NO 氮化超薄氧化層可靠性之研究及其在極大型積體電路之應用

Abstract

隨著次微米元件尺寸之縮小，超薄閘極氧化層的可靠性分析益形重要。而 氮氧化層提供高強度的界面鍵結，因而擁有較低的電荷捕捉、界面缺陷密 度、以及高崩潰電荷等特性。本論文將針對以快速加熱系統所加熱成長之 氧化層，用 NO 氣體氮化處理，探討其特性；並對結果加以討論。用 NO 氣體來氮化閘極介電質，不僅易於控制厚度﹙因其成長速度非常慢緣故﹚ ，且沒有氫原子伴隨的缺點。界面累積高濃度的氮，亦加強氧化層電性的 可靠度，但是實驗結果顯示，過量的氮化將對元件造成若干壞；本文中亦 對最佳氮化條件，做一番探討。 As device dimensions are scaled down into the deep-submicron regime, ultrathin gate dielectric films with excellent physical and electrical properties are required. The nitrided gate dielectrics can fulfill the requirements of low charge trapping rate, low interface state generation, high charge to breakdown (QBD) and high resistance to process induced damage. In this study, we present the fabrication process of RT SiO2+NO annealed gate dielectrics, followed by a discussion of the experimental results. The in-situ NO-annealed SiO2 in a RTP system is extremely useful for the ULSI technology due to its process simplicity, H-free nature, high self-limiting growth and low thermal budget. Higher nitrogen pile-Up in SiO2/Si interface enhanced the interface endurance, reduced charge trapping rate, and increased charge to breakdown. Effective barrier properties to boron diffusion and hardness of radiation induced degradation are obtained at the same time. In addition, optimization of NO- based oxynitride has define in this work.