SiO 2 film thickness metrology by x-ray photoelectron spectroscopy

Silicon dioxide films grown by industrial thermal furnace, rapid thermal, and low-pressure thermal methods were measured by x-ray photoelectron spectroscopy, transmission electron microscopy (TEM), spectroscopic ellipsometry, and capacitance–voltage analysis. Based on TEM measurements, the photoelectron effective attenuation lengths in the SiO2 and Si are found to be 2.96±0.19 and 2.11±0.13 nm, respectively. The oxide physical thicknesses (range from 1.5 to 12.5 nm) as measured by all above techniques are in good agreement. The electrical thickness is noted to be slightly thicker than the physical thickness.