Materials World Network: Triblock Terpolymers for Self-Assembled Nanolithography

二嵌段共聚物自组装成周期性阵列的微区的特征尺寸通常为10-50纳米，并已被用作自组装？反抗吗以限定可用于制造各种器件的周期性图案，所述器件例如硅电容器和晶体管、光子晶体和图案化磁介质。然而，二嵌段共聚物中的层状、圆柱形或球形微区通常形成具有六方对称性的光栅图案或密堆积结构。这限制了它们的器件应用，使得期望创建具有更宽范围的几何形状和应用的自组装图案。为了克服这一限制，马萨诸塞州理工学院（MIT）和英国布里斯托大学之间的这一合作项目将开发三嵌段三元共聚物，其形成具有各种几何形状的薄膜。工作包括设计三嵌段三元共聚物，以形成具有特定几何形状的膜，例如宽或密间隔的线，具有特定边缘调制的线，结或弯曲，或非紧密堆积排列的圆柱体或球体阵列;合成具有适当嵌段化学，相互作用和体积分数的聚合物;理解加工效应，包括衬底处理和退火过程;模拟自组装;以及在一个嵌段内产生磁性纳米颗粒以直接形成功能性纳米结构。本项目的核心是利用基底化学和形貌学研究三嵌段共聚物的模板化，从而引导自组装达到纳米级精度。学生将在国际环境中接受培训和指导，包括三嵌段共聚物的合成化学、嵌段共聚物光刻和模板化以及功能性纳米结构的制造。研究人员将合作开发教学材料，包括关于自我组装的讲座和演示，并通过学校和社区学院的推广和使用麻省理工学院开放式课程计划等资源将这项工作传播给广大受众。

Diblock copolymers self-assemble into periodic arrays of microdomains with feature sizes of typically 10-50 nm, and have been used as self-assembled ?resists? to define periodic patterns useful in making a wide range of devices such as silicon capacitors and transistors, photonic crystals, and patterned magnetic media. However, the lamellar, cylindrical or spherical microdomains in diblock copolymers generally form grating patterns, or close-packed structures with hexagonal symmetry. This restricts their device applications, making it desirable to create self-assembled patterns with a wider range of geometries and applications. To overcome this limitation, this collaborative project between the Massachusetts Institute of Technology (MIT) and the University of Bristol in the United Kingdom will develop triblock terpolymers which form thin films with a diverse range of geometries. The work includes design of triblock terpolymers to form films with specific geometries such as widely or closely-spaced lines, lines with specific edge modulations, junctions, or bends, or arrays of cylinders or spheres in non-close-packed arrangements; synthesis of polymers with appropriate block chemistry, interactions and volume fractions; understanding processing effects including substrate treatment and annealing processes; modeling the self-assembly; and generation of magnetic nanoparticles within one block to form functional nanostructures directly. Central to this work is an investigation of templating of triblock terpolymers using substrate chemistry and topography, so that the self-assembly can be guided to nanoscale precision.Students will be trained and mentored in an international setting, including the synthetic chemistry of triblock terpolymers, block copolymer lithography and templating, and the fabrication of functional nanostructures. The investigators will collaborate on developing teaching materials including lectures and demonstrations on self-assembly, and on dissemination of this work to a wide audience through school and community college outreach and use of resources such as the MIT OpenCourseWare initiative.