Collaborative Research: Understanding the Formation and Separation of Nanoscale Contacts

随着电子设备的尺寸缩小到纳米级，需要新的技术来制造和表征它们。这些新方法中的许多依赖于纳米尺寸的触针选择性地与表面接触，然后修改或测量接触区域。这些技术的功能、可靠性和精度取决于触点的特性，特别是附着力、接触面积和底层材料的变形。该奖项支持基础研究，以了解在这些长度尺度上控制触点形成和分离的物理，化学和材料科学。对纳米接触的新见解将指导现有技术的优化和新方法的开发，有助于使美国保持在先进制造和技术的最前沿。这项调查由一个跨学科的研究小组进行，并纳入了具体的方案，包括代表性不足的群体的人的参与。纳米接触行为将调查化学和结构不同的材料，与科学和技术的相关性。纳米接触实验将进行原位透射电子显微镜，将提供纳米牛顿力分辨率和埃级结构信息。这些实验将通过相同纳米接触的分子动力学模拟来补充，这些纳米接触提供了有关材料内和接触周边内发生的现象的原子级细节，这些现象在实验中无法直接观察到。这些技术将用于表征各种触点的粘附力、负载下的变形和负载相关的接触面积。总之，这些数据将能够评估描述纳米级接触的竞争假设。这些见解将对基于探针的纳米制造和基于探针的显微镜产生直接影响，这两者都需要精确理解和控制尖端/样品接触。更一般地说，在这个程序中的原位纳米级测试将产生相关的大规模应用，其中材料之间的界面包括许多纳米级粗糙接触的见解。

As the size of electronic devices shrinks to the nanometer scale, new technologies are required to manufacture and characterize them. Many of these new approaches rely on a nano-sized stylus selectively making contact with a surface, and then modifying or measuring the contacted region. The function, reliability, and precision of these techniques are determined by the properties of the contact, especially the adhesion force, the area of contact, and the deformation of the underlying material. This award supports fundamental research to understand the physics, chemistry, and materials science that govern the formation and separation of contacts at these length scales. The new insights into nanoscale contacts will guide the optimization of existing techniques and the development of novel approaches, helping to keep the U.S. at the forefront of advanced manufacturing and technology. The investigation is being conducted by an interdisciplinary team of researchers, and incorporates specific programs to include participation by people from underrepresented groups. Nanocontact behavior will be investigated for chemically and structurally diverse materials, with scientific and technological relevance. Nanocontact experiments will be conducted with in situ transmission electron microscopy that will provide nanonewton force resolution and Angstrom-scale structural information. The experiments will be complemented by molecular dynamics simulations of the same nanocontacts that provide atomic-scale detail about phenomena occurring within the materials and inside the perimeter of the contact, which cannot be viewed directly in experiment. These techniques will be used to characterize adhesion, deformation under load, and load-dependent contact area for a variety of contacts. Taken together, the data will enable evaluation of competing hypotheses that describe nanoscale contact. These insights will have direct impact on probe-based nanomanufacturing and on probe-based microscopy, both of which require precise understanding and control of the tip/sample contact. More generally, the in situ nanoscale testing in this program will yield insights that are relevant to larger-scale applications in which interfaces between materials consist of many nanoscale asperity contacts.