A device for measuring the complex indices of materals and thin-film thickness

An ellipsomeric analyzer comprises a polarized light source unit, a set of phase modulating units to control the phase of measuring light beam, a set of reference analytical unit for adjusting the change of intensity of the measured light beam, a set of light controlling units to control the incident angle of the test object and the direction of the incident beam, and also reflects the light beam along the original path back to the testing object after the action of the test object, and enters into a polarized analytical unit. It is noted that the light controlling unit returns the measuring beam along the original path back to the test object and then enter into the polarized analytical unit, and this mechanism that passes the measuring beam through the test object twice can increase the accuracy of the measured result of the ellipsomeric analyzer. In addition, this invention has a design of light control unit that accurately controls and changes the incident angle and direction of the measuring light breaking through the limit of a traditional ellipsomeric analyzer which is unable to easily generate an accurate incident angle for the measurement. The ellipsomeric analyzer according to the present invention has a smaller size and can be broadly applied to the on-line real-time inspection on the production line for different high technological industries such as semiconductor, optical film coating and chemical industry.