Formation of ultrathin silicon oxides—modeling and technological constraints

Abstract

The “ITRS Roadmap” suggests the necessity of constant reduction of dielectric thickness for a number of important applications in ICs technology. The technology of ultrathin layers is, however, very difficult. So is modeling. During the last two decades a number of theoretical models of silicon oxidation, based on different approaches and assumptions, were constructed in order to surpass limitations of the commonly used Deal–Grove model. They will be critically reviewed and discussed in this paper. More attention will be paid to Beck–Majkusiak model, which gives precise predictions even for ultrathin oxide thickness regime, for both: classical oxidation in furnace, and for processing in RTO reactor, and is consistent with description of plasma oxidation process. Some problems of modeling result from technological constraints or measurement methods available. These issues are also briefly addressed in this paper.