Research Objectives: A Multi-University/Industry/NIST team will address the development and integration of mesoporous, ultra-low dielectric constant films for semiconductor devices. Continuation of the historical trend of reduced device dimensions requires materials with dielectric constants (k) of less than 2.4 that can survive the structural and mechanical demands of integration. Moreover, at dimensions less than 70 nm, techniques that offer control over long range order, pore orientation and patterning at multiple length scales are required for practical integration schemes. A new approach offers these possibilities. The technique involves the infusion and selective condensation of metal oxide precursors within one domain of highly ordered block copolymer templates using supercritical (SC) carbon dioxide as the reaction medium. The template is then removed to produce the mesoporous oxide. By separating template preparation from oxide condensation, the block copolymer architecture can be manipulated at the local level by domain orientation and alignment using surface and external fields and at the device level by lithographic patterning prior to precursor infusion. Watkins (UMass) will coordinate the NIRT Team and lead the development of highly ordered mesoporous films in SC CO2. Ober (Cornell) will lead the development of templates for direct patterning by photolithography. Burkett (Amherst College) will characterize film structure and composition using solid state NMR. Maroudas (UMass) will develop models to relate film architecture to mechanical properties. Lin (NIST) will lead the development of new metrology tools for the analysis of patterned, highly ordered films. Schulberg from Novellus Systems, a leading semiconductor equipment company, will lead process development and scale-up efforts to full process wafers (200 and 300 mm) and develop post-processing strategies and integration schemes.
Broad Impact: Successful preparation of viable low k films will have an enormous near term impact on semiconductor manufacturing, a $100 billion/yr industry. The approach also provides a realizable technology platform for other metal oxide nanostructures including sensors, photonic materials, data storage arrays and separation media. Throughout the program, postdoctoral fellows, graduate and undergraduate students will acquire fundamental skills in a multidisciplinary environment that fosters an awareness of the demands of technology implementation. The partnership of a diverse team of PIs from Universities, Colleges, and Industry provides important opportunities for mentoring women and undergraduates from four-year institutions and advanced training of post-docs at the University/National Laboratory interface.
