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Silicon dioxide growth curves produced by a rapid thermal processor were analyzed. No break point was observed in the growth curves. Of the kinematical models being compared, the linear-parabolic equation gave the best fit. However, the coefficients of the equation are thickness dependent as in the case of diffusion furnace oxide growth data. The correlation in the growth curves indicated similar oxide growth kinematics for the two types of oxidation equipment. Under certain oxidation conditions, the coefficient of the linear term may have a negative value and appears to be determined by the oxidation temperature and oxygen flow rate.

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Silicon dioxide growth curves were analyzed under a variety of oxidation conditions. The results indicated that the growth curve is not the linear-parabolic equation as predicted by the Deal-Grove model. Instead, a generalized form of linear-parabolic equation in which the coefficients are allowed to accommodate the change in the sign and thickness dependency may be desirable to describe the silicon oxidation process. It is also shown that the thickness dependency of the rate constant with appropriate approximations can be expressed explicitly in a functional form.

Magnetic properties of ultrathin Co∕Ge(111) films with oxygen surfactant have been investigated using surface magneto-optic Kerr effect technique. As the oxygen exposure increases, their magnetic properties could be significantly modified. As the thickness of Co films increases to above 6 ML (monolayer), pure cobalt islands start to accumulate on the surface and the amount of oxygen on the surface layers increases with increasing oxygen exposure time. Series experiments of different sequences of oxygen exposure and Co deposition have been performed. From the results of slight chemical shift and depth profiling measurements, one can conclude that oxygen plays a role as a surfactant. The adsorbed oxygen influences the electronic density of states of Co and leads to the changes of the magnetic properties. The appearance of the O∕Co∕Ge interface could modify the stress anisotropy, and as a result the coercivity of 30 ML Co∕Ge(111) increases from 730to810Oe with 500L of oxygen exposure.