Research On Automatic Measuring Device Of Reflective Model Contour

With the development of science and technology,and also the improvement of production process,Accuracy of measurement which application to integrated circuit industry,sophisticated manufacturing,instrument and meter industry need to be improved,for this reason measuring the parameters of geometric characteristics of has become a significance.The price of measurement of microcosmic critical dimension is expensive,slow detection speed,it requires a higher environmental condition of measurement,and has a complicated installation process.Therefore,it is proposed automatic measuring device of reflective contour model contour.This device combines laser self-focusing technique and CCD micro vision image processing technique to solve the question that extracts edge detection scheme of critical dimensions.The main contents of this paper include the following aspects:(1)In order to get the measurement accuracy and repeatability of the experiment platform which has been set up,using the step gauge to measure the experimental instrument accuracy and get the result.Getting calibration of the standard step difference of the step gauge which processing the data of the signal of edge extraction from experiment instrument,comparing with the standard value of step gauge to get difference.At the same time to repeat scanning of the surface position information of step gauge and obtain the location information of each point to verify instrument repeatability.(2)After setting the port check information,the displacement experiment platform uses a serial port communication connected to a computer.The system can realize absolute displacement and relative displacement movement,and it also has timing control function and equidistant movement function.Due to the requirement the device need high accuracy.Grating is manual installation and for this reason which will bring the error which the grating has a distortion,it also gets error feedback of position,the system must be through the compensation to meet precision requirement.The compensation work through getting difference of each anchor point which detected by laser interferometer,after completing compensation work the displacement gets the accuracy requirements.(3)The system based on technical support which use laser self-focusing sensor and CCD vision sensor for software interface design,and uses serial port communication technology to connect and command laser self-focusing sensor,and it also realized the function of real time read about height information of each location,combines the position information which got from grating of two-axis displacement with the microcosmic critical dimension got from image which uses sub-pixel edge extraction processing technology,the edge micro critical dimensions were obtained accurately,completed calibration micro geometric structure work.