MRI: Acquisition of a 3-D Nanolithography System

三维（3D）打印在快速成型和按需制造零件方面掀起了一场革命。该技术可以按需制造传统方法无法制造的复杂结构。目前的3D打印系统范围从业余爱好者的桌面系统到工业原型和制造系统。由于材料、喷嘴或定位硬件精度的限制，大多数仪器的最小特征尺寸限制在约100微米。该项目将获得一个先进的3D纳米光刻系统，该系统利用近红外脉冲激光的双光子聚合光刻技术。有了这个系统，可以将3D打印扩展到纳米级，允许在立方厘米体积上实现亚微米级的3D特征尺寸。按需纳米制造能力的可用性将扩大研究小组对其他不熟悉这种技术的学科的参与。例如，该仪器将支持岩石物理在能源提取、食品工业生物污染预防、脑机接口、小型医疗设备和嵌入式生理传感器等方面的工作。此外，该项目将在犹他大学和盐湖城社区学院创建课程模块，以利用拟议的仪器。作为该项目的一部分，一个由博士生组成的“专家用户团”将接受系统培训，这种体验远远超出了典型的项目。计划在项目的第二年举行会议，以便用户在这个不断增长的用户社区中分享经验教训、最佳实践和新技术。3D纳米光刻系统将支持许多正在进行和提议的跨学科合作研究方向。例如，该系统将在多个应用领域中对固体/流体界面特性的理解发挥基础作用，包括用于能量存储/提取的数字岩石物理、优化食品工业中使用的超滤膜、微生物运动研究和微血管结构研究。这些都是复杂的问题，所有这些问题都涉及到整合最先进的自然样品显微成像，基于物理的建模，以及创建具有不同物理和化学异质性水平的分层合成纳米结构材料，以验证多尺度模型，然后用于应用程序开发。3D纳米光刻系统是创建这些合成材料模型的理想工具，可以进行详细的实验表征。在神经接口领域，3D纳米光刻工具将促进大脑和周围神经的新光学和电子接口的创建，充分利用高度灵活的3D模式功能，根据植入位置和急性或慢性应用定制这些接口。该工具将能够开发许多其他嵌入式生物医学设备，包括用于自我调节起搏器的微型支架，以及基于新型光响应聚合物材料开发的用于连续生理监测的小型化传感器。其他影响领域包括用于生物分析系统的纳米流体装置，基于激光的金属3D打印，纳米级近场静电纺丝，纳米级复合材料以及用于有源太赫兹频率设备的新型二维（2D）材料。该奖项反映了美国国家科学基金会的法定使命，并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，被认为值得支持。

Three-dimensional (3D) printing has created a revolution in rapid-prototyping and on-demand creation of parts. This technology can enable on-demand manufacturing of complex structures that could not be built using conventional methods. Current 3D printing systems range from hobbyist desktop systems to industrial prototyping and manufacturing systems. Most instruments are limited to minimum feature sizes of about 100 microns due to limitations in materials, nozzles, or accuracy in positioning hardware. This project will acquire an advanced 3D nanolithography system that utilizes two-photon polymerization lithography from a near-infrared pulsed laser. With this system, it is possible to extend 3D printing to the nanoscale, allowing for sub-micron 3D feature size across cubic-centimeter volumes. The availability of on-demand nano-manufacturing capability will broaden the participation of research groups to other disciplines not familiar with this type of technology. For example, the proposed instrument will support efforts in rock physics for energy extraction, prevention of bio-fouling in the food industry, brain-machine interfaces, miniaturized medical devices, and embedded physiological sensors. In addition, this project will create coursework modules at both University of Utah and Salt Lake Community College to utilize the proposed instrument. As part of this project, an "expert user corps" of Ph.D. students will be trained on the system, an experience that goes well-beyond that of a typical program. A meeting is planned during the second year of the project for users to share lessons learned, best practices, and new techniques in this growing user community. The 3D nanolithography system will support a number of on-going and proposed cross-disciplinary collaborative research directions. For example, the system will play a fundamental role in the understanding of solid/fluid interfacial properties across multiple application areas, including digital rock physics for energy storage/extraction, optimizing ultrafiltration membranes used in the food industry, study of micro-organism locomotion, and study of microvascular structures. These are complex problems, all of which involve the integration of state-of-the-art microscopic imaging of natural samples, physics-based modeling, and creation of hierarchical synthetic nanostructured materials of various levels of physical and chemical heterogeneities to validate multiscale models that are then used in application development. The 3D nanolithography system is the ideal tool to create these synthetic material models with which detailed experimental characterization can be performed. In the neural interfaces area, the 3D nanolithography tool will facilitate the creation of new optical and electrical interfaces to the brain and peripheral nerves, taking full advantage of highly-flexible 3D patterning capabilities to customize these interfaces to the implant locations and for acute or chronic applications. The tool will enable the development of a number of other embedded biomedical devices, including micro-scaffolds for self-regulated pacemakers, and miniaturized sensors for continuous physiological monitoring based upon development of new photo-responsive polymer materials. Additional impact areas include nanofluidic devices for bioanalytical systems, laser-based 3D printing of metals, nanoscale near-field electrospinning, nanoscale composite materials, and novel two-dimensional (2D) materials for active terahertz-frequency devices.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.