全金屬矽化物多晶矽閘極之研究

下一世代的金屬半場效電晶體需要導入金屬閘極(metal gate)，以作為未來的效能提昇之用，而實現金屬閘極的一個關鍵挑戰，是必須具有合適金屬功函數。在本文中，MOS結構採用全金屬矽化物閘極取代傳統的多晶矽閘極，和金屬閘極相同，在材料的選擇上，除了附著力、抗氧化、防腐蝕、熱穩定、與易沉積蝕刻特性等製程上的考量外，還須瞭解其功函數(work function)值。另外，本文研究MOS電容全金屬矽化鈦閘極之功函數調變，比較在多晶矽金屬矽化前摻雜不同雜質鉮、磷，結果顯示，無摻雜、摻雜鉮(1×1015cm-2)和爐管摻雜磷之矽化鈦閘極功函數分別估計為4.25eV、4.2eV和4.55eV。具功函數可調性之全金屬矽化鈦閘極為深具潛力之CMOS技術。本文研究MOS電容之全矽化鎳矽化物金屬閘極之功函數調變,比較全矽化RTP製程之不同溫度450℃，650℃後，結果顯示，Ni2Si和Ni3Si閘極已形成且其功函數分別估計為4.22eV和4.52eV。

關鍵字

全金屬矽化物；功函數；矽化鈦；矽化鎳

並列摘要

The Metal-Oxide-semiconductor Field-Effect Transistor (MOSFET) needs to use the metal gate to improve the efficiency in next generation. However, to choose a proper work function of metal gate is a crucial challenge. In this dissertation , we use fully silicided polysilicon gate instead of conventional polysilicon gate in MOS structure. To be a proper metal gate,it needs to not only consider the adhesion of interface, anti-oxidation, corrosive resistant, thermal stability and etching during MOS device processes but also its work function. This paper investigates the work function tuning on fully silicided (FUSI) Ti silicide metal gates for MOS capacitor. By doping different impurities As, P into poly-Si before silicidation, it is shown that the WFs of TiSi2 gate electrodes with undoping, As doping(1×1015cm-2)and P in-situ doping were estimated to be 4.25 eV, 4.2 eV and 4.55 eV, respectively. FUSI Ti silicide is a potential candidate for CMOS technology with tunable work functions . This paper investigates the work function tuning on fully silicided (FUSI) Ni silicide metal gates for MOS capacitor By comparing FUSI RTP process on different silicidation temperatures 450℃,650℃, it is shown that the of Ni2Si and Ni3Si gate electrodes were formed and their WFs were estimated to be 4.22 eV and 4.52 eV, respectively.

並列關鍵字

FUSI ； Work Function ； Titanium Silicide ； Nickel Silicide

參考文獻

[1] J.P.Gambinoa, E.G. Colgan, “Invited Review Silicide and ohmic contacts”,p.99-146(1998)

Google Scholar

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