Ultra-precise Coordinate Metrology of Three-dimensional Objects at Micrometer and Nanometer Scales

该奖项的目标是研究和开发使能技术，以实现微米和纳米尺度的三维物体的超精密坐标计量。然后，这些使能技术将用于实现三轴探测系统，该系统能够测量物体的底切和自由形状，其表面形状的关键尺寸被缩小到100 nm以下。该方法由四个阶段组成。首先，提出了一种主动三轴可重定向测头系统的设计和原型设计方法，以实现两个显著的特点：(1)主动控制探头的方位和探头尖端在扫描平面上的位置；(2)主动控制针尖-样品在两个轴上的作用力。其次，提出了针尖运动控制和稳定性分析，以实现对几何形状未知、几何变化较大的亚100 nm三维物体的稳定扫描。第三，为了同时实现超精密和高通量的坐标测量，提出了驱动增益的实时校准和热漂移的补偿，以显著降低系统时变的影响。第四，提出了两轴测力和力控制方案，以实现扫描平面内针尖-样品相互作用的精确控制，这些技术将能够同时精确控制两轴偏转和两轴针尖-样品相互作用力，这对于使用所提出的探测系统探测垂直和可再入特征是非常重要的。如果成功，由该奖项创造的使能技术将为实现主动五轴探测系统奠定基础，并将导致微米和纳米尺度的三维坐标计量的变革性变化。具体地说，该探测系统不仅将对微米和纳米尺度的坐标计量产生重大影响，而且将对包括生物、化学、医学和物理在内的广泛领域的先进仪器产生重大影响。

The objective of this award is to investigate and develop enabling technologies for achieving ultra-precise coordinate metrology of 3-dimensional objects at micrometer and nanometer scales. These enabling technologies will then be used to realize a three-axis probing system capable of measuring undercuts and free-forms of objects whose critical dimensions of surface form are scaled down to sub-100nm. The approach consists of four phases. First, a systematic approach to the design and prototyping of active three-axis reorientable probing systems is proposed to achieve two distinguishing features: (i) the orientation of the probe and the position of the probe tip in the scanning plane are actively controlled, and (ii) the tip-sample interaction forces in two axes are actively controlled. Second, tip motion control and stability analyses are proposed to enable stable scanning of sub-100nm three-dimensional objects having unknown geometry and large geometric variation. Third, real-time calibration of actuation gain and compensation of thermal drift are proposed to significantly reduce the effect of the system's time variance for simultaneously achieving ultra-precise and high-throughput coordinate metrology. Fourth, two-axis force sensing and force control schemes are proposed to enable precise control of the tip-sample interaction in the scanning plane.These technologies will enable precise control of 2-axis deflection and of 2-axis tip-sample interaction force simultaneously, both of which are very important for probing vertical and re-entrant features using the proposed probing system. If successful, the enabling technologies created from this award will lay the foundation for realizing active 5-axis probing systems and will lead to transformational changes in three-dimensional coordinate metrology at micrometer and nanometer scales. Specifically, the probing system will not only have significant impact on coordinate metrology at micrometer and nanometer scales, but also on advanced instrumentation in a wide range of fields including biology, chemistry, medicine, and physics.