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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

The anode-supported solid oxide fuel cells (SOFCs) with an yttria-stabilized zirconia (YSZ) electrolyte have been successfully prepared by the sequential steps of fabricating technique including tape casting, spin coating, and screen-printing. Two types of the SOFCs are manufactured and their cell performances are characterized via the detail analysis of the electrochemical impedance spectroscopy (EIS). The maximum power densities are 411 and 289 mW/cm 2 for the high and low performance cells at 800°C, respectively. According to the EIS analysis, the electrochemical performance of the poor cell is dominated by the anodic non-charge-transfer resistance, which is mainly resulted by the gas diffusion polarization due to the low porosity of the anode. The high performance cell is controlled by the simultaneous contributions of the ohmic resistance (R O ), the anodic polarization (R AP ), and the cathodic polarization (R CP ) at the operation temperature of 800°C. However, the R CP will dominate the performance of the cell as the temperature is lowered down to 700°C.