co-deposition. The crystallization of gate dielectric can be enhanced with post-metal annealing. At the same time, ZrAlOx has a large band gap to suppress gate leakage current. It’s found that the samples with Zr0.18Al0.18Ox/Al2O3/GeOx show the lowest subthreshold swing with low gate leakage current. Regarding the reliability characteristics, ZrAlOx sample has lower gmmax and S.S. degradation and much less stress induce leakage current effect.

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