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The self-assembly of block copolymers (BCPs) has attracted considerable attention because it can effectively generate highly ordered nanostructures through a simple and cost-effective process. However, in BCP annealing systems, there remain several challenges and issues that must be resolved to achieve more rapid and tunable pattern formation of BCPs with a high Flory–Huggins parameter (χ) for next-generation lithography applications. Here, we introduce a useful annealing technique to induce a rapid morphological transition of sphere-forming poly­(styrene-b-dimethylsiloxane) (PS-b-PDMS) BCPs by employing multistep solvent vapor annealing (MSVA) and a combined annealing process of solvent vapor annealing (SVA) and immersion annealing (IA). We successfully obtained well-ordered sub-20 nm line, dot, core–shell dot, and core–shell line structures with a short annealing time (<25 min) based on the synergetic effects of the combined annealing method which provides both the fast self-assembly kinetics and a wide range of pattern geometries. Furthermore, we demonstrate how the repeated process of SVA and IA affects the morphological stability of self-assembled BCPs, showing highly ordered solid and core–shell BCP nanostructures even after ten cycles of the repeated annealing process. We expect that these results will provide a new guideline to manipulate diverse BCP nanostructures effectively for nanodevice fabrication by combining various annealing methods.

Lead‐free (Na0.53K0.45Li0.02)(Nb0.8Ta0.2)O3 (NKLNT) was prepared using a conventional cold‐pressing method. A commercial piezoresponse force microscope (PFM) was applied to observe the domain structures of NKLNT ceramics. The typical configuration of the ferroelectric domain was analyzed in abnormal grains with grain sizes that exceeded 40 μm, where tetragonal 90° domains are predominant. The local piezoresponse hysteresis loops were characterized and studied as a function of the domain width (dw) in the range 300–1000 nm. It was found that the amplitude signals increased and the coercive field reduced significantly with a decrease in the domain size. Finally, the local longitudinal piezoelectric coefficient (d33) increased as the domain size decreased.

In contrast to the Pb-based magnetoelectric laminates (MELs), we find in the BaTiO3 and NiFe2O4 laminates (number of layers n=5–25) that the longitudinal magnetoelectric (ME) voltage coefficient αE33 becomes much larger than the transverse one due to preferential alignment of magnetic moments along the NiFe2O4 plane. Moreover, upon decreasing each layer thickness down to 15 µm, we realize enhanced αE33 up to 18 mV/(cm·Oe) and systematic increase of the ME sensitivity in proportion to n to achieve the largest in the Pb-free MELs (400×10-6 V/Oe), thereby providing pathways for tailoring ME coupling in mass-produced, environment friendly laminates.