Towards Ordered Silicon Nanostructures through Self‐Assembling Mechanisms and Processes

Abstract

The design and development of innovative architectures for memory storage and energy conversion devices are at the forefront of current research efforts driving us towards a sustainable future. However, issues related to the cost, efficiency, and reliability of current technologies are still severely limiting their overtake of the standard designs. The use of ordered nanostructured silicon is expected to overcome these limitations and push the advancement of the alternative technologies. Specifically, self-assembling of block copolymers has been recognized as a promising and cost-effective approach to organize silicon nanostructures. This work reviews some of the most important findings on block copolymer self-assembling and complements those with the results of new experimental studies. First of all, a quantitative analysis is presented on the ordering and fluctuations expected in the synthesis of silicon nanostructures by using standard synthesis methods like chemical vapour deposition. Then the effects of the several parameters guiding the ordering mechanisms in the block copolymer systems, such as film thickness, molecular weight, annealing conditions, solvent, and substrate topography are discussed. Finally, as a proof of concept, an in-house developed example application to solar cells is presented, based on silicon nanostructures resulting from self-assembling of block copolymers.

Environmental justification for the use of solar panels and batteries as an alternative energy source

“…The flow of sunlight is received by the element to electrically in the daytime, producing a certain amount of energy in accordance with the type of design of the panels [6]. The battery receives the resulting energy, accumulation occurs until it fills its capacity to a full charge.…”

Silicon Quasi‐One‐Dimensional Nanostructures for Photovoltaic Applications

“…Inside this range of temperature, the self-assembling process can be tuned in order to obtain ordered hexagonal macrodomains as large as microns [53]. The template replication down to the SiO 2 and then to the Si substrate to form NHs can be carried by a CHF 3 /Ar gas mixture followed by cycling SF 6 /O 2 and CHF 3 /Ar according to the procedure of the Bosch process [54]. The choice about the gases mixture and the general approach for both the etching cycles is made in order to promote the anisotropic etching which removes material from the bottom of the structures realized while it protects the sidewall and preserves them from the etching.…”

Atomically Architected Silicon Pyramid Single-Crystalline Structure Supporting Epitaxial Material Growth and Characteristic Magnetism

“…Because the size of a sample is geometrically constrained to a nanometer length scale, at least in one of the three dimensions, disordered atomic arrangements significantly degrade the physical properties or induce deviation from an ideal value. On the other hand, the synthesis of a 3D structured sample via a wet chemical reaction 22 limits the range of producible shapes and has poor controllability in terms of the arrangement and positioning, even though physical damage due to dry etching can be prevented.…”