Nanostructure fabrication by direct electron-beam writing of nanoparticles

Direct additive-layer fabrication of nanostructures is a widely sought goal, which is not possible using traditional layered resist optical and electron-beam lithographic techniques. However, recently, it has been shown that certain metallic and semiconducting nanoparticles capped with protective organic groups are promising "inklike" resist materials for patterning a variety of electronic and mechanical structures [C. A. Bulthaup et al., Appl. Phys. Lett. 79, 1525 (2001)]. Several groups have successfully patterned single-layer gold nanoparticle films by means of direct electron-beam writing [X. M. Lin, R. Parthasarathy, and H. M. Jaeger, Appl. Phys. Lett. 78, 1915 (2001); T. R. Bedson, R. E. Palmer, T. E. Jenkins, D. J. Hayton, and J. P. Wilcoxon, Appl. Phys. Lett. 78, 1921 (2001); L. Clarke et al., Appl. Phys. Lett. 71, 617 (1997)]. In this work, we apply these materials in a new lithographic mode, using an electron beam to cause direct sintering of these 2-10 nm nanoparticles, building structures of multiple layers and multiple materials with linewidth resolutions of 80-100 nm. (C) 2002 American Vacuum Society.