SemiSynBio: Collaborative Research: DNA-based Electrically Readable Memories

几十年来，工程师们一直致力于开发一种低成本、可靠、高密度和非易失性的通用存储器技术。理想情况下，这种技术可以快速写入，读取或擦除，并且可以在任何定义的状态下无限期地持续。然而，目前的技术具有有限的寿命，通常难以写入，消耗大量的功率，并且无法维持当前的全球数据增长。另一方面，生物系统在数十亿年前就解决了这个问题，使用脱氧核糖核酸（DNA）结合酶方法来阅读、写入和擦除数据。事实上，人类平均每天写入40 EB的数据，而消耗的能量相对较少。而且，这些数据可以存储数百年或数千年。因此，DNA代表了为下一代电子设备开发存储器技术的独特而有趣的平台。然而，为了利用其惊人的存储能力，并成为一个可行的内存技术竞争者，一些重要的技术和基本的障碍必须检查和克服。作为实现这一目标的第一步，该提案旨在创建一种基于DNA的只读存储器（ROM），该存储器可以根据需要进行图案化，放置和编程，可以电读取，并且能够与传统的半导体电子器件进行长期数据存储和检索。为了实现这一目标，我们建立了一个多学科协作团队，致力于生物系统电气和计算机工程以及电荷传输物理学的联系。该团队在DNA纳米结构的控制和组装，纳米和分子电子系统以及纳米电子器件的理论和建模方面具有专业知识。该团队将与学生和初级研究人员一起工作，以了解和控制基于DNA的纳米结构的电荷传输特性，组装基于DNA的存储设备和电路，开发用于建模和编程这些系统的工具，并培养新一代能够在生物学和纳米/电气工程之间的接口工作的科学家和工程师。参与该项目的研究生将获得涉及电气工程，器件物理，化学，生物化学和材料科学的跨学科培训。此外，这个跨学科研究项目还与一个外展计划相结合，旨在扩大STEM领域代表性不足的少数民族和女学生的入学人数，为本科生提供研究经验，并向K-12学生介绍尖端的科学和工程问题。为了充分利用DNA的优势，在基于计算机的系统中建立一个通用的存储平台，必须能够以电子方式访问和读取信息。为了发展这种转化能力，需要一些技术和基础性的进步。本项目的目标是开发用于创建基于电可读DNA的存储系统的方法。具体而言，该提议旨在：i）优化和控制使用分子和离子掺杂剂的组合的自下而上自组装技术生长的DNA纳米线的电荷传输特性，以及无机结构的模板化生长; ii）通过检查序列、结构和长度对传输特性的影响来开发用于创建基于DNA的多级存储单元的设计规则; iii）联合收割机结合这些知识来开发基于DNA的交叉线（X-wire）只读存储器系统; iv）开发预测传输模型来模拟这种存储器结构的功能;以及v）开发计算机辅助设计（CAD）工具，其可用于对大规模存储器结构的自组装进行编程。这种方法的成功将为碳基电子、存储器技术和基于DNA的纳米组装创造转化能力，该项目的广度将导致各种领域的新知识。它将：i）增强我们对DNA固有电荷传输特性的基本理解; ii）提供关于如何化学控制这些特性以实现所需电响应的见解; iii）提供关于如何扩大DNA纳米结构的自组装的新见解; iv）帮助开发用于建模和控制基于DNA的存储器的组装和可寻址性的新CAD工具; v）提供有关如何将生物材料与传统半导体技术相结合的基础信息; vi）将DNA自组装的实用性推进到纳米级电子材料的新型制造平台; vii）实现在这些自下而上的混合系统中建模运输的新方法;以及viii）提供关于用于下一代计算的新颖存储器体系结构的信息。在这些领域开发的知识将使碳基，纳米级电子设备的设计与所需的功能从下向上。更广泛地说，该项目的成功将提供一个广泛的、系统的框架，可以遵循这个框架来开发纳米级电子材料的独特电子器件范例。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的知识价值和更广泛的影响审查标准进行评估来支持。

For decades engineers have aimed to develop a universal memory technology that was low cost, reliable, high density, and non-volatile. Ideally, this technology could be quickly written, read, or erased, and would last indefinitely in any defined state. However, current technologies have limited lifetimes, are often arduous to write, consume significant amounts of power, and are not capable of sustaining the current global data growth. Biological systems on the other hand, solved this problem billions of years ago using deoxyribonucleic acids (DNA) coupled with enzymatic methods for reading, writing, and erasing the data. In fact, the average human writes 40 exabytes of data each day while consuming comparatively little energy. Moreover, this data can be stored for hundreds or thousands of years. Thus, DNA represents a unique and interesting platform for developing memory technologies for the next generation of electronic devices. However, in order to leverage its phenomenal storage capabilities and become a viable memory technology contender, a number of important technical and fundamental hurdles must be examined and overcome. As an initial step toward this goal, this proposal aims to create a DNA-based Read-Only Memory (ROM) that can be patterned, placed, and programmed as desired, can be read electrically, and is capable of interfacing with conventional semiconductor electronics for long-term data storage and retrieval. To achieve this goal, we have established a collaborative, multidisciplinary team working at the nexus of biological systems electrical and computer engineering and charge transport physics. This Team has expertise in the control and assembly of DNA nanostructures, nano- and molecular electronic systems, and the theory and modeling of nanoscale electronic devices. Together, this team will work with students and junior researchers to understand and control the charge transport properties of DNA-based nanostructures, to assemble DNA-based memory devices and circuits, to develop tools for modeling and programming these systems, and to train a new generation of scientists and engineers capable of working at the interface between biology and nano/electrical engineering. Graduate students involved in this project, will obtain interdisciplinary training involving electrical engineering, device physics, chemistry, biochemistry, and material science. In addition, this transdisciplinary research project is also integrated with an outreach program aimed at expanding the enrollment of under-represented minorities and female students in STEM fields, providing research experience for undergraduate students, and introducing K-12 students to cutting edge science and engineering problems. To fully harness the advantages of DNA for a general memory platform within semiconductor-based systems, it must be possible to access and read information from it electronically. To develop this translational capability, several technological and fundamental advances are required. It is the goal of this project to develop methods for creating an electrically readable DNA-based memory system. Specifically, this proposal aims: i) to optimize and control the charge transport properties of DNA-nanowires grown using bottom-up self-assembly techniques using a combination of molecular and ionic dopants, and templated growth of inorganic structures; ii) to develop design rules for creating DNA-based multi-level memory cells by examining the effects of sequence, structure, and length on the transport properties; iii) to combine this knowledge to develop DNA-based cross-wire (X-wire) read-only memory systems; iv) to develop predictive transport models to simulate the functionality of this memory architecture; and v) to develop Computer-Aided Design (CAD) tools that can be used to program the self-assembly of large-scale memory architectures. The success of this approach will create translational capabilities for carbon-based electronics, memory technologies, and DNA-based nano-assemblies, and the breadth of this project will result in new knowledge in a variety of realms. It will: i) enhance our fundamental understanding of the inherent charge transport properties of DNA; ii) provide insights into how to chemically control these properties to achieve the desired electrical responses; iii) provide new insights into how to scale-up the self-assembly of DNA nanostructures; iv) aid the development of new CAD tools for modeling and controlling the assembly and addressability of DNA-based memories; v) provide foundational information about how to interface biological materials with conventional semiconductor technologies; vi) advance the utility of DNA self-assembly to a novel manufacturing platform for nanoscale electronic materials; vii) enable new methodologies for modeling transport in these bottom-up hybrid systems; and viii) provide information about novel memory architectures for next-generation computation. The knowledge developed in these areas will enable the design of carbon-based, nanoscale electronic devices with desired functionality from the bottom-up. And more generally, the success of this project will provide a broad, systematic framework that can be followed to develop unique electronic device paradigms for nanoscale electronic materials.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.