摘要:
The present invention may include loading a diagnostic sample onto a sample stage, focusing light from an illumination source disposed on a multi-axis stage onto the diagnostic sample, collecting a portion of light reflected from a surface of the diagnostic sample utilizing a detector, wherein the illumination source and the detector are optically direct-coupled via an optical system, acquiring a set of diagnostic parameters indicative of illumination source position drift from the diagnostic sample, determining a magnitude of the illumination source position drift by comparing the acquired set of diagnostic parameters to an initial set of parameters obtained from the diagnostic sample at a previously measured alignment condition, determining a direction of the illumination source position drift; and providing illumination source position adjustment parameters configured to correct the determined magnitude and direction of the illumination source position drift to the multi-axis actuation control system of the multi-axis stage.
摘要:
The present invention may include loading a diagnostic sample onto a sample stage, focusing light from an illumination source disposed on a multi-axis stage onto the diagnostic sample, collecting a portion of light reflected from a surface of the diagnostic sample utilizing a detector, wherein the illumination source and the detector are optically direct-coupled via an optical system, acquiring a set of diagnostic parameters indicative of illumination source position drift from the diagnostic sample, determining a magnitude of the illumination source position drift by comparing the acquired set of diagnostic parameters to an initial set of parameters obtained from the diagnostic sample at a previously measured alignment condition, determining a direction of the illumination source position drift; and providing illumination source position adjustment parameters configured to correct the determined magnitude and direction of the illumination source position drift to the multi-axis actuation control system of the multi-axis stage.
摘要:
The present invention may include an illumination source configured to illuminate a surface of a sample, a detector configured to detect at least a portion of light reflected from the surface of the sample, a selectably configurable optical system comprising: a rotatable polarizing element disposed in the illumination arm of the optical system, an analyzing element disposed in the collection arm of the optical system, and a rotatable-translatable compensator element disposed in the collection arm of the optical system, and a control system communicatively configured to selectably configure the optical system in the a rotating compensator (RCSE) mode, a rotating polarizer (RPSE) mode, or a rotating polarizer and compensator (RPRC) mode.
摘要:
In embodiments of the present invention a second, different waveplate is introduced into a single rotating compensator normal incidence ellipsometer. The second waveplate provides a quarter wavelength retardation that is different from and complementary to that of the first waveplate in order to increase the spectral range for which useful retardation is available, especially towards the deep UV spectrum. The sensitivity for the system may also be increased in the conventional spectral range, since each of the two waveplates may be optimized for its own, somewhat more narrow spectral range of operation. With the proper choice of two waveplates of different retardation, the useful spectral range may be extended from typically 190-820 nm to 150-1000 nm, and beyond if necessary, while increasing the sensitivity within the conventional wavelength range at the same time.
摘要:
Ellipsometry using two waveplates of complementary retardation in a dual rotating compensator configuration is disclosed. Two waveplates of complementary retardation may be used to increase the useful spectral range of a rotating compensator ellipsometer, in particular towards the deep Ultraviolet (UV) spectrum. The improved rotating compensating ellipsometer disclosed herein enables a user to select specific and different waveplate retardations for the purpose of increasing the operating wavelength range of the rotating compensating ellipsometer.