Top-down versus bottom-up

E24.30 (a) Top-down versus bottom-up. The top-down approach requires one to carve out nanoscale features from a larger object. The bottom-up approach requires one to build up nanoscale features from smaller entities. Lithography is a standard approach to top-down and thin film deposition of quantum wells or superlattices is a standard approach to bottom-up. ... 

Material Synthesis Top-down versus Bottom-up Approaches... 

Tour, J.M. (2014) Top-down versus bottom-up fabrication of graphene-based electronics. Chem. Mater., 26, 163-171. 

KelleherNL, Lin HY, Valaskovicm GA, Aserud DJ, Fridriksson EK, McLafiferty FW. Top-down versus bottom-up protein characterization by tandem high-resolution mass spectrometry, J Am Chem Soc. 1999 121 806-12. 

I discuss a number of features of world-wide science curriculum development, including the extent to which each development is local and specific, the relationship to issues and ideologies current at the time, the question of top-down versus bottom-up development, the role of didactic inventions and creativity, the relationship of development to research, and the question of ownership. 

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