High Resolution Nanofabrication


High Resolution Nanofabrication

Georgiev, Y. M.

Nanofabrication aims at creating structures and devices having minimum dimensions below 100 nm. This is possible to achieve in two main ways: bottom-up and top-down. In the former, the structures and devices are created from small to large in an additive fashion, which relies to a great extent on self-organisation processes. In the latter, the fabrication goes from large to small where nano-structures and devices are carved from a larger piece of material in a subtractive fashion. The top-down approach is much more mature than the bottom-up one and is based on two long-established processes: (i) nanolithography, where a stencil with the required pattern is created in a sacrificial layer called “resist”, deposited on the main working material (substrate), and (ii) pattern transfer through the resist stencil into the base material.
In this paper we will present results on high-resolution nanofabrication of structures and devices with critical dimensions (CD) below 10 nm on silicon (Si), silicon-on-insulator (SOI), germanium (Ge) and germanium-on-insulator (GeOI) substrates. The fabrication was mainly within the frames of the top-down approach and was based on electron beam lithography (EBL) with positive or negative resists followed by a pattern transfer with both additive (metal deposition and lift-off) and subtractive (dry etching) methods.[1-4] Moreover, high-end results on combination of bottom-up and top-down approaches will also be presented such as (i) contacting of bottom-up grown and randomly distributed nanostructures for their integration into functional devices [5] as well as (ii) pattern density multiplication by directed self assembly (DSA) of block-copolymers (BCP).[6,7] We believe that these results are showing some of the promising trends for future development of high-resolution nanofabrication.
References:
[1] Küpper, D., Küpper, D., Wahlbrink, T., Bolten, J., Lemme, M. C., Georgiev, Y. M., & Kurz, H. (2006). Megasonic-assisted development of nanostructures. Journal of Vacuum Science & Technology B: Microelectronics and Nanometer Structures, 24(4), 1827.
[2] Georgiev, Y. M., Petkov, N., McCarthy, B., Yu, R., Djara, V., O’Connell, D., … Holmes, J. D. (2014). Fully CMOS-compatible top-down fabrication of sub-50nm silicon nanowire sensing devices. Microelectronic Engineering, 118, 47-53.
[3] Gangnaik, A., Georgiev, Y. M., McCarthy, B., Petkov, N., Djara, V., & Holmes, J. D. (2014). Characterisation of a novel electron beam lithography resist, SML and its comparison to PMMA and ZEP resists. Microelectronic Engineering, 123, 126-130.
[4] Gangnaik, A. S., Georgiev, Y. M., Collins, G., & Holmes, J. D. (2016). Novel germanium surface modification for sub-10 nm patterning with electron beam lithography and hydrogen silsesquioxane resist. Journal of Vacuum Science & Technology B, Nanotechnology and Microelectronics: Materials, Processing, Measurement, and Phenomena, 34(4), 041603.
[5] Teschome, B., Facsko, S., Schönherr, T., Kerbusch, J., Keller, A., & Erbe, A. (2016). Temperature-Dependent Charge Transport through Individually Contacted DNA Origami-Based Au Nanowires. Langmuir, 32(40), 10159-10165.
[6] Cummins, C., Gangnaik, A., Kelly, R. A., Borah, D., O'Connell, J., Petkov, N., … Morris, M. A. (2015). Aligned silicon nanofins via the directed self-assembly of PS-b-P4VP block copolymer and metal oxide enhanced pattern transfer. Nanoscale, 7(15), 6712-6721.
[7] Cummins, C., Gangnaik, A., Kelly, R. A., Hydes, A. J., O’Connell, J., Petkov, N., … Morris, M. A. (2015). Parallel Arrays of Sub-10 nm Aligned Germanium Nanofins from an In Situ Metal Oxide Hardmask using Directed Self-Assembly of Block Copolymers. Chemistry of Materials, 27(17), 6091-6096.

Related publications

  • Invited lecture (Conferences)
    5th International workshop “Nano-Fabrication, Devices & Metrology”, 19.-20.06.2017, Eindhoven, The Netherlands

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Publ.-Id: 26808