We explore the relationship between religiosity and public support for greater government services. We theorize that increases in religiosity and public opinion both reflect demands from citizens in the face of insecurity. We argue that religiosity is comprised of two factors: responses to insecurity; and long-held preferences for religion, or secularity. We show that previous studies that have observed increased religiosity leading to decreased support for government spending have not distinguished among religiosity as driven by secularity versus insecurity. To test our theory, we first estimate a series of simulations, and we then turn to the dynamics of aggregate religiosity and public opinion in the United States over the past fifty years, an environment where long-held preferences for religious goods have remained relatively stable. Consistent with our theory, religiosity and public opinion respond to insecurity; the series are positively correlated, move together through time, and react in similar ways to changes in GDP per capita. Our findings indicate that during times when there is greater insecurity, both religiosity and demand from government increase.

The assessment of the thermal stability across HfO2/Si and HfO2/SiO2 interfaces has been difficult due to lack of thermodynamic data. In this paper, we present the results of thermodynamic calculations intended to fill this gap. A thermodynamic model was developed by assuming that HfSiO4 is an ideal solution of HfO2 and SiO2 to a first order approximation. The theoretical results predict that the HfO2/Si interface is thermodynamically stable up to 1100°C, while the HfO2/SiO2 interface is thermodynamically unstable even at room temperature. Our experimental results from TEM and XPS analysis are consistent with these modeling predictions.

We present experimental results regarding the thermodynamic stability of the high-k dielectrics ZrO2 and HfO2 in contact with Si and SiO2. The HfO2/Si interface is found to be stable with respect to formation of silicides whereas the ZrO2/Si interface is not. The metal oxide/SiO2 interface is marginally unstable with respect to formation of silicates. Cross-sectional transmission electron micrographs expose formation of nodules, identified as silicides, across the polysilicon/ZrO2/Si interfaces but not for the interfaces with HfO2. For both ZrO2 and HfO2, the X-ray photoemission spectra illustrate formation of silicate-like compounds in the MO2/SiO2 interface.

The microstructure and integrity of thin silicon films on SiO2 after immersion in 10:1 buffered HF solution were investigated by AES, AFM and TEM measurements. Silicon films of 30 nm - 50 nm thicknesses were deposited on 15 nm of thermal oxide by LPCVD using SiH4 at 550 °C, 580 °C and 625 °C. These films were then treated with the HF for 15 seconds and characterized systematically. The data provided direct physical evidence for etching of gate oxide by the HF solution through defects (holes) in the 580 °C Si film.

The growth and surface morphology of thin LPCVD silicon films were investigated with an atomic force microscope (AFM). Silicon films of 30 nm thicknesses were deposited on SiO2 using SiH4 at four different temperatures between 550 °C and 625 °C. These AFM results permitted visualization of silicon surface granularity, roughness, and the transition with temperature from amorphous to crystalline structure between 550 °C and 580 °C. The surface of the amorphous film deposited at 550 °C is very smooth and the film is continuous physically, while the film formed at 580 °C appears crystalline, rough and porous. At 600 °C and 625 °C the films are fully crystalline. For these higher temperature films surface roughness and the average grain size decreased significantly compared to 580 °C film. Crystallinity and film continuity were further examined by x-ray diffraction (XRD) and cross-sectional TEM measurements.

The growth and surface morphology of thin LPCVD silicon films were investigated with an atomic force microscope (AFM). Silicon films of 30 nm thicknesses were deposited on SiO2 using SiH4 at four different temperatures between 550 °C and 625 °C. These AFM results permitted visualization of silicon surface granularity, roughness, and the transition with temperature from amorphous to crystalline structure between 550 °C and 580 °C. The surface of the amorphous film deposited at 550 °C is very smooth and the film is continuous physically, while the film formed at 580 °C appears crystalline, rough and porous. At 600 °C and 625 °C the films are fully crystalline. For these higher temperature films surface roughness and the average grain size decreased significantly compared to 580 °C film. Crystallinity and film continuity were further examined by x-ray diffraction (XRD) and cross-sectional TEM measurements.

Thin film properties of LPCVD TiN barriers deposited on Si(100), using TiCl4 and NH3 as reactants, were investigated as a function of deposition temperature between 400 °C and 700 °C. The TiN film chemistry and film composition were studied by AES and RBS techniques, while the microstructural properties (grain size, lattice parameter and texture) were evaluated by XRD. The TiN deposition rates and film resistivities were also determined. Finally the film properties of the TiN barriers as determined by surface analysis were related to the process parameters.