FORMATION OF HIGH-QUALITY ULTRATHIN OXIDE NITRIDE (ON) STACKED CAPACITORS BY IN-SITU MULTIPLE RAPID THERMAL-PROCESSING

Abstract

High quality, ultrathin (<30 Angstrom) SiO2/Si3N4 (ON) stacked film capacitors have been fabricated by ill situ rapid-thermal multiprocessing. Si3N4 film was deposited on the RTN-treated poly-Si by rapid-thermal chemical vapor deposition (RTCVD) using SiH4 and NH3, followed by in situ low pressure rapid-thermal reoxidation in N2O (LRTNO) or in O-2 (LRTO) ambient, While the use of low pressure reoxidation suppresses severe oxidation of ultrathin Si3N4 film, the use of N2O-reoxidation significantly improves the quality of ON stacked film, resulting in ultrathin ON stacked film capacitors with excellent electrical properties and reliability,