2-DIMENSIONAL SIMULATION OF LOCAL OXIDATION OF SILICON - CALIBRATED VISCOELASTIC FLOW-ANALYSIS

Local Oxidation of Silicon (LOGOS) remains the common isolation techno logy for mass-production of integrated circuits, The work reported in this paper contributes to the improvement of the numerical modeling of the LOGOS process, A physical two-dimensional (2-D) modeling of the t hermal oxidation of silicon has been developed based on the explicit t reatment of the reaction expansion. The originality of this modeling i s to propose a general solution taking into account of the silicon def ormation, incorporating the viscoelastic behavior of oxide and nitride and, particularly, giving a complete calibration of the stress-depend ent parameters. The prediction capabilities are demonstrated by the ca lculations of oxide shapes and oxidation-induced stresses in silicon s ubstrate for very advanced isolation techniques.