“Bottoms-up Nanoscale Design”   Ion Beam Lithography “Bottoms-up Nanoscale Design” Brian Ellis First investigated by Goodenough in 1987, Lithium metal phosphate offer a good solution for the problems faced. Due to the inductive effects of the bulky phosphate groups, the potential of the (Fe2+/Fe3+) couple is raised relative to the Standard Oxide making this a structure very attractive possibility It is a Light, benign and relatively inexpensive Material with a good electrode potential compared to graphite It is Non-Hygroscopic and the bulky phosphate groups also offer a stable framework which remains intact during cycling

Lithography Process Replication of a master pattern onto a substrate Coat the substrate with a radiation-sensitive polymer film (a resist) Expose specific area of film to radiation, which alters properties (solubility) of film First investigated by Goodenough in 1987, Lithium metal phosphate offer a good solution for the problems faced. Due to the inductive effects of the bulky phosphate groups, the potential of the (Fe2+/Fe3+) couple is raised relative to the Standard Oxide making this a structure very attractive possibility It is a Light, benign and relatively inexpensive Material with a good electrode potential compared to graphite It is Non-Hygroscopic and the bulky phosphate groups also offer a stable framework which remains intact during cycling

Ion Beam Lithography (IBL) Ion beams: H+, He+, Ga+ Several implementations: Focused IBL (direct writing) Masked IBL (beam passes through ion-transparent membrane, patterned with absorber material, positioned close to coated substrate) Resists: Polymethylmethacrylate (PMMA) is most common, Poly(butene-1-sulfone), Poly(2,2,2-trifluoroethyl-α-chloroacrylate) Penetration of the particle beam is small, compared to electron beam reduce blurring resulting from beam scattering (reduce proximity effect; increase localization, precision) First investigated by Goodenough in 1987, Lithium metal phosphate offer a good solution for the problems faced. Due to the inductive effects of the bulky phosphate groups, the potential of the (Fe2+/Fe3+) couple is raised relative to the Standard Oxide making this a structure very attractive possibility It is a Light, benign and relatively inexpensive Material with a good electrode potential compared to graphite It is Non-Hygroscopic and the bulky phosphate groups also offer a stable framework which remains intact during cycling

Ion Beam (H+, He+) Ionization region: plasma formed Potential placed at extraction region removes ions from chamber J. Melngailis et al. J. Vac. Sci. Tech. 16 (1998), 927.

Gallium Ion Beam Ion source: tungsten wetted with gallium Ion extraction is observed by applying 5-7 kV (VEXT) Aperatures focus beam Deflector directs the beam onto substrate <1000 Å spots can be obtained R. L. Kubena et al. App. Phys. Lett. 34 (1979), 310.

Etching a Gold Substrate R. L. Kubena et al. J. Vac. Sci. Tech. 16 (1979), 1610. First investigated by Goodenough in 1987, Lithium metal phosphate offer a good solution for the problems faced. Due to the inductive effects of the bulky phosphate groups, the potential of the (Fe2+/Fe3+) couple is raised relative to the Standard Oxide making this a structure very attractive possibility It is a Light, benign and relatively inexpensive Material with a good electrode potential compared to graphite It is Non-Hygroscopic and the bulky phosphate groups also offer a stable framework which remains intact during cycling