Metrological Traceability And Application Of Scanning Electron Microscopy

In the new century, the SEM conductor industry has been developing rapidly, chips and other components also gradually evolve from the previous micron to nano stage. This puts forward new requirements to measurement science. Nanometer measurement will play a positive role in the industrial development. In the measuring detection of micro-nano geometry, as a result of the existence of physical diffraction limit, there is a lot of limitations of the traditional optical microscope. Therefore, scanning electron microscopy (SEM) is especially important in nanometer measurement.In order to satisfy the requirements of conductor chip’s line width and the other micro geometry measurement,National Institute of Metrology start the development of scanning electron microscopy (SEM)standard device.The equipment takes advantage of high speed and high precision double nano displacement structure to realize rapid and accurate measurement, which improves the efficiency of the measurement. At the same time, interferometer measurement system is used to realize the traceability of measurement results. In this paper, we study the traceability principle of modified measurement type scanning electron microscope (SEM), and evaluate measurement uncertainty of the device. We also measure the geometry of micro-nano using the device, and obtain the effective diameter of micro-nano structure.The paper introduces measurement type scanning electron microscope (SEM) system, including the basic construction of measurement type scanning electron microscopy (SEM), traceability principle, the uncertainty analysis caused by main error sources and application of micro nano particles, etc. The main works are as follows:Firstly, the background and significance of measurement type scanning electron microscopy (SEM) are introduced, including nanometer measurement technology, EUVL, the main methods and equipment of line width measurement. We analysis the advantages and disadvantages of the measurement type scanning electron microscope, and the research status of domestic and overseas. The system structure and the main structure design of measurement type scanning electron microscopy (SEM) modified based on the ZEISS ULTRA 55 scanning electron microscope (SEM) are analyzed.We summarize and describes the measurement type interferometer measurement system of scanning electron microscopy (SEM),which can be traced back. The design of measurement type double displacement of scanning electron microscopy (SEM) are introduced. We select a wide range of mechanical displacement to obtain a wide range of movement, and we select Nanoscale displacement of piezoelectric ceramic to obtain small scale accurate positioning. Then, we introduce the laser interferometer measurement system. It is the key to the device to realize the traceability. Finally, this paper expounds the function module of the control system and shows the scanning electron microscopy (SEM) images of two-dimensional grid.Next, the class A evaluation and class B evaluation to the uncertainty of measurement are discussed. We analysis and evaluate the uncertainty in measurement type scanning electron microscopy (SEM).Mainly from the following several aspects: 1)The error of the measurement system;2)geometric error;3)Electron beam spot drift;4)The uncertainty of image pixels;5)Mechanical vibration and displacement of nanometer vibration;6)repeatability of measurement;7)The effects of temperature changes. Finally, we put the synthetic measurement uncertainty of measurement type scanning electron microscopy (SEM).Then, the application field of measurement type scanning electron microscopy (SEM) are introduced.The main application is in measurement test image analysis and processing filed, defect detecting, the three-dimensional structure observation, SEM conductor, electronic industry, etc. We analyze the scanning electron microscopy (SEM) in detail in the application of the nanometer particle size measurement. Silica particles, for example, by setting appropriate parameters of SEM, using scanning electron microscopy (SEM) photographs of silica particles, After image processing. To calculate the effective diameter of nano silicon dioxide particles of the application process, measurement type scanning electron microscopy (SEM) plays a important role in the field of micro-nano measuring.Finally,we summarize the work, and discuss the improvement work measurement type of scanning electron microscopy (SEM) in the future.