We investigate the &bgr;‐SiC(100)3×2 surface oxidation by core level and valence band photoemission spectroscopies using synchrotron radiation. Low molecular O2exposures on the (3×2) surface reconstruction leads to direct SiO2/&bgr;‐SiC(100)3×2 interface formation already at room temperature (RT). To our best knowledge, this is the first example of RT oxidation leading directly to dominant silicon dioxide growth by O2chemisorption only. The amount of SiO2is enhanced when the surface temperature is raised by few hundred degrees only (<500 °C) during O2exposures leading to ‘‘bulk oxide’’ formation already at small thicknesses. These findings are also relevant in low‐temperature semiconductor oxide processing. ©1996 American Institute of Physics.