SBIR Phase II: Batch Wafer-Scale Fabrication of Improved Probe Tips for Scanned Probe Microscopy

这个小型企业创新研究(SBIR)第二阶段项目将完善用于制造超硬和超硬原子力显微镜(AFM)尖端的专有批量处理技术。新的流程包括两个步骤。首先，化学气相沉积(CVD)被用来在尖端涂上一种化学惰性、高导电性和极硬的材料。其次，我们开发的一种专利工艺，场定向溅射锐化(FDSS)，将探头尖端锐化到原子尺寸(尖端的曲率半径为1-4 nm)。坚硬、锋利的尖端具有相当大的科学和市场兴趣，因为尖端的几何形状和机械性能对AFM测量结果有很大影响。目前的项目将进行研究，以完善一次能够制造数百个尖端的批量晶片规模工艺。为了将该技术推向市场，将执行以下研究和开发任务：(A)优化工艺条件以重复锐化在4英寸晶片上制造的AFM探头阵列，(B)调查用各种硬膜材料覆盖和锐化AFM探头的能力，以及(C)评估用于市场驱动的探头显微镜应用的批量制造的探头尖端的性能。该项目的更广泛的/商业影响来自开发更耐磨的、可重复的和耐用的尖端(由于高硬度)并且具有AFM成像的有利特性(小曲率半径，可控制的纵横比和导电性)。该项目将使使用扫描探针显微镜成像的学术界和工业界受益。虽然原子力显微镜和相关的探针显微镜与电子显微镜相比有许多优点(例如，它们可以在环境条件下使用，并且它们可以很容易地与光学光谱学对接)，但一个显著的缺点是，由于在使用过程中磨损，探针尖端的寿命有限。超薄、非常硬、导电和相对便宜的探头尖端的开发和商业引入将显著提高AFM和相关技术的能力，例如扫描电容显微镜(SCM)，扫描电容显微镜(SCM)是微电子行业非常感兴趣的一种技术，因为它对集成电路的延迟故障的在线测试有用。这项研究也将有利于那些成像聚合物和其他软材料等绝缘表面的人，以及那些开发用于光刻和纳米制造应用的多针尖探针阵列的人。

This Small Business Innovation Research (SBIR) Phase II project will perfect a proprietary batch-scale processing technique for fabricating ultrahard and ultrasharp atomic force microscopy (AFM) tips. The new process involves two steps. First, chemical vapor deposition (CVD) is used to coat the tips with a chemically inert, highly conductive, and extremely hard material. Second, a patented process that we have developed, field directed sputter sharpening (FDSS), sharpens the probe tip to atomic dimensions (1- 4 nm radius of curvature at the tip apex). Hard, sharp tips are of considerable scientific and market interest because tip geometry and mechanical properties significantly impact the results of AFM measurements. The current project will carry out research to perfect a batch wafer-scale process able to manufacture hundreds of tips at once. In order to bring the technique to market, the following research and development tasks will be carried out: (a) optimization of process conditions to reproducibly sharpen arrays of AFM probes fabricated on 4-inch wafers, (b) investigation of the ability to coat and sharpen AFM probes with a variety of hard film materials, and (c) assessment of the performance of batch-fabricated probe tips for market-driven probe microscopy applications.The broader/commercial impact of the project arises from the development of robust, reproducible, and durable tips that are more resistant to wear (due to the high hardness) and have favorable characteristics for AFM imaging (small radius of curvature, controlled aspect ratio, and electrically conductive). The project will benefit the academic and industrial communities who use scanning probe microscopy imaging. Although AFM and related probe microscopies have many advantages over electron microscopy (e.g., they can be used under ambient conditions and they can be easily interfaced with optical spectroscopy), one significant drawback is that the probe tips have limited lifetimes owing to wear during use. The development and commercial introduction of probe tips that are ultrasharp, very hard, conductive, and relatively inexpensive will significantly enhance the capabilities of AFM and related techniques such as scanning capacitance microscopy (SCM), a technique of great interest to the microelectronics industry because it is useful for the on-board testing of integrated circuits for delay faults. The research will also be of benefit to those who image insulating surfaces such as polymers and other soft materials where static charge build-up limits efficacy, and to those developing multi-tip probe arrays for lithographic and nanomanufacturing applications.