DMREF: Rapid Design and Engineering of Materials Systems for Nanomanufacturing via Directed Self-Assembly

嵌段共聚物是一种特殊形式的聚合物，通过简单地将两种不同类型的聚合物链连接在一起而制成。这些有趣的材料自然呈现出复杂的纳米结构形态，并在有机太阳能电池、水净化过滤器、发电燃料电池和半导体器件制造等方面具有潜在的应用前景。这种纳米结构的形态是共聚物中不同类型的聚合物链试图彼此分离的结果，就像油和水不喜欢混合一样，这一过程被称为相分离。为了在许多应用中发挥作用，这些嵌段共聚物必须用作薄膜，并且必须仔细控制不同聚合物相的位置和取向。目前对这种材料和工艺的了解有限，这使得设计和使用这些迷人的纳米结构材料变得困难。该项目的目标是开发一套设计工具和方法，以实现嵌段共聚物和界面涂层的快速设计，从而能够生产高度有序的纳米结构有机材料。使用的一般方法将结合详细的分子建模工具和精心选择的实验研究，以形成材料和工艺设计循环，从而实现比目前可能的材料设计周期明显更快的材料设计周期。定向自组装(DSA)方法提供了利用嵌段共聚物薄膜与异质图案化界面的相互作用来引导嵌段共聚物微相以长程有序的方式组装成所需取向的可能性。目前该领域的努力依赖于耗时且昂贵的实验研究，以确定能够实现有序纳米级结构的材料和工艺条件。此外，到目前为止，大多数工作都集中在聚(苯乙烯)-b-聚甲基丙烯酸甲酯嵌段共聚物上，其中两个聚合物嵌段表现出非常相似的性质。一般来说，人们感兴趣的是具有非常不同性质的嵌段、包含有用的功能性质并且可以获得较小相分离结构域尺寸的嵌段共聚物。在这个项目中，将开发新的嵌段共聚物，它可以实现更小的特征尺寸，并且具有有用的功能特性。此外，新的介观分子动力学模型可以准确地再现现实嵌段共聚物的性质和行为，将与详细的实验研究相结合，为这些新的嵌段共聚体系开发出良好的参数化模型。这种建模能力将形成一种新的快速方法的核心，用于设计使用DSA与这些新聚合物生产有序薄膜所需的界面导向层。这些模型将用于探索和绘制此类系统的行为和流程窗口，以便快速开发DSA制造流程。

Block copolymers are a special form of polymer made by simply joining two different types of polymer chains together. These interesting materials naturally exhibit complex nanostructured morphologies and have potential uses in a wide range of applications including organic solar cells, water purification filters, fuel cells for power production, and semiconductor device fabrication. This nanostructured morphology is the result of the different types of polymer chains in the copolymer trying to separate from one another much like oil and water do not like to mix, a process referred to as phase separation. To be useful in many applications, these block copolymers must be used as thin films and the location and orientation of the different polymer phases must be carefully controlled. Current understanding of such materials and processes is limited, which makes designing and using these fascinating nanostructured materials difficult. The goal of this project is to develop a set of design tools and methodologies that will allow for the rapid design of block copolymers and interfacial coatings that can enable production of highly ordered nanostructured organic materials. The general approach to be used will combine detailed molecular modeling tools with carefully selected experimental studies to form a material and process design loop that can result in significantly faster material design cycles than are currently possible.Directed self-assembly (DSA) methods offer the possibility to use the interaction of a block copolymer thin film with heterogeneous patterned interfaces to guide assembly of the block copolymer microphases into desired orientations with long range order. Current efforts in the field rely on time consuming and expensive experimental studies to identify materials and processing conditions that can achieve ordered nanometer scale structures. Furthermore, most work thus far has focused on poly(styrene)-b-poly(methyl methacrylate) block copolymers in which both polymer blocks exhibit very similar properties. In general, there is interest in block copolymers that possess blocks with very different properties, contain useful functional properties, and which can achieve smaller phase separated domain sizes. In this project, new block copolymers that can achieve much smaller feature sizes and which possess useful functional properties will be developed. In addition, a new meso-scale molecular dynamics model that can accurately reproduce the properties and behavior of realistic block copolymers will be coupled to detailed experimental studies to develop well parameterized models for these new block copolymer systems. This modeling capability will form the core of a new rapid methodology for designing the interfacial guiding layers required to produce ordered films using DSA with these new polymers. These models will be used to explore and map the behavior and process windows for such systems so that DSA manufacturing processes can be rapidly developed.