Phase Detection for Nanometer Scale Metal Film’s Thickness Based on SPR Effect
It is found that the phase position of p-component of reflected light changes with the metal film thickness, while the phase position of s-component almost doesn’t change in the Surface Plasmon Resonance effect. S-polarized light is taken as reference and interferometry is adopted to turn the change of the phase position into the change of interference fringes position in the paper, and the film thickness can be derived from it. The simulation results indicated that, through making use of piecewise quadratic fitting on the phase data, the inaccuracy with the range of film thickness is between 30 and 80 nanometers is not more than 0.33 nm.
Jun Hu and Qi Luo
J. D. Xin et al., "Phase Detection for Nanometer Scale Metal Film’s Thickness Based on SPR Effect", Advanced Materials Research, Vol. 320, pp. 377-381, 2011