A new method to obtain reproducible measurements on single-wavelength, single-angle-of-incidence, null-seeking, polarizer-compensator-sample-analyzer ellipsometers
Abstract
A method is discussed which enables routine users of single-wavelength, single-angle-of-incidence, null-seeking polarizer-compensator-sample-analyzer ellipsometers to obtain reproducible measurement result on reasonably aligned production ellipsometers without tediously having to adjust and/or characterize them. This method is based on a numerical analysis. of data taken from a carefully prepared set of SiO2/Si samples, which determines a number of sample and null-seeking ellipsometer parameters. The method is shown to give results for ellipsometer alignment corrections equivalent to those obtained by standard, more tedious, procedures and it yields material parameters consistent with accepted values for the SiO2/Si system. Application of these results is demonstrated, including measurements on SRM-2530 standards obtained from the National Institute of Standards and Technology. We also propose that the error term, which is used in our numerical analysis to characterize the ellipsometer, should be used routinely as a gauge of the combined measurement and model errors for all samples that are measured.
- Publication:
-
Metallurgical Coatings and Thin Films
- Pub Date:
- 1991
- Bibcode:
- 1991meco.proc..381P
- Keywords:
-
- Ellipsometers;
- Error Analysis;
- Incidence;
- Least Squares Method;
- Parameterization;
- Polarizers;
- Data Processing;
- Film Thickness;
- Optical Properties;
- Silicon Oxides;
- Instrumentation and Photography