Patent ID: 9658151
Date: 2017-05-23
CPC Classifications: G01N,H04N

Claim:
1. A camera system (C) for viewing, as opposed to providing a beam (B) of electromagnetic radiation to conduct measurements on a surface of a sample (SAM), in functional combination with a reflectometer, ellipsometer, polarimeter or the like system (ES): wherein said reflectometer, ellipsometer, polarimeter or the like system (ES) comprises: such that in use said illuminating source (LS) of a beam of electromagnetic radiation causes a beam of electromagnetic radiation to interact with a sample (SAM) placed on said stage (STG) and reflect into said detector (DET), such that sample characterizing data is produced thereby, said beam of electromagnetic radiation defining an “X”-“Z” plane in an orthogonal “X”, “Y” and “Z” axis system; and said camera system (C) for monitoring the surface of said sample comprises: each of said camera sensor plate (CS), focusor (FM) and sample supporting stage (STG) each being oriented in identifiable planes, wherein: such that in use when said camera (C) is positioned to observe a sample placed on said stage for supporting a sample along a camera viewpoint locus (VL), said camera viewpoint locus forms an angle alpha ( ) with respect to the plane of said camera sensor plate, and proceeds from said camera sensor plate along a substantial perpendicular to the plane of said focusor and along its optical axis, and such that said camera viewpoint locus further forms an oblique angle of incidence beta ( ) with respect to a normal to a surface of said sample, said camera being offset in both “Y”, and “Z” directions from said “X”-“Z” plane; said camera sensor plate (CS), focusor (FM) and stage (STG) for supporting a sample (SAM) being oriented with respect to one another such that a projected perpendicular to the plane of the camera sensor plate, a projected plane of the sample (SAM) surface and a projected plane of the focusor (FM) intersect at a common point, and such that the following condition is substantially met: where “X” is the distance from the camera sensor plate (CS), at the point at which said beam passes therethrough, to a center of said focusor (FM), and “f” is the focal length of said focusor (FM) and where alpha (α) and beta (β) were defined above; such that, in use the camera (C) provides a focused view of the sample (SAM) over the area thereof viewed, while ellipsometric or the like data is acquired at small angles-of-incidence that are unatainable when the camera is present along the “Z” axis where it physically interferes with the positioning of said illuminating source (SAM) of a beam of electromagnetic radiation and said detector; said system further including a contrast developing system comprising: such that in use said camera illuminating source (S) directs a beam of electromagnetic radiation at said first beam splitter (BS