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Ultra large‐scale integration (ULSI) should lead to 100 nm production circuits by 2006 as predicted by the Semiconductor Industry Association (SIA). For sub‐100 nm lithography it is desirable to synthesize higher performance and higher contrast resists. An optimum combination of high contrast necessary for sub‐100 nm resolution, high sensitivity for high throughput can be achieved by carefully engineering organic–inorganic nanocomposites, acting as optimum resists for a given lithographic process. This review outlines emerging approaches towards the achievement of these goals. A section also highlights selected state‐of‐the‐art organic resists. Nanocomposite resists for sub‐100 nm features have included the incorporation of fullerene C60 in a commercial resist ZEP520 (see Figure). Alternatively, nanoscale silica particles were incorporated in the polymer backbone as covalently bonded pendant clusters. The dispersion of 8–10 nm silica particles in a chemically amplified resist has also been reported. In all these approaches, a higher softening temperature (Tg) and increased rigidity, due to increased density of the film resulted. Higher etch resistance as well as increased mechanical properties and also enhanced resist performance for nanometer pattern fabrication have been obtained in these nanocomposites. Alternative approaches to conventional lithography, based on self‐assembled nanostructures, incorporating inorganic features as well as nanoimprinting via silicon polymer precursors, are also discussed.

The energy dependence of forward pion double charge exchange reactions on light nuclei is studied for both the Ground State transition and the Double-Isobaric-Analog-State transitions. A common characteristic of these double reactions is a resonance-like peak around 50 MeV pion lab energy. This peak arises naturally in a two-step process in the conventional pion-nucleon system with proper handling of nuclear structure and pion distortion. A comparison among the results of different nuclear structure models demonstrates the effects of configuration mixing. The angular distribution is used to fix the single particle wave function. PACS: 25.80Gn, 24.10Ht,21.60Fw

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