Integrated local and global optical metrology for samples having miniature features

Abstract

This invention relates to an apparatus and method for integrated measurement of a sample that has miniature features. The apparatus has an optical measuring unit for illuminating the sample with a global test radiation over an optical test region and obtaining an optical response, such as scattered or transmitted radiation from the optical test region. In addition, the apparatus has a local measuring unit for making a nanometer scale measurement of a local material parameter ρ of the sample. The local parameter ρ is determined with a mechanical, optical, magnetic, electric or other physical measurement performed in the nanometer range with a scanning probe tip at a test location lying within the optical test region. The material parameter ρ is selected such that it is substantially constant or uniform over the illuminated area. A computational unit determines a property of the miniature features within the optical test region from the optical response supplemented with an adjustment derived from the local material parameter obtained by the local measuring unit.