Method and apparatus to fold optics in tools for measuring shape and/or thickness of a large and thin substrate

• Main Authors: ZENG ANDREW AN, WANG CHUNHAI, ZHANG YI, GOODMAN FREDERICK ARNOLD, HUANG CHUNSHENG, TANG SHOUHONG
• Format: Patent
• Language: English
• Published: 08.03.2016
• Subjects: MEASURING; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS; MEASURING LENGTH, THICKNESS OR SIMILAR LINEARDIMENSIONS; PHYSICS; TESTING

A semiconductor measuring tool has a folding mirror configuration that directs a light beam to pass the same space multiple times to reduce the size and footprint. Furthermore, the folding mirrors may reflect the light beam at less than forty-five degrees; thereby allowing for smaller folding mirror...