System parameter calibration method for imaging ellipsometer

Abstract

The invention discloses a system parameter calibration method for an imaging ellipsometer. The system parameters of the imaging ellipsometer can be calibrated and comprise the polarization direction of a polarizer, the polarization direction of a polarization analyzer and the original point points of left and right grating rulers. The calibration method is simple and accurate in process and high in repeatability. After the calibration is finished, the system part does not need to be adjusted, and direct measurement can be realized, so that the measurement process is simplified, and the measurement accuracy is improved.

Description

technical field [0001] The invention relates to the technical field of optical measuring instruments, in particular to a method for calibrating system parameters of an imaging ellipsometer. Background technique [0002] In the history of science, every progress in measurement technology can promote the development of science. As an important technology for studying material surface science, its measurement process has many advantages such as non-destructive, non-contact and high measurement accuracy for samples. It is used in more and more fields such as optical industry, electronic industry, biochemistry, and metal materials. achieved a wide range of applications. [0003] figure 1 Shown is the system schematic diagram of imaging ellipsometer, the imaging ellipsometer consists of laser, 1 / 4 wave plate, collimator, polarizer, compensator, rotating stage, analyzer, bi-telecentric lens, CCD camera , sample stage, controller, computer, left grating ruler, right grating ruler...

AI Technical Summary

Problems solved by technology

[0008] (2) To set an accurate angle of incidence, it is necessary to determine the origin position of the grating ruler on the incident arm. In practice, the origin of the grating ruler commonly used is manually calibrated, and then the external conditions are used to find the origin position, which gives the azimuth calibration process increased difficulty;

[0009] (3) In actual operation, stepper motor pulse technology is used to set the incident angle and reflection angle, so there will be problems of motor out of step or inertial overshoot, which will affect the accuracy of incident angle and reflection angle, and then affect the polarizer and detector. Determination of the azimuth angle of the polarizer

[0010] The invention with application number 201010137774 discloses a device for automatic detection of incident angle in ellipsometry system, which realizes automatic detection of incident angle, but the device needs to install position detection devices in multiple places in the system, which makes The structure of the device is complex, and the calibration of the position detection device itself is a relatively complicated process, which limits the application of the automatic detection device in the calibration of the parameters of the ellipsometer system

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