DNA-mediated Surface Reactions

在这项由化学系高分子、超分子和纳米化学计划资助的项目中，匹兹堡大学的刘海涛教授正在开发一种基于DNA纳米技术的新光刻方法。光刻技术被用来制造用于个人电脑和手机的集成电路。然而，传统的光刻技术正在接近其受光衍射限制的分辨率极限。该项目将开发一种基于DNA的光刻技术，通过利用DNA纳米结构的可编程性来实现高分辨率和低成本。此外，这笔助学金还将启动一个暑期研究计划，培训来自非博士授予机构的本科生。这个项目将检验这样一个假设，即DNA纳米结构中的局部化学环境(例如，碱基序列和化学修饰)可以有效地调节表面反应的速度，从而导致高分辨率的图案转移。这项工作旨在了解这种新的图案转移过程的化学机制，并在此基础上开发利用DNA纳米结构控制表面反应动力学的一般策略。通过改变DNA纳米结构模板的碱基序列和化学官能化程度来研究局部化学环境对反应动力学的影响。这些实验研究将与分子动力学模拟相结合，以提供对DNA纳米结构对活性前体的吸附及其在表面的后续反应的影响的分子尺度的了解。使用这里开发的化学，人们将能够以前所未有的分辨率制造任意形状的图案，分辨率低至10纳米以下。更重要的是，由于图案转移的机理广泛适用于超分子模板，总的来说，这项工作可能会对自下而上的纳米制造领域产生广泛的影响。

In this project funded by the Macromolecular, Supramolecular, and Nanochemistry Program of the Chemistry Division, Professor Haitao Liu of the University of Pittsburgh is developing a new lithography method based on DNA nanotechnology. Lithography is used to make integrated circuits such the ones used in personal computers and cellphones. However, conventional lithography is approaching its resolution limit imposed by light diffraction. This project will develop a DNA-based lithography that is both high resolution and low cost by exploiting the programmability of DNA nanostructures. In addition, this grant will also initiate a summer research program that will train undergraduate students from non-Ph.D. granting institutions. This project will test the hypothesis that the local chemical environment (e.g., base sequence and chemical modification) within a DNA nanostructure can effectively modulate the rate of surface reactions to result in high-resolution pattern transfer. The proposed work aims to understand the chemical mechanism of this novel pattern transfer process and based on which to develop a general strategy to control surface reaction kinetics using DNA nanostructures. The effect of local chemical environment on the reaction kinetics will be studied by varying the base sequence and the chemical functionalization of a DNA nanostructure template. These experimental studies will be coupled with molecular dynamics simulations to provide a molecular scale understanding of the effect of DNA nanostructure on the adsorption of reactive precursors and their subsequent reactions on the surface. Using the chemistry developed here, one will be able to fabricate arbitrary-shaped patterns with unprecedented resolution, down to sub-10 nm. More significantly, because the mechanism of the pattern transfer is widely applicable to supramolecular templates, in general, this work could have broad impact on the field of bottom-up nanofabrication.