An approach to sustainability evaluation and characterization of a C60-based device

Climate change has become an urgent global issue. Among the anthropic agents, the electronic industry has a significant impact on it, accounting to abount 0.45% of the global greenhouse gases emissions. Therefore it is interesting to evaluate the environmental footprint of this growing sector and possible alternatives to the current technologies, focusing on the semiconductor industry. In this context, the fullerene C60 is a well-documented molecule, constituting a well-known organic material, e.g., used in thin film. In this work, the C60 is investigated as potentially low-environmental impact organic material for the implementation of electronic devices. In particular, both a sustainability evaluation and a characterization of a microelectronic device is performed. The former is based on a proposed scheme focused on the environmental impact of the fabrication: from the synthesis of the material (12.7 GJ/Kg C60 and 48.55 L/Kg C60 of o-xylene loss) and the device fabrication ( 300 MJ of energy) up to the energy consumption during the usage. Concerning the second, both ab-initio computations and measurements on the fabricated structure have been employed, with a structure based on a top-gate bottom-contact thin film transistor with Bi as contact metal. The results brought to the definition of the energy band diagram, by comparing computed levels on the bulk structure with the photoelectron spectroscopy measurements and Kelvin probe scanning microscopy. The latter, together with atomic force microscopy, provided the roughness of the different uniform surfaces for both their potential distribution and topography. The obtained results motivate further analyses on metal-organic junction, oxide and fabrication process, posing the basis to the study of an optimized device capable to be competitive in the global market.