Study Of Dural-probe Three-Dimensional Surface Profile Measuring System

In the developing process of science and technology, the surface topography and profile measurement technology have becoming an important object in measuring research. The technology of surface measurement has also become one important branch of the measurement technology. Surface measurement technology is applied in lots of scientific fields, such as polymer materials science, Nano-electronics, MEMS (Micro-Electromechanical System) technology, thin film science and bioscience. It is also becoming a practical applied technology in industrial field, such as precision manufacturing field, advance material manufacturing field, microarray testing, product quality assessment field and so on. Especially in recent years, based on the development of microelectronic techniques, computing techniques, optical techniques, sensor technology and information processing technology, various sorts of surface profile and topography measuring instruments appear one after another. The measuring range is from sub-nanometer level to centimeter. All these scientific instruments have provided advanced methods for observation and analysis.In the practical measuring research, the Atomic Force Microscopy (AFM) technology performs well in atomic-level 3D surface topography measurement, for its high axial resolution. However, AFM has some weakness for its fragile probe, small range and slow speed. Another method, electro-optical distance measuring probe based on Position Sensitive Detector (PSD) is excellent in large range surface profile measurement. However, its limited resolution results in lost of surface detailed information.The issue of this project is produced in the background. A new 3D profile measuring method which combines the AFM probe with the PSD range probe is advanced, and this method can obtain both the large size 3D profile and micro morphological character of a point on the sample.Mainly research includes theoretical method, system design and establishment, and measuring experiment. The innovations and research work are as listed below: A new 3D profile measuring method which combines the AFM probe with the PSD range probe is first proposed. By this new method, the surface topography and product profile can be measured in the same stage with high efficiency.In the technical research, the dual-probe 3D surface profile measuring system was constructed. The operation mode of the two probes and two-dimensional scanning stage are designed; the data acquisition solution and logical scanning method are developed, which can achieve optimization both in time and cost.According to the specialty of the measurement, the system software are developed, which has the function of controlling scanning process, image acquisition and processing, 3D display and reconstruction.In the end, some experiments to prove the feasibility and stability of the system are completed. The experiments include the range calibration experiment of the AFM probe, the profile measuring experiment by PSD probe scanning method, and the comprehensive measuring experiments with both probes. The 3D surface profile images in local morphology and entire profile of hexagon nut, chips and annular gasket are given. The result indicates the feasibility and stability of the system.