Woollam V-VASE Ellipsometer

This instrument in a Variable Angle Spectroscopic Ellipsometer (VASE) which has small spot focusing optics and an automated X-Y translation stage. This instrument is primarily used to measure the thickness and optical properties (index of refraction and extinction coefficient) of thin film materials. These measurements are made by analyzing polarized light reflected from the sample surface, and fitting the measured data to a model. Typically dielectric and semiconductor films are measured, though very thin metal films can also be analyzed.

Instrument Status

• Last updated 17:30 on 09/29/2006.
• The Ellipsometer is UP.

Instrument Capabilities

Measurement Ranges

• Wavelength Range: 190 - 2000 nm
• Hg Arc lamp and monochromator
• Tungsten-halogen lamp
• Angles: 70 to 75° typical
• Transparent films on transparent substrate
  • Use focusing optics

Data acquired

• Film thickness (~1 monolayer to > 1 µm)
  • Single layers
  • Multiple layers
  • Surface Roughness
• Index of refraction
• Extinction coefficient

Samples handling

• Designed for planar samples (wafers)
• Can hold a 4" wafer
• X-Y translation stage with 6" range
• Automated multispot data collection