超薄氮化矽氧化層金氧半場效電晶體特性之研究

Abstract

在本論文中，我們成功製備出超薄氮化矽閘極氧化層之電晶體，並佐以氟離子之矽基板離子佈植，綜合討論電晶體特性的改變與改善。 我們也採用一氧化二氮(N2O)氣體對超薄氮化矽閘極氧化層進行900oC,30sec,快速熱退火處理，嘗試製造出較高的介面層氧原子濃度以改進載子遷移率等電晶體特性。 這兩個部分中，我們都證明了氟離子步植對於電晶體電性有相當顯著的電性改善。 最後一個部分我們嘗試將500Å厚度之選擇性磊晶矽鍺通道整合入超薄氮化矽閘極氧化層金氧半場效電晶體的製程中。 P型以及N型電晶體，都表現出很良好的直流特性以及相當低的漏電流，足以證明此單層選擇性磊晶矽鍺通道製程未來應用於高速P型金氧半場效電晶體之可行性。

In the thesis, we successfully fabricated mosfets with ultra thin silicon nitride gate dielectric, combined with fluorine silicon substrate ion implantation in order to comprehensively discuss the changes and improvements of device characteristics. To get a oxygen-riched interface, we also applied 900oC, 30sec, N2O annealing on the ultra thin SiN gate dielectric mosfets to enhance the carrier mobility. In these two parts, obvious electrical characteristic improvements are proved through the fluorine ion implantation. In the last section, we tried to incorporate 500Å selective epitaxy silicon germanium channels into the process of ultra thin SiN gate dielectric mosfets. Both pMOSFET and nMOSFET show fair DC characteristics and fairly low leakage current, which demonstrates the viability of single-layered selective epitaxy SiGe channel on high speed pMOSFET in the future.