System and method for inspecting a workpiece surface by analyzing scattered light in a back quartersphere region above the workpiece

Abstract

A surface inspection system includes a beam source subsystem, a beam scanning subsystem, a workpiece movement subsystem, an optical collection and detection subsystem, and a processing subsystem. The optical collection and detection system features back collectors disposed in the back quartersphere, outside the incident plane, for collecting light scattered from the surface of the workpiece. The back collectors are disposed at a relative minimum in the portion of scattered light attributable to haze relative to the portion of scattered light attributable to defect scatter portion, or, alternatively, at a relative minimum in the Rayleigh scatter.

Description

CROSS-REFERENCE TO RELATED APPLICATION [0001] The present application claims the benefit of the filing date of U.S. Provisional Patent Application No. 60 / 638,529, filed Dec. 19, 2004, currently pending, the entire disclosure of which is incorporated herein by reference.STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT [0002] N / A BACKGROUND OF THE INVENTION [0003] 1. Field of the Invention [0004] The present invention relates to technology for the inspection of a surface or surfaces of a workpiece, such as a semiconductor wafer, chip, or the like. More particularly, it relates to apparatus and methods for inspection of such workpiece surfaces using electromagnetic energy, e.g., light, to scan the surface to obtain characteristics of the surface or other information concerning the surface. [0005] 2. Description of the Related Art [0006] There are a number of applications in which it is desirable or advantageous to inspect a surface or surfaces of a workpiece to obtain in...

AI Technical Summary

Benefits of technology

[0010] Accordingly, an object of the present invention according to one aspect is to provide apparatus and methods for inspecting a surface of a workpiece with high sensitivity and reliability, e.g., for surface defects.

[0011] Another object of the invention according to another aspect is to provide apparatus and methods for inspecting a surface of a workpiece that enable an improved range of detection for surface characteristics, such as defects, defect type, etc., relative to known systems and methods.

Problems solved by technology

This often causes changes in the amplitude and direction of scattered light from the scratch as the wafer rotates.

This highly controlled environment limits normal access to such machines and systems, which increases the difficulty and expense of their maintenance and repair.

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