Patent ID: 7230701
Filing Date: 2007-06-12
Classification: G01J,G01N

Abstract:
1. Spectroscopic ellipsometer of the type comprising: a source capable of emitting a broadband beam; a polariser to polarise the broadband beam and to produce a polarised incident beam capable of illuminating a spot on a sample according to at least one chosen angle of incidence; an analyser to receive the beam reflected by the sample thus illuminated and to produce an output beam in response to the reflected beam; a detector to convert the output beam into an output signal; processing means to process the output signal and to determine the changes of phase and of amplitude of the state of polarisation of said output beam caused by the reflection of the polarised incident beam on the sample; one of a reflecting optical element and a refracting optical element disposed between the source and the sample and capable of focusing the incident beam according to said spot; and the other of the reflecting optical element and the refracting optical element disposed between the sample and the detector in order to focus said reflected beam to dispose the one of the reflecting optical element and the refracting optical element at a first side of said spot and to dispose the other of the reflecting optical element and the refracting optical element on a second side of said spot and thus to dispose the source and the detector on a same one of the first side and the second side of said spot.