Stabilizing ultrathin films, in particular avoiding dewetting, is critical to the application of polymer thin films from biology to electronics. To address this issue, a wide range of approaches have been developed, including self-assembled monolayers to modify surface energy, and covalent attachment methods, such as surface-initiated polymerization and grafting of end-functionalized polymers. However, most of these approaches either require postprocessing of the substrates or are applicable only to the specific combination of polymers and substrates. Herein, we introduce a mussel-inspired universal adhesive moiety, dopamine, as an end group for any polymer to promote film stability, and demonstrate its application to spinon doping on silicon, in particular. Leveraging the versatility of reversible addition−fragmentation chain transfer (RAFT) polymerization, the dopamine moiety is incorporated as an end group. Dopamine functionalized 15 nm thick films are more thermally stable at 230 °C on a variety of semiconductor-relevant surfaces (Si−OH, SiO x , TiN, and Si 3 N 4 ), while control polymer films with a carboxyl end group severely dewet. The dopamine end group also ensures successful sub-10 nm thick conformal coatings on three-dimensional surfaces, confirmed by crosssectional scanning transmission electron microscopy with electron energy loss spectroscopy (STEM-EELS). Furthermore, as a polymeric spin-on doping material, dosage of dopant with the dopamine-functionalized polymer is comparable or higher than that with the control end group, demonstrating one of the promising applications of such conformal coatings.

The selective deposition of polymer thin films can be achieved via spin coating by manipulating interfacial interactions. While this “spin dewetting” approach sometimes generates spatial localization on topographic and chemical patterns, the connection between material selection, process parameters, and resulting film characteristics remains poorly understood. Here, we demonstrate that accurate control over these parameters allows incomplete trichlorosilane self-assembled monolayers (SAMs) to induce spin dewetting on both homogeneous (SiO2) and heterogeneous (Cu/SiO2 or TiN/SiO2) surfaces. Glassy polymers undergo a sharp transition from uniform wetting to complete dewetting depending on spin speed, solution concentration, polymer molecular weight, and SAM chemistry. Under optimal conditions, spin dewetting on line–space patterns results in the selective deposition of polymer over regions not functionalized with SAM. The insights described herein clarify the importance of different variables involved in spin dewetting and provide access to a versatile strategy for patterning polymeric thin films.

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Block copolymer (BCP) self-assembly-assisted doping for semiconductors is used to achieve discrete doping with nanometer-scale junction depth, high throughput, and large area coverage. As devices become smaller and more sophisticated, spatial control of dopants becomes more critical. A variety of doping methods, such as monolayer doping and 𝜹-doping, have been developed to replace the conventional doping method, ion-implantation; however, lateral patterning of dopants relies on photo-or e-beam lithography. To address these challenges, a self-assembling dopant (boron)-containing BCP is designed to directly pattern dopants on the nanometer scale. This method skips the lithography step and is compatible with directed self-assembly approaches. The effect of the boron concentration in the BCP on the doping performance is systematically studied by changing the volume fraction of the boron-containing block while keeping the domain spacing and the mesoscale morphology constant. Successful self-assembly of the BCP into a hexagonally packed cylindrical morphology is confirmed by small-angle X-ray scattering and resonant soft X-ray scattering with a 26 nm cylinder-to-cylinder distance. Doping silicon using these BCPs enables discrete doped areas with shallow (7-13 nm) junction depth as demonstrated by the depth profile of boron, and supported by a sheet resistance study.

Processes that enable selective deposition in thin films are desired for advanced patterning applications to reduce overlay demands, but conventional techniques are slow and limited in material scope. Here, we report a method that selectively deposits polymeric coatings on heterogeneous substrates (Cu/SiO2) using spin coating. Unlike traditional approaches that rely on surface pretreatments, herein, selectivity is induced by polymer design that promotes preferential dewetting from one substrate material and uniform wetting on the other. As evidenced by studies with homogeneous surfaces, poly­(acrylates) containing semifluorinated pendant groups satisfy this criterion and spontaneously dewet from SiO2 but form continuous films on Cu. When spin coated onto Cu/SiO2 line–space patterns, these semifluorinated polymers selectively coat only the Cu lines without any pre- or postprocessing. Rational design rules have been elucidated that anticipate regimes of selective deposition by correlating the droplet size of dewetted features on homogeneous SiO2 with the dimensions of heterogeneous Cu/SiO2 patterns. The universality of this unique strategy is demonstrated across a library of polymers with varying molecular weights and monomer structures, providing significant advances arising from the simplicity and rapidity of spin coating. For 10–40 μm full pitch features, the entire deposition procedure involves a single step and is complete in under 1 min.