於氟離子佈植之矽基板上製備之超薄閘極氧化層

Abstract

隨著深次微米元件尺寸的縮小，超薄閘極介電層的可靠性日益重要。在本論文中,我們利用離子佈植將氟元素摻雜於矽基板內，藉由氧化過程成長40-75埃厚的氧化層，並使氟元素擴散到氧化層內，以形成Si-F鍵結。利用各種的電性應力方式，來分析此氧化層的可靠性。 由實驗顯示，適量的摻雜有助於氧化層特性的改善，但過量摻雜氟元素會造成氧化層劣化的情形。此是因為Si-F的鍵結能量較大，經由高電流、高電場施壓時，不易打斷鍵結。另外，我們也藉著鈷60輻射照射，探討前後的特性之變化。超薄氧化層中的假性崩潰特性亦在此討論，並且因氟元素摻雜的效果，使超薄氧化層擁有更佳的可靠度。

As the device dimensions are scaled down into the deep-submicron regime, the ultra-thin gate dielectric film with excellent reliability is required. In this thesis, we implant F into the silicon substrate by ion implantation, and then grow 40-75A silicon dioxide, analyze the reliability of this ultra-thin silicon dioxide, by using several kinds of electrical stressing. From the study, it was found that with the appropriate dosage of fluorine the characteristics of silicon dioxide films were improved. However, it was shown that the excessive dosage of F would degrade the quality of silicon dioxide films. Further more, the characteristics of silicon dioxide films before and after Co60 radiation is studied, and the quasi-breakdown in ultra-thin oxide is also discussed here. Overall, it is shown that with the F-incorporation, the ultra-thin oxide can have better reliability.