鈦、鎢擴散障礙層在鋁/鉑矽化物/矽結構上之研究

Abstract

本論文旨在探討鈦- 鎢合金層作為鋁與矽化鉑間之擴散障礙層，於熱處理 時之穩定性，而鋁/ 鈦- 鎢/ 矽化鉑接觸之蕭特基二極體( n 型矽基體) 以及p+ n或n+ p接面二極體將作為本文研究之用。我們可以利用二次離子 質譜儀(SIMS)、掃描式電子顯微鏡 (SEM)、片電阻以及電性之測量，來探 討其介面間之反應，約1500埃厚之鈦- 鎢薄膜，在氮氣爐管中退火時，可 以阻止鋁與矽化鉑層間之相互反應，直到 400℃ 30分鐘的退火。對於 鋁/ 鈦- 鎢/ 矽化鉑接觸之p+ n或n+ p接面二極體，即使經過 550℃ 30 分鐘的退火，仍能展現出一個非常好的電性。此外，當在鈦- 鎢合金層濺 鍍時混入氮氣能改善鈦- 鎢擴散障礙層的特性。 This layer of Ti-W alloy as an diffusion barrier between Al and PtSi during thermal treatment has been investigated. The Al/Ti- W/PtSi contacted Schottky diodes (n-Si) and junction diodes (n+ p and p+n) were employed for this study. The inter- facial reaction was investigated by secondary-ion mass spect- roscopy, sheet resistance measurement, scanning electron mic- roscopy, and electrical measurements. The Ti-W film with a thickness of 1500o prevents Al-PtSi interaction up to 400℃ for 30 min annealing in N2. For the Al/Ti-W/PtSi contacted p+n or n+p junction diodes, fairly good electrical character- istics can preserved even after 550℃ annealing for 30 min. In addition, the Ti-W barrier properties can be improved by inco- rporation of nitrogen during the sputter deposition of the Ti- W layer.