双光路扫描式微型机构三维测量系统

【作者】 单小磊；

【导师】 张冬仙； 章海军；

【作者基本信息】 浙江大学 ， 光学工程， 2008， 硕士

【摘要】 科学及其技术的不断进步使得微型化逐渐成为近代工业发展的趋势。随着微细加工技术特别是微机电(MEMS)系统的不断发展,微型机构已经越来越多的出现在机械工业,生物医学,航天航海等各个领域。微型机构的三维形貌对物体的导电性,导热性,反射性,抗腐蚀性以及其他方面的性能都有很大的影响。近些年,随着计算机技术、光学和光电子技术的迅速发展所带来的测量技术的不断更新,对于MEMS这类的微型机构三维形貌和结构的测量越来越受到人们的关注。传统的物体三维测量技术有飞行时间法、光触针法、干涉测量法、原子力显微镜法。但是这些测量方法只能对物体的表面一部分进行简单的形貌或粗糙度进行测量。而不能对MEMS这类微型机构整体的三维结构和各个部分的厚度进行综合性的反映。因此,目前非常需要发展一种能够准确、直观的反映微型机构三维结构和精确标度微型机构各个部分厚度的三维测量技术。本文的研究课题就是在上述的背景上,提出了一种双光路扫描式微型机构三维测量系统。该系统实现了非接触、无损、在线实时测量。其纵向分辨率达到2微米,测量范围从几十微米到几厘米。该系统不仅可以直观的反映出微型机构的三维概貌,还能够精确的测出微型机构的各个部分的厚度。为微型机构的性能的研究提供了一种重要的依据。本论文分别从理论方法、系统设计以及实验测试三个方面对这种三维测量系统进行了研究,主要创新点和研究工作总结如下:首次提出了双光路扫描式微型机构三维测量的新方法。并对这种方法进行了可行性的理论分析。这种方法不仅能够快速准确的测量出微型机构的三维结构而且可以测量微机机构各个部分的厚度。可以作为研究MEMS这类微型机构三维结构和性能的重要工具。研制开发了一套双光路扫描式微型机构三维测量系统。设计了双光路的光电检测探头。可以调节激光器的位置和光束的角度,保证测量的准确度。搭建了二维扫描台,可以对样品进行精确的定位和扫描。设计出光电检测信号的处理电路和步进电机的控制电路。设计出了完整的软件系统,率先实现了利用各点的厚度信息重建出微型机构的三维结构。软件系统中包括扫描台的扫描控制、微型机构三维信息数据采集与运算、微型机构的三维结构重建等等。利用自制的双光路扫描式微型机构三维测量系统进行了微型机构的三维结构测量实验,首次实现了在直观测定微型机构三维结构的同时精确测得各部分厚度数据。实验内容包括标样测量实验,一维的台阶结构、凹型结构的扫描测量,较大范围的垫片、电容、指针结构扫描实验和简单的小尺寸的微型机构的扫描实验。得出了较好的实验结果,验证了系统的稳定性与精确度。更多还原

【Abstract】 During the developing process of the science and technology, miniaturization is becomes a trend in modern industry. With the development of processing technology of micro device, especially the MEMS (Micro-Electromechanical System) technology, micro organization is applied in a lot of areas, such as machinery industry area, biological medicine area, aerospace and navigation area etc. The three-dimensional shape of micro organization has great effect to the conductivity, thermal conductivity, reflection, anti-corrosion property and other performances of the micro organization. So in recent years, with the development of computer technology, optical technology and optoelectronic technology, measuring the three three-dimensional and three-structure of micro organization, such as MEMS, is attracting more and more attention.There are plenty of traditional technologies for three-dimensional measurement, for example, time-of-flight method, optical stylus method, atomic force microscopy (AFM) method. However, such traditional methods can only measure a part of simple shape of the object’s surface or its surface roughness. They can not reflect the 3D structure and the thickness of every part of the micro organization. So it is necessary to develop a new measuring technology to reflect the 3D structure of the micro organization and mark the thickness of every part of it accurately.The issue of this project is produced in the background. We produce a 3D measurement system of micro organization based on two-ray-path scanning. The system can realize the measurement of non-contact, non-destructive in-situ and real-time. The vertical resolution is 2μm. The lateral resolution is 20μm. And the scanning range can reach from tens of microns to tens of millimeters. The system can not only reflect the 3D structure of the micro organization, but also can get the accurate thickness of its every part. The measure result provides an important basis for the performance study of micro organization.In this project, I have worked on theoretical method, system design and establishment and measurement experiment. The innovations and research work as follows:Theoretically, it brings forward a new method of micro organization 3D measurement based on two-ray-path scanning and does the feasibility analysis. The system can reflect the 3D structure of the micro organization and mark the thickness of every part of it.In the technical research work, we construct the 3D measurement system of micro organization based on two-ray-path scanning. The two-ray-path probe we designed for photoelectric detection can adjust the position and angle of the beam to ensure the accuracy of the measurement. The two-dimensional scanning stage can ensure the precisely locate and scanning accurately. We design the circuit processing the photoelectric detection signal and the circuit for controlling the stepping motor. The system software is compiled, including scanning control, data acquisition and computing and 3D reconstruction.In the end, we have done some experiments to prove the stability and accuracy of the system. The experiments include the calibration experiment, one-dimensional step structure experiment, one-dimensional concave structure experiment, gasket structure scanning experiment, capacitance structure scanning experiment, pointer structure scanning experiment and simple micro organization structure scanning experiment.更多还原