低溫化複晶矽氧化層之製程及其在穿隧氧化層之影響

Abstract

在本論文中，我們發展出一套低溫化的複晶矽氧化層之製程並研究其在穿 隧氧化層之影響。這套製程結合了同時磷摻雜複晶矽(In-Situ Phosphorus Doped Polysilicon)與低壓氣相沉積系統(LPCVD)以四乙基環 氧矽化物(TEOS)沉積之複晶矽氧化層(TEOS Deposited Polyoxide)。 經 由這套製程所得到的複晶矽氧化層相較於傳統之複晶矽氧化層具有較優越 的電特性，譬如，較低的導電性、較高的崩潰電場、與較高的崩潰電荷密 度(Charge to Breakdown)。除此之外，藉著這套製程，在製造複晶矽氧 化層時，後複晶矽閘極之製程所引發之特性衰退(Post-Poly-Si Gate- Process-Induced degradation)，闢如，崩潰電荷密度(Charge to Breakdown)與應力引發漏電流(Stress-Induced Leakage Current)皆明顯 獲得改善。 The low-temperature (≦700℃) fabrication of interpolysilicon oxide and its impact ontunnel oxide is studied. This process combines the in-situ phosphorus dopedpolysilicon and TEOS deposited oxide. The obtained interpolysilicon oxide has superior electrical characteristics such as lower conductivity, higherbreakdown electric field, and higher Qbd than those of conventional interpolysilicon oxide. Moreover, during fabricating interpolysilicon oxide , the post-polsilicon gate- process-induced degradation such as Qbd and stress-induced leakage current degradation of tunnel oxide can be evidently lessenedby this method.