Kla Tencor Corporation

Kla-tencor Technologies Corporation

Lionel Kuhlmann

Henrik Nielsen

Mark A Nokes

Wayne McMillan

Jianbo Gao

Mark C Sweeney

A linear position array detector system is provided which imparts light energy to a surface of a specimen, such as a semiconductor wafer, receives light energy from the specimen surface and monitors deviation of the retro or reflected beam from that expected to map the contours on the specimen surface. The retro beam will, with ideal optical alignment, return along the same path as the incident beam if and only if the surface is normal to the beam. The system has a measurement device or sensor within the path of the retro or reflected beam to measure deviation of the retro beam from expected. The sensor is preferably a multiple element array of detector-diodes aligned in a linear fashion. A unique weighting and summing scheme is provided which increases the mechanical dynamic range while preserving sensitivity. The system further includes a bright field Nomarski Differential Interference Contrast sensor used to split the beam into two beams and for scanning in an orientation orthogonal to the orientation of the optical lever created by the system.

Detection system for nanometer scale topographic measurements of reflective surfaces

Methods for inspecting a wafer are provided. One method includes directing light to a center portion and an edge portion of a wafer in a single scan. The method also includes detecting light scattered from the center portion using a first detection channel and detecting light scattered from the edge portion using a second detection channel. Another method for inspecting an edge portion of a wafer includes scanning the edge portion of the wafer with light. The method also includes separately detecting different portions of light scattered from the edge portion. In addition, the method includes separating light scattered from edge features in the edge portion from other light scattered from the edge portion. The method further includes detecting defects in the edge portion of the wafer using the other scattered light.

Methods and systems for inspection of an entire wafer surface using multiple detection channels

Disclosed are methods and apparatus for analyzing the Raze data provided by an optical inspection tool. The Haze data is analyzed so as to detect defects associated with the specimen surface. In general, the Haze data is first conditioned so that background noise which corresponds to low frequency variation on the specimen is separated or removed from the Haze data prior to analysis of such Haze data. In a specific embodiment, low frequency variations in the specimen surface are characterized, in effect, as an optical surface upon which an incident beam is directed. The Haze data that conforms to this resulting polynomial equation is then subtracted from the original Haze data to result in residual data, where slow variations in surface roughness are subtracted out, leaving possible defect information in the residual Haze data. This residual Haze data may then be analyzed to determine whether the specimen contains a defect.

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San Jose, CA, United States of America

Lionel Kuhlmann