Stress Measurements of Thermally Grown Thin Oxides on (100) Si Substrates

The results of film stress measurements on thermally oxidized silicon substrates are presented and discussed. The oxides were grown to thicknesses ranging between 9.0 and 37.0 nm at 800°–1000°C in dry with 4.5% at atmospheric pressure on double‐side polished, 100 μm, 0.5 and 0.1 Ω‐cm, p‐type (100) Si wafers. The oxide film stress was determined through curvature measurements using a single beam laser reflection technique, which is described. The total compressive film stress, as measured at room temperature, was on the order of . The intrinsic film stress, i.e. , the total stress less the thermal coefficient of expansion stress, was found not to depend on the thickness of the oxide grown at a given oxidation temperature in the thickness range studied. The intrinsic stress decreased linearly with increasing oxidation temperature for oxides of similar thickness. It was found that the total oxide film stress was the same for samples grown on 0.5 Ω‐cm and 0.1 Ω‐cm substrates. Comparisons of curvature measurements of the bare Si wafers before processing and after removal of the grown oxide occasionally showed the occurrence of plastic deformation of the substrates during the oxidation process. The effects of this plastic deformation are considered.