Stress measurement of SiO/sub 2/-polycrystalline silicon structures for micromechanical devices by means of infrared spectroscopy technique

FTIR (Fourier-transform infrared) spectroscopy was used to analyze polysilicon-oxide-silicon structures. The results obtained show that this technique is adequate for measuring induced stress produced by technological processes in micromechanics. Variations were observed in the absorption peak of the oxide among different samples depending on the technological characteristics. X-ray diffraction was also used to analyze the state of stress in the polysilicon layer. The two kinds of measurements are clearly correlated. >