Mark W Smith
Landscape Architect at Congress Ave, Austin, TX

2006019, Sep 7, 2006

Feb 27, 2006

11/363755

Aviv Frommer - D.N. Misgav, IL
Vladimir Levinski - Nazareth llit, IL
Mark Smith - Austin TX, US
Jeffrey Byers - Lexington TX, US
Chris Mack - Austin TX, US
Michael Adel - Zichron Ya'akov, IL

G01B 11/00

356401000

In one embodiment, a system for imaging an acquisition target or an overlay or alignment semiconductor target is disclosed. The system includes a beam generator for directing at least one incident beam having a wavelength λ towards a periodic target having structures with a specific pitch p. A plurality of output beams are scattered from the periodic target in response to the at least one incident beam. The system further includes an imaging lens system for passing only a first and a second output beam from the target. The imaging system is adapted such that the angular separation between the captured beams, λ, and the pitch are selected to cause the first and second output beams to form a sinusoidal image. The system also includes a sensor for imaging the sinusoidal image or images, and a controller for causing the beam generator to direct the at least one incident beam towards the periodic target or targets, and for analyzing the sinusoidal image or images. In one application the detector detects a sinusoidal image of an acquisition target with the same pitch as the designed target and the controller analyzes the pitch of the sinusoidal image compared to design data to determine whether the target has been successfully acquired. In a second application a first and second periodic target that each have a specific pitch p are imaged so that the detector detects a first sinusoidal image of the first target and a second sinusoidal image of the second target and the controller analyzes the first and second sinusoidal image to determine whether the first and second targets have an overlay or alignment error.