公开(公告)号：US20180209784A1

公开(公告)日：2018-07-26

申请号：US15329778

申请日：2016-11-04

Applicant: KLA-Tencor Corporation

Inventor： Guoheng Zhao ,  Maarten van der Burgt ,  Sheng Liu ,  Andy Hill ,  Johan De Greeve ,  Karel van Gils

IPC: G01B11/25 ,  G01B11/06

CPC classification number: G01B11/2518 ,  G01B11/0608 ,  G01B11/24 ,  G01B11/2513 ,  G01B11/2522 ,  G01B2210/56

Abstract: For three-dimensional topography measurement of a surface of an object patterned illumination is projected on the surface through an objective. A relative movement between the object and the objective is carried out, and plural images of the surface are recorded through the objective by a detector. The direction of the relative movement includes an oblique angle with an optical axis of the objective. Height information for a given position on the surface is derived from a variation of the intensity recorded from the respective position. Also, patterned illumination and uniform illumination may be projected alternatingly on the surface, while images of the surface are recorded during a relative movement of the object and the objective along an optical axis of the objective. Uniform illumination is used for obtaining height information for specular structures on the surface, patterned illumination is used for obtaining height information on other parts of the surface.

公开(公告)号：US20170276613A1

公开(公告)日：2017-09-28

申请号：US15468608

申请日：2017-03-24

Applicant: KLA-Tencor Corporation

Inventor： Sheng Liu ,  Guoheng Zhao

IPC: G01N21/88 ,  G01N21/95 ,  G01N21/21

CPC classification number: G01N21/8806 ,  G01N21/21 ,  G01N21/9501 ,  G01N2021/8848 ,  G01N2201/0683

Abstract: Disclosed are methods and apparatus for inspecting a semiconductor sample. This system comprises an illumination optics subsystem for generating and directing an incident beam towards a defect on a surface of a wafer. The illumination optics subsystem includes a light source for generating the incident beam and one or more polarization components for adjusting a ratio and/or a phase difference for the incident beam's electric field components. The system further includes a collection optics subsystem for collecting scattered light from the defect and/or surface in response to the incident beam, and the collection optics subsystem comprises an adjustable aperture at the pupil plane, followed by a rotatable waveplate for adjusting a phase difference of electric field components of the collected scattered light, followed by a rotatable analyzer. The system also includes a controller that is configured for (i) selecting a polarization of the incident beam, (ii) obtaining a defect scattering map, (iii) obtaining a surface scattering map, and (iv) determining a configuration of the one or more polarization components, aperture mask, and rotatable ¼ waveplate, and analyzer based on analysis of the defect and surface scattering map so as to maximize a defect signal to noise ratio,