Resumen de Directed self-assembly of block copolymers on chemically nano-patterned surfaces /
The thesis entitled “Directed self-assembly of block copolymers on chemically nano-patterned surfaces”, aboard the challenge of the development, implementation and characterization of a chemical epitaxy process to direct self-assemble block copolymers. The development of this nanofabrication method contributes to the next generation of nanoelectronic devices and circuits. Firstly, the main aspects of directed self-assembly of block copolymers and its role and status in the future of nanoelectronics is presented and compared with other powerful technologies. Then, a general overview about the physics and chemistry involved in block copolymer thin films is presented, in order to understand and determine the interactions taking place during the DSA process.
The main part of the thesis is focused on the study, development and implementation of a chemical epitaxy approach to guide the self-assembly of block copolymers. Apart from the process development, the mechanisms which drive the block copolymer alignment are characterized and simulated into a DSA model. Moreover, the process transfer to a more industrial pilot line is presented.
The implementation of the chemical epitaxy process is addressed not only with commercial block copolymers, but also with new polymer systems which allow getting sub- 10 nm resolution. For these systems, a new guiding method is presented based on the combination of a chemical and graphoepitaxy approach.
To better understand the DSA process, dedicated metrology methods are also studied. In particular, by using high-energy X-ray techniques it is possible to describe the main characteristics of the chemical guiding patterns. On the other hand, the nanomechanical properties of block copolymer domains are studied by using the peak force tapping mode in atomic force microscopy.
A reliable method to pattern transfer the block copolymer features into the substrate is showed. It is based on infiltrating one block copolymer domain and enhancing thus, its resistivity to plasma etching. Finally, as a final application, a novel fabrication process of a nanowire mechanical resonator by means of DSA and infiltration is presented.
