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Low κ Organosilicate Glass (OSG) films are being proliferated into new IC device architectures with CMP requirements spanning a wide range (highly selective to non-selective, low polish rates to high polish rates). This study aims to understand the relationship between these OSG film properties (both bulk and surface) and their planarization response, especially removal rate (RR). Eight OSG films were polished along with TEOS oxide using two barrier slurries. The films ranged in carbon content from 8 to 24 % and in nanoindentation elastic modulus from 5.5 to 21.8 GPa. Counterintuitively, higher mechanical strength (i.e., hardness, elastic modulus) of the low κ film did not result in lower polish rates; but was in agreement with previously noted behavior [1]. Removal rates also did not correlate to key OSG film properties such as refractive index (RI), dielectric constant (κ), or total carbon content (by X-ray photoelectron spectroscopy). However, an inverse relationship was observed between RR and the bulk chemical bonding structure (Si-CH3/Si-O ratio) as determined by transmission infrared spectroscopy (FT-IR) measurements (see Figure 1). In addition, a correlation between RR and OSG film’s surface free energy post-polish (measured from water and diiodomethane contact angles) was also observed. Based on the above findings, a mechanistic understanding of low κ OSG polishing was developed. [1] L. Matz, M. Haas, M. O’Neill, R. Sawayda, A. Meyers, in Advanced Metallization Conference (AMC) (eds A. J. McKerrow, Y. Shacham-Diamand, S. Shingubara and Y. Shimogaki), Materials Research Society, Warrandale, PA, 463 (2009) Figure 1

Dense electrolyte films ∼15 μm thick made of samarium-doped ceria (SDC) are fabricated by spin-coating. The SDC powders are synthesized by the glycine nitrate combustion process. It is found that nanoscale SDC powders can be obtained at 1000 °C. Cells constructed with an SDC electrolyte, a NiO + SDC composite anode, and an SSC–SDC/SSC bi-layer cathode are fabricated and tested at temperatures from 400 to 650 °C. SEM micrographs show that the SDC electrolyte layer adheres well to the porous anode and the cathode. The maximum power densities of the cell are 38, 84, 185, 303, 438, and 549 mW cm −2 at 400, 450, 500, 550, 600, and 650 °C, respectively. Analysis of the impedance spectra indicates that the electrode polarization dominates the total cell resistance at temperatures below 550 °C, and the ohmic resistance dominates the total cell resistance above 550 °C. The activation energies of the resistances show that the cell performance is significantly controlled by the electrode polarization resistance. Durability tests are performed over 950 h and indicate that the power density and the voltage gradually degrade with time at a rate of ∼0.03 mW cm −2 h −1 and ∼0.07 mV h −1 , respectively. Hence, a low-temperature solid oxide fuel cell has been developed.

The Sm 0.5 Sr 0.5 CoO 3− δ (SSC) with perovskite structure is synthesized by the glycine nitrate process (GNP). The phase evolution of SSC powder with different calcination temperatures is investigated by X-ray diffraction and thermogravimetric analyses. The XRD results show that the single perovskite phase of the SSC is completely formed above 1100 °C. The anode-supported single cell is constructed with a porous Ni–yttria-stabilized zirconia (YSZ) anode substrate, an airtight YSZ electrolyte, a Sm 0.2 Ce 0.8 O 2− δ (SDC) barrier layer, and a screen-printed SSC–SDC composite cathode. The SEM results show that the dense YSZ electrolyte layer exhibits the good interfacial contact with both the Ni–YSZ and the SDC barrier layer. The porous SSC–SDC cathode shows an excellent adhesion with the SDC barrier layer. For the performance test, the maximum power densities are 464, 351 and 243 mW cm −2 at 800, 750 and 700 °C, respectively. According to the results of the electrochemical impedance spectroscopy (EIS), the charge-transfer resistances of the electrodes are 0.49 and 1.24 Ω cm 2 , and the non charge-transfer resistances are 0.48 and 0.51 Ω cm 2 at 800 and 700 °C, respectively. The cathode material of SSC is compatible with the YSZ electrolyte via a delicate scheme employed in the fabrication process of unit cell.

The possibility of eliminating finger or vermicular growth of α-Al2O3 particles obtained by calcination of boehmite was examined. Heterogeneous precipitation of boehmite in a well-dispersed θ-Al2O3 suspension was first prepared, in which the mass ratio of boehmite to θ-crystallite was evaluated to form agglomerates of similar sizes that will form α-Al2O3 crystallites of

Cationic additives are generally used in coated inkjet printing paper to improve water fastness. This study develops a coating for photographic inkjet printing paper that achieves good water fastness without cationic additives. Porous χ- Al 2 O 3 flake powder, which has high porosity, high specific surface area, and positive surface charges, is used as a pigment in the coating. The water fastness of prints is evaluated using an immersion method combined with the measurement of light absorbance of the water used for immersion. The results indicate that water fastness can be improved by introducing χ- Al 2 O 3 powder into the coating pigments. The intrinsic crevices and pores of χ- Al 2 O 3 provide concave sites for dye colorants and enhance the sorbtion of liquid phase of inks, but stick the dye colorants on the pigment surface. Furthermore, the positive surface charge of χ- Al 2 O 3 provides cationic sites for the fixation of dye on the coating surface via electrostatic interactions.