SE Spectroscopic Ellipsometer System

Spectroscopic ellipsometry (SE) is a powerful technique to precisely measure thin film thickness, determine optical constants, investigate surface and interface phenomenon and many other physical, chemical and optical properties of materials. Angstrom Sun Technologies Inc designs and manufactures high quality spectroscopic ellipsometer systems with various options for different applications. Besides ellipsometer system itself, the advanced analysis software is essential to extract the desired information as above-mentioned, such as thickness, roughness, alloy concentration and dielectric constants. TFProbe™ 3.0 from us offers powerful analysis functions for ellipsometry sensitivity study, photometry / ellipsometry simulation and data regression. Unique but configurable mode allows different users to access different level and suitable for both R&D and production quality control purpose.

For questions on ellipsometry, visitor can check FAQ section at our website. If you have any questions not answered there, please feel free to contact us.

Example Model: SE200BA-M300

SE: Spectroscopic Ellipsometer

200: Indicates Wavelength range

B: Detecting Type

               A: Scanning monochromator with single element detector

               B: Array Type detector with spectrograph or interferometer

A: Variable Incident Angle Type

               A: Automatic variable angle with precision Goniometer and computer controlled (Click for Example)

               M: Manually adjustable incident angle at 5 degree interval (Click for Example)

M: Mapping Stage

300: Maximum mapping sample size

• Wavelength Extension to VUV or IR Range

• Stage Size

• Probing beam Spot size

• Photometry

• Heating/Cooling Stage

• Mapping stage in X-Y or Rho-Theta

• Combined SE and MSP functions

· Semiconductor fabrication (PR, Oxide, Nitride..)

· Liquid crystal display (ITO, PR, Cell gap…..)

· Biological films and materials

· Optical coatings, TiO₂, SiO₂, Ta₂O₅…..

· Semiconductor compounds

· Functional films in MEMS/MOEMS

· Amorphous, nano and crystalline Si

· Solar Cell Industry

· Medical device fabrication

There are many techniques for characterizing materials, each having its own advantages and disadvantages and each being uniquely able to reveal material properties that other techniques can't access. Spectroscopic ellipsometry (SE) is an optical technique that is particularly flexible in that it can be used to determine the optical and physical properties of a wide variety of thin-film materials. Its ability to do this without contact or damage to the material of interest has seen it become routinely used in R&D laboratories and within manufacturing facilities for monitoring thin film growth and deposition processes.

SE relies on the determination of the polarization state of a beam of polarized light reflected from the sample under characterization. When performing SE measurements, the polarization state is determined at many discrete wavelengths over a broad wavelength range. The change in the polarization state can be traced to the physical properties of the thin film by means of a model. Characteristics such as layer thickness, surface roughness, refractive index (n) and extinction coefficient (k) of the materials can be determined with excellent precision through regression analysis.
The instrument determines two ellipsometry angles Ψ and Δ, which describe the change in the polarization state of the beam upon reflection from the sample. The ratio of the amplitude of the polarization within the plane of incidence (P) to the amplitude of the polarization perpendicular to the plane of incidence (S) is represented by Ψ. The phase retardation between the two polarization vectors P and S is represented by Δ. Changes in Δ and Ψ essentially depend upon the optical constants, n and k, of the layer materials and substrate, physical thickness of the individual layers and surface roughness. A regression analysis allows the determination of these parameters.
SE data for Δ and Ψ are obtained at a number of incident angles in a plane normal to the sample surface and typically at 100-200 different wavelengths for each angle. SE instruments use a white light source and individual wavelengths are selected for detection by either a motor driven monochromator, or a multi-channel detector that can detect many wavelengths simultaneously. Increasing the number of angles and wavelengths at which data are acquired improves analysis precision, especially for complicated epitaxial structures.

For more information regarding ellipsometry technique, please visit out publication, presentation websites or ellipsometry database. You are also welcome to write us for any specific questions.

1. System configuration and Specifications subject to change without notice

2. * Film property, surface quality and layer stack dependent

3. Customized system available for special applications

4. TFProbe is registered trademark of Angstrom Sun Technologies Inc.