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This paper presents the results of a study to determine Young’s modulus, residual stress, and burst strength of polycrystalline 3C silicon carbide (poly-SiC) films grown on as-deposited and annealed polysilicon substrate layers. The biaxial modulus and residual stress were determined for bulk micromachined poly-SiC diaphragms using an interferometric load-deflection measurement apparatus. The load-deflection data were analyzed using a least-squares fitting technique to extract the biaxial modulus and residual stress values, and Young’s modulus was calculated assuming a Poisson ratio of 0.15. Poly-SiC films comprised of equiaxed grains exhibited Young’s modulus values ranging from 452 to 494GPa, while columnar films with a high degree of (110) texture exhibited Young’s modulus values between 340 and 357GPa. The residual stress for these films did not exhibit a discernable relationship with microstructure; however, the values exhibited a general dependence on growth temperature. Poly-SiC films grown at 1280 °C had residual stress values ranging from 401 to 486MPa, while a film grown at 1160 °C had a residual stress value of 113MPa. Burst strength was determined using a combination of finite element analysis and burst pressure measurements of the suspended diaphragms. Poly-SiC films grown at 1280 °C exhibited an average burst strength value of 1718MPa, while the poly-SiC film grown at 1160 °C had an average burst strength value of 1321MPa.

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New techniques recently developed at the National Institute of Standards and Technology using bright-field optical tools are applied to signal-based defect analysis of features with dimensions well below the measurement wavelength. A key to this approach is engineering the illumination as a function of angle and analysis of the entire scattered field. In this paper we demonstrate advantages using this approach for die-to-die defect detection metrology. This methodology, scatterfield optical microscopy (SOM), is evaluated for defect inspection of several defect types defined by Sematech on the Defect Metrology Advisory Group (DMAG) intentional defect array (IDA) wafers. We also report the systematic evaluation of defect sensitivity as a function of illumination wavelength.Theoretical simulations are reported that were carried out using a fully three-dimensional finite difference time domain (FDTD) electromagnetic simulation package. Comprehensive modeling was completed investigating angle-resolved illumination to enhance the detection of several defect types from the IDA wafer designs. The defect types covered a variety of defects from the IDA designs. The simulations evaluate the SOM technique on defect sizes ranging from those currently measurable to those the industry considers difficult to measure. The simulations evaluated both the 65 nm IDA metal-1 M1 trench and the polysilicon stack and more recent 13 nm linewidth logic cells.