论文标题
链柔韧性对薄膜二嵌段共聚物自组装的影响
The Chain Flexibility Effects on the Self-assembly of Diblock Copolymer in Thin Film
论文作者
论文摘要
我们研究了链柔韧性对对称二嵌段共聚物（BCP）自组装行为的影响，当它们被限制为两个表面之间的薄膜时。采用类似蠕虫的链（WLC）自一致的野外理论，我们研究了并行（l $ _ {\ parallel} $）和垂直（l $ _ {\ perp} $）方向的相对稳定性，BCP层状阶段的方向是稳定性的，从而使稳定性从稳定性的goussian chains to semi-chains chains andi-semi-chains chains andirigiencation Chains andirigiencation Chains and Ind Ind Ind Indigience Chains Chains and Ind Indigion Chains Chains Chains Chainsirigible。对于平坦和中性的边界表面（对两个BCP组件之一没有表面偏好），L $ _ {\ perp} $ lamellae的稳定性随链刚度而增加。当顶部表面平坦并且底部底物瓦楞纸时，增加表面粗糙度会增强L $ _ {\ perp} $ lamellae的稳定性，用于柔性高斯链。但是，对于刚性链，观察到相反的行为，其中l $ _ {\ perp} $稳定性随着基板粗糙度的增加而降低。我们进一步表明，随着底物粗糙度的增加，基板偏好的临界值$ u^{*} $，对应于L $ _ {\ perp} $ - to-l $ _ {\ parallel} $过渡，刚性链减小，而固定链的较小链，而灵活的高斯链的固定链增加。我们的结果突出了定制薄膜设置中层状相的方向的物理机制。这特别是对于新兴纳米光刻和其他工业应用中需求较高的简短（半灵性或刚性）链，这一点很重要。
We investigate the effects of chain flexibility on the self-assembly behavior of symmetric diblock copolymers (BCPs) when they are confined as a thin film between two surfaces. Employing worm-like chain (WLC) self-consistent field theory, we study the relative stability of parallel (L$_{\parallel}$) and perpendicular (L$_{\perp}$) orientations of BCP lamellar phases, ranging in chain flexibility from flexible Gaussian chains to semi-flexible and rigid chains. For flat and neutral bounding surfaces (no surface preference for one of the two BCP components), the stability of the L$_{\perp}$ lamellae increases with chain rigidity. When the top surface is flat and the bottom substrate is corrugated, increasing the surface roughness enhances the stability of the L$_{\perp}$ lamellae for flexible Gaussian chains. However, an opposite behavior is observed for rigid chains, where the L$_{\perp}$ stability decreases as the substrate roughness increases. We further show that as the substrate roughness increases, the critical value of the substrate preference, $u^{*}$, corresponding to an L$_{\perp}$-to-L$_{\parallel}$ transition, decreases for rigid chains, while it increases for flexible Gaussian chains. Our results highlight the physical mechanism of tailoring the orientation of lamellar phases in thin-film setups. This is of importance, in particular, for short (semi-flexible or rigid) chains that are in high demand in emerging nanolithography and other industrial applications.
