Three-dimensional deep sub-wavelength defect detection using λ = 193 nm optical microscopy.

Optical microscopy is sensitive both to arrays of nanoscale features and to their imperfections. Optimizing scattered electromagnetic field intensities from deep sub-wavelength nanometer scale structures represents an important element of optical metrology. Current, well-established optical methods used to identify defects in semiconductor patterning are in jeopardy by upcoming sub-20 nm device dimensions. A novel volumetric analysis for processing focus-resolved images of defects is presented using simulated and experimental examples. This new method allows defects as narrow as (16 ± 2) nm (k = 1) to be revealed using 193 nm light with focus and illumination conditions optimized for three-dimensional data analysis. Quantitative metrics to compare two-dimensional and three-dimensional imaging indicate possible fourfold improvements in sensitivity using these methods.

Glass transition of polymer-nanocrystal thin film mixtures: role of entropically directed forces on nanocrystal distribution.

The connection between the average properties of a polymer/nanocrystal hybrid material and the nanocrystal spatial distribution is shown. Specifically, a property such as the glass transition temperature, Tg, is shown to vary by as much as 65 degrees C through only changes in the spatial distribution of the nanocrystals. Considerable control can be exercised over the nanoparticle spatial distribution. In addition, we show that while the Tg of a thin film hybrid material may be enhanced in relation to the pure bulk system, the bulk nanocomposite analog shows a reduction in Tg. These findings have broad implications with regard to the design of materials with required properties.

Ordering transition of block copolymer films.

It is well-known that a bulk, symmetric, A-b-B diblock copolymer forms a lamellar morphology, with period L, below an order-disorder transition (T(ODT)) temperature, for chiN < 10.5; chi is the Flory-Huggins interaction parameter and N is the degree of polymerization of the copolymer. The ordering temperatures of poly(styrene-b-methyl methacrylate) (PS-b-PMMA) thin film diblock copolymers of thickness h