Fc. Stedile et al., IBA STUDY OF THE GROWTH MECHANISMS OF VERY THIN SILICON-OXIDE FILMS -THE EFFECT OF WAFER CLEANING, Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms, 85(1-4), 1994, pp. 248-254
The growth mechanisms of very thin silicon oxide films formed during r
apid thermal oxidation were studied using ion beam analysis and O-18 i
sotopic tracing methods. In this paper we report on the effects of dif
ferent cleaning procedures of silicon wafers prior to oxidation in dry
oxygen (O-16(2) followed by O-18(2)) on the growth mechanisms and kin
etics. Typical oxide thicknesses ranging from 0.2 to 10 nm were studie
d. The O-18 and O-16 isotopic profiles were determined by ion beam ana
lysis methods, namely: the O-18(p, alpha)N-15 narrow resonance at 151
keV, and the O-18(p, alpha)N-15 and the O-16(d, p)O-17 reactions assoc
iated with step-by-step chemical dissolution. The profiles could be re
lated to current theories on the initial stages of thermal growth of s
ilicon oxide layers allowing us to draw some conclusions regarding the
role of surface cleaning of the silicon wafers on the formation of si
licon fragments in the volume of the very thin oxide layer. The influe
nce of rapid thermal processing parameters like temperature, time and
oxygen partial pressure on the growth mechanisms were also studied and
discussed here.