STTR Phase I: Direct 3D Fabrication Platform for Single-Crystal Silicon and Silicon Carbide

这个小型企业技术转移（STTR）第一阶段项目的更广泛影响是3D制造技术的发展，该技术为高质量的单晶硅和碳化硅提供了3D打印的好处（即快速原型制作，复杂3D结构的创建等）。该技术将与传统的基于光刻技术的半导体制造竞争，如手机和汽车安全气囊中的加速度计等微机电系统（MEMS）传感器，光通信网络和数据中心中使用的硅光子学，用于药物发现和其他生物医学应用的微流体，以及用于集成电路3D集成的中间体。3D制造技术在三个方面优于传统半导体制造：1)将原型制造时间缩短了100倍，从而节省了成本并提高了研发周期的速度；2)用一种工具取代多种制造工具，显著降低资本支出；3)直接创建复杂的3D结构，显着改善了基于光刻的制造有限的挤压2D几何形状。此外，3D制造能力可以扩展到宏观部件和影响行业，如能源转换和航空航天，提供由单晶硅碳化硅制成的复杂3D结构，用于极端高温操作。该项目将先进的非线性光学元件与半导体材料的电化学蚀刻相结合，以实现单晶硅和碳化硅的3D制造技术。虽然在这个项目的前期工作中已经证明了基本的物理机制，但关于材料去除过程的控制、最终结构的表面质量以及材料可以去除的速度，仍然存在一些重要的问题。这些问题需要解决，以了解哪些应用的3D制造技术是商业上可行的。本项目的技术目标和任务旨在通过仔细的实验来回答这些问题，并根据所获得的数据确定最有希望的应用。将对硅和碳化硅进行实验，探索3D制造过程中输入参数和变量的一系列排列。这些实验的结果将被研究和表征，以确定最佳的蚀刻参数和这些蚀刻参数可能的蚀刻结果。在第一阶段STTR项目结束时，3D制造技术的能力将得到更好的理解，并将确定商业化能力的明确路径。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。

The broader impact of this Small Business Technology Transfer (STTR) Phase I project is the development of a 3D fabrication technology that provides the benefits of 3D printing (i.e., rapid prototyping, the creation of complex 3D structures, etc.) for high-quality, single-crystal silicon and silicon carbide. The technique will compete with traditional photolithography-based semiconductor manufacturing for applications such as MicroElectroMechanical System (MEMS) sensors such as accelerometers in cell phones and vehicle airbags, silicon photonics used in optical communications networks and data centers, microfluidics for drug-discovery and other biomedical applications, and interposers for 3D integration of integrated circuits. The 3D fabrication technique is superior to traditional semiconductor fabrication in three ways: 1) Up to a 100X reduction in prototype manufacturing time, resulting in cost savings and increasing the speed of R&D cycles; 2) Significantly reducing CapEx by replacing multiple fabrication tools with one single tool; and 3) Creating complex 3D structures directly, significantly improving on the limited extruded 2D geometries available from photolithography-based fabrication. Additionally, the 3D manufacturing capability can be extended to macro-scale components and impact industries such as energy conversion and aerospace by providing complex 3D structures made from single-crystal silicon carbide for extreme high-temperature operation.The proposed project combines elements of advanced nonlinear optics with electrochemical etching of semiconductor materials to enable the 3D manufacturing technique for single-crystal silicon and silicon carbide. While the fundamental physical mechanism has been demonstrated in work leading up to this project, there are important questions remaining about control of the material removal process, the surface quality of the final structure, and the rate at which material can be removed. These questions need to be addressed to understand which applications of the 3D manufacturing technique are commercially viable. The technical objectives and tasks for this project have been designed to answer these questions through careful experimentation and, with the data obtained, identify the most promising applications to pursue. Experiments for both silicon and silicon carbide will be conducted that explore a range of permutations of input parameters and variables for the 3D manufacturing process. Results of these experiments will be studied and characterized to identify optimal etch parameters and the etch results possible with those etch parameters. At the conclusion of this Phase 1 STTR project, the capabilities of the 3D fabrication technique will be better understood and a clear path for commercializing the capability will be identified.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.