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A characterization technique was developed for measuring the complete tensor nature of stress fields in semiconductors. By combining incident light tilted away from the normal axis with polarization of the incident and scattered beams, any Raman-active optical phonon mode can be selectively studied. Once the frequencies and intensities of these phonons are known, the complete stress tensor can be determined. Using this concept, a general, systematic theory and methodology for implementing polarized off-axis Raman spectroscopy was developed that took into account realistic effects which would be encountered in an actual experiment. This methodology was applied to mechanically deformed silicon wafers. By applying loads in different configurations across the wafer, various types of stress were created including tension, compression, and shear. The polarized off-axis Raman technique was validated by comparing its results to both analytic calculations based upon the theory of elasticity and to direct measurements of the wafer curvature using a laser deflection method.

Sputtered Ba1−xSrxTiO3 (BST) and SrTiO3 (STO) films and capacitors made with these dielectrics have been characterized with respect to physical and electrical properties. Specific capacitance values included a high of 96 fF/μm2 for BST films deposited of 600 °C and a high of 26 fF/μm2 for STO films deposited at 400 °C. Leakage current densities at 3.3 V for the most part varied from mid 10−8 to mid 10−6 A/cm2. All of the dielectrics are polycrystalline, although the lowest temperature STO films have a nearly amorphous layer which impacts their capacitance. Grain size increases with deposition temperature, which correlates to higher dielectric constants. The lattice parameter of the BST films is larger than that of bulk samples. Capacitance, leakage, breakdown, and lifetime results are reported.

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Physical and electrical characterization techniques have been applied to the problem of developing a lower temperature process for spin-on Ba 0.7 Sr 0.3 TiO 3 thin films and capacitors compatible with on-chip aluminum metallization. The films were prepared by spin-coating from carboxylate precursors and were processed at temperatures between 650 ± C and 450 ± C. Capacitors annealed at higher temperatures have a dielectric constant (k) of 382, a C͞A of 20 fF͞mm 2 , and a leakage current density of 2 3 10 27 A͞cm 2 at 3.3 V. Those processed at 450 ± C show occasionally promising but inconsistent results, correlated using TEM images with locally variable crystallization into the perovskite phase. The kinetics of the spin-on solution chemical decomposition and crystallization has been investigated through the use of x-ray diffraction (XRD), thermogravimetric analysis (TGA), and Raman spectroscopy.