Null ellipsometer with phase modulation

Rotating analyzer–fixed analyzer ellipsometer based on null type ellipsometer

The theory and design of an inexpensive rotating analyzer unit is presented, which allows a conventional null type ellipsometer to work as rotating analyzer–fixed analyzer automatic ellipsometer, without sacrificing the possibility to work in null mode. The mode switching is performed simply by adding or removing the rotating analyzer from its holder. It is shown that the rotating analyzer phas...

A low drift high resolution cryogenic null ellipsometer

A cryogenic ellipsometer capable of measuring submonolayers of liquid helium has been developed. Methods for controlling drift and noise created by the cryostat windows and ellipsometer optics are discussed in detail. The cryostat vacuum windows were made from SF-57 glass due to its low stress-optic coefficient. Custom low-stress vacuum window mounts were designed and all windows were temperatu...

A Retardation Modulation Ellipsometer for Studying Fast Surface Transients

Development of an Automatic Null Ellipsometer for Sputtering Rate Monitoring of EUV Multilayer Fabrication

Instrumentation To overcome current difficulty of absolute period control in the EUV multilayer fabrication by sputtering, we have developed an automatic null ellipsometer as a sputtering rate monitor having high enough picometer thickness sensitivity enabling accurate monitoring of the nm period multilayer fabrication [1]. Figure 1 shows schematic drawing of the ellipsometer installed as the s...

Approximating fully complex spatial modulation with pseudorandom phase-only modulation.

Any desired diffraction pattern can be produced in the Fourier plane by the specification of a corresponding input-plane transparency. Complex-valued transmittance is generally required, but in practice phase-only transmittance is used. Many design procedures use numerically intensive, constrained optimization. We instead introduce a noniterative procedure that directly translates the desired b...