Smart nano-machining and measurement system with semiconductive diamond AFM probe

研制了一套高性能的金刚石原子力显微镜探针系统，该探针系统具有（1）纳米尺度超精密加工和（2）加工前后的原位形貌检测功能.器件微细加工技术的发展采用一种新的CVD工艺，利用选择性淀积技术，结合模具技术，在悬臂梁端部制作了一个金字塔形的针尖，成功地制备了厚度为5 μm的金刚石悬臂梁。实验结果表明，所制备的金刚石原子力显微镜探针具有高耐磨性的AFM测量功能。在室温下溅射锆钛酸铅（PZT）薄膜，然后在氮气气氛中以大于10℃/s的升温速率和大于500℃的温度进行快速热退火。在金刚石薄膜衬底上制备的PZT薄膜具有钙钛矿结构，极化处理后的压电常数约为65 pC/N。利用SF_6等离子体反应离子刻蚀技术成功地对PZT薄膜进行了图形化，并且没有对金刚石层造成任何损伤.基于压电传感器和驱动器的金刚石原子力显微镜探针的研制为了计算位移和驱动力，我们发展了一种基于压电层悬臂梁自由振动的理论模拟方法。根据计算结果确定了金刚石原子力显微镜探针的尺寸，并在一系列加工工艺下实现了探针。该探针的灵敏度为0.2nm，驱动力为80 μN。

We developed a high performance diamond AFM probe system with functions of (l) nano scale ultraprecision machining and (2) in situ topography inspection before and after machining.1. Development of microfabrication technology for device realizationA novel CVD process for fabrication of a diamond cantilever of 5 μm thickness was developed using a newly developed selective deposition technique together with a mold technique for fabrication of a pyramidal tip on the end of the cantilever. The fabricated diamond AFM prove was proved to have an AFM measurement function with high wear resistant properties. Lead zirconate titanate (PZT) thin film was sputtered at a room temperature, followed by rapid thermal annealing at a temperature ramp rate of more than 10℃/s and at temperatures of more than 500℃ in a nitrogen ambient. The PZT thin film fabricated on diamond thin film substrates had perovskite structure and its piezoelectric constant was about 65 pC/N after a poling treatment. The PZT thin film was successfully patterned by reactive ion etching in SF_6 plasma without any damage on a diamond layer.2. Development of diamond AFM probe with piezoelectric sensor and actuatorIn order to calculate displacement and actuation force, we developed a theoretical simulation method based on free vibration of a cantilever with a piezoelectric layer. A diamond AFM probe, whose dimensions were determined by calculated results, was realized under a sequence of fabrication processes. Properties of the probe were estimated to have a sensing resolution of 0.2 nm and an actuation force of 80 μN.