System Description
Ellipsometry is a method for determining the refractive index and extinction coefficients of a sample by measuring the change in polarization state of surface reflected light. Film thickness and optical constants of an adsorption layer or oxide film on a substrate surface can be determined with exceptional sensitivity.
Conventional interference spectroscopy utilizes light passed through separate optical paths, while ellipsometry is a form of interferometry that uses two vibrational components with the same optical path, providing measurements with excellent accuracy and sensitivity.
The PEM dual lock-in system of JASCO's ellipsometer provides a stable measurement with additional capabilities including high-speed data sampling and wavelength scanning.
System Features
Automated wavelength scanning
The PEM dual lock-in system (JP Pat. # 2064627) automatically controls
the PEM drive voltage for the current wavelength with an optical servo
(JP Pat. #2081599) to increase ordinate accuracy during high speed
scanning.
High-speed data sampling
Using high-speed electrical modulation, the PEM dual lock-in system
enables high-speed data sampling in as little as 1 millisecond (optional 20
microseconds), far faster than systems that mechanically rotate a
polarizer/analyzer combination.
High stability and reliability
The PEM dual lock-in system offers a static measurement free from
mechanical error with high stability by using the optical servo and an
optical reference.
Highly sensitive thin film analysis
The PEM dual lock-in system employs a proprietary polarizing
configuration offering maximum sensitivity for extremely thin dielectric
and semiconductor films.