公开(公告)号：EP0914600A1

公开(公告)日：1999-05-12

申请号：EP97935177.0

申请日：1997-07-22

Applicant: THERMA-WAVE INC.

Inventor： ASPNES, David, E. ,  OPSAL, Jon

IPC: G01N21 ,  G01B11 ,  G01J3 ,  G01J4 ,  G02F1

CPC classification number: G01J3/02 ,  G01J3/0229 ,  G01J3/0232 ,  G01N21/211 ,  G01N2021/213

Abstract: An ellipsometer, and a method of ellipsometry, for analyzing a sample (2) using a broad range of wavelengths, includes a ligth source (4) for generating a beam of polychromatic light for interacting with the sample. A polarizer (6) polarizes the light beam before the light beam interacts with the sample. A rotating compensator (8) induces phase retardations of a polarization state of the light beam wherein the range of wavelengths and the compensator are selected such that at least a first phase retardation value is induced that is within a primary range of effective retardations of substantially 135° to 225°, and at least a second phase retardation value is induced that is outside of the primary range. An analyzer (10) interacts with the light beam after the light beam interacts with the sample. A detector (12) measures the intensity of light after interacting with the analyzer as a function of compensator angle and of wavelength, preferably at all wavelengths simultaneously. A processor (23) determines the polarization state of the analyzer from the light intensities measured by the detector.