US 12,352,569 B2
Broadband profiler system and method for constructing a three-dimensional profile of a target
Kam Chiu Lau, Rockville, MD (US); Yongwoo Park, Rockville, MD (US); Po Shan Chan, Hong Kong (HK); Man Wai Cheng, Hong Kong (HK); Fei Yeung, Hong Kong (HK); and Qi Lang, Hong Kong (HK)
Assigned to AP Infosense Limited, Hong Kong (HK)
Appl. No. 18/025,650
Filed by AP Infosense Limited, Hong Kong (HK)
PCT Filed Jun. 2, 2022, PCT No. PCT/IB2022/055158
§ 371(c)(1), (2) Date Mar. 10, 2023,
PCT Pub. No. WO2023/084322, PCT Pub. Date May 19, 2023.
Claims priority of application No. 32021042425.7 (HK), filed on Nov. 12, 2021.
Prior Publication US 2024/0288261 A1, Aug. 29, 2024
Int. Cl. G01B 9/02015 (2022.01); G01B 9/02 (2022.01); G01B 9/02055 (2022.01); G01B 9/02091 (2022.01); G01B 11/24 (2006.01)
CPC G01B 9/02015 (2013.01) [G01B 9/02064 (2013.01); G01B 9/02065 (2013.01); G01B 9/02083 (2013.01); G01B 9/02091 (2013.01); G01B 11/24 (2013.01)] 8 Claims
OG exemplary drawing
 
1. An optical system for reconstructing a three-dimensional morphology of a sample, the system comprising:
a broadband radiation source;
an interferometric system configured to receive the radiation from the broadband radiation source, wherein the interferometric system comprises:
a first beam splitter, a moving time delay-inducing reflector, and a stationary reflector, wherein the radiation is directed to the first beam splitter, and wherein the first beam splitter transmits half of the radiation to the stationary reflector, creating an optical reference incident radiation, and reflects half of the radiation to the moving time delay- inducing reflector, creating a time-delayed optical sample incident radiation; and
a second beam splitter receiving the optical reference incident radiation and the time-delayed optical sample incident radiation;
a stationary sample holder for receiving the time-delayed optical sample incident radiation reflected from the second beam splitter, resulting in reflected or scattered optical sample radiation, wherein the second beam splitter further receives reflected or scattered optical sample radiation from the stationary sample holder;
a reference plane for receiving the optical reference incident radiation which passes through the second beam splitter, resulting in reflected or scattered optical reference radiation, wherein the second beam splitter further receives reflected or scattered optical reference radiation from the reference plane, and wherein a first optical path between the second beam splitter and the stationary sample holder is spatially separated from a second optical path between the second beam splitter and the reference plane;
a detector configured to receive an interference signal generated by the second beam splitter from the reflected or scattered optical sample radiation and the reflected or scattered optical reference radiation; and
a processor for extracting an optical path difference between the reference plane and the sample and generating a three-dimensional morphology of the sample;
the processor generating an x-y plane image for each sample z-direction thickness, the irradiance for each pixel in the x-y plane image being registered and a fringe localization position of that pixel being determined by a series of pre-processing, processing, and post-processing stages, wherein in the pre-processing stage, image filtering algorithms are applied to minimize dispersion imbalance, phase change and system vibration with the system, in the processing stage, a fast envelope and peak detection algorithm is applied to determine a surface and multilayer properties in which a generated point cloud is analyzed by clustering and segmentation machine learning to group points having common characteristics and to denoise each x-y plane image and wherein plural generated x-y plane images are combined in the z-direction to create the three-dimensional morphology of the sample.