ON  THE  NEW  POTENTIALS  OF  ELLIPSOMETRY  ARISING 
FROM  THE  NULL  OPTICAL  CIRCUIT.
ELLIPSOMETRY  OF  REAL  SURFACE  STRUCTURES.
3. METHODS  FOR  PRECISION  DETERMINATION  OF  ELLIPSOMETER  PHASE  COMPENSATOR  PARAMETERS

A. I. Semenenko, I. A. Semenenko

Institute of Applied Physics NAS, Ukraine, Sumy

  The paper offers an approach to precision determination of three complex parameters ρ, ρ1, ρ2 of the phase compensator of the ellipsometer using an instrument alignment procedure combined with invariant relationships for the ellipsometry of anisotropic media. The alignment procedure allows one to express the small parameters ρ1, ρ2 in terms of the main phase parameter ρ. The substitution of the derived expressions for ρ1, ρ2 into ellipsometry invariants reduces the respective optimization problem to determination of only one complex parameter ρ (two real values) instead of three complex parameters (six real values) in the old technique. This approach dramatically reduces the influence of experimental errors and inhomogeneity of the reflecting surface used to build specimen invariants.