The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 28, 2011
Filed:
Nov. 22, 2006
Daniel Ian Mansfield, Leicester, GB;
Daniel Ian Mansfield, Leicester, GB;
Taylor Hobson Limited, Leicester, GB;
Abstract
A coherence scanning interferometer () carries out: a coherence scanning measurement operation on a surface area () carrying a structure using a low numeric aperture objective so that the pitch of the surface structure elements () is much less that the spread of the point spread function at the surface () to obtain structure surface intensity data; and a coherence scanning measurement operation on a non-structure surface area (), which may be part of the same sample or a different sample, to obtain non-structure surface intensity data. A frequency transform ratio determiner () determines a frequency transform ratio (the HCF function) related to the ratio between the structure surface intensity data and the non-structure surface intensity data. A structure provider () sets that frequency transform ratio equal to an expression which represents the electric field at the image plane of the coherence scanning interferometer in terms of surface structure element size (height or depth) and width-to-pitch ratio and derives the surface structure element size and width-to-pitch ratio using the frequency transform ratio. The structure provider () may also extract the surface structure element width, if the pitch is independently known.