Successive Spin Coating Induces an Order-Disorder Transition in a Block Copolymer Micellar Nanoarray

Controlling the spatial arrangement of nanodots is pivotal for functional nanomaterials and biointerfaces, and the spontaneous self-assembly of block copolymer micelles has been widely used to fabricate ordered nanostructures. However, achieving tunable disorder remains a fundamental challenge. Here, we demonstrate how successive spin coating dynamically modulates both density and disorder in micellar arrays, revealing an unexpected non-monotonic evolution of structural order. By using the Voronoi tessellation and Alpha shapes filtering algorithm, we found that initial coatings produce hexagonal order (interparticle distance: 126 nm, σ_d/d̅ = 0.12) and intermediate cycles induce maximal disorder (interparticle distance: 95 nm, σ_d/d̅ = 0.26), while further deposition partially restores order driven by steric hindrance (interparticle distance: 73 nm, σ_d/d̅ = 0.20). Our successive spin-coating approach achieves tunable disorder equivalent to conventional polymer-blending methods but without additives, offering a versatile strategy for engineering nanoscale surface patterns with potential applications for biomaterials and optical device design.