	US 12,265,212 B2
	3D microscope including insertable components to provide multiple imaging and measurement capabilities
James Jianguo Xu, San Jose, CA (US); Ken Kinsun Lee, Los Altos Hills, CA (US); Rusmin Kudinar, Fremont, CA (US); Ronny Soetarman, Fremont, CA (US); Hung Phi Nguyen, Santa Clara, CA (US); and Zhen Hou, Fremont, CA (US)
Assigned to KLA-Tencor Corporation, Milpitas, CA (US)
Filed by KLA-Tencor Corporation, Milpitas, CA (US)
Filed on Nov. 28, 2022, as Appl. No. 18/070,389.
Application 18/070,389 is a division of application No. 17/109,528, filed on Dec. 2, 2020, granted, now 11,536,940.
Application 17/109,528 is a division of application No. 16/056,860, filed on Aug. 7, 2018, granted, now 10,884,228, issued on Jan. 5, 2021.
Application 16/056,860 is a division of application No. 13/333,938, filed on Dec. 21, 2011, granted, now 10,048,480, issued on Aug. 14, 2018.
Claims priority of provisional application 61/430,937, filed on Jan. 7, 2011.
Prior Publication US 2023/0087619 A1, Mar. 23, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G02B 21/06 (2006.01); G02B 21/00 (2006.01); G02B 21/36 (2006.01)

CPC G02B 21/06 (2013.01) [G02B 21/0092 (2013.01); G02B 21/367 (2013.01)]

1 Claim

1. A method of 3D imaging or measuring a sample, the method comprising:

acquiring a 3D image of a flat reference surface devoid of any features by varying a relative distance between the reference surface and an objective lens at a first plurality of predetermined steps;

at first predetermined steps:

at each of a first set of predetermined steps of the first plurality of predetermined steps:

projecting an image of a patterned article onto a focal plane of the objective lens;

capturing a first image with a pattern associated with the patterned article and the reference surface, and storing the first image in a first image array;

at each of a second set of predetermined steps of the first plurality of predetermined steps:

capturing a second image of the reference surface without the pattern associated with the patterned article, and storing the second image in a second image array;

generating a 3D image of the reference surface by analyzing the first and second images;

acquiring a 3D image of the sample by varying a relative distance between the sample and the objective lens at a second plurality of predetermined steps;

at each of a third set of predetermined steps of the second plurality of predetermined steps:

projecting an image of a patterned article onto a focal plane of the objective lens;

capturing a third image with a pattern associated with the patterned article and the sample, and storing the third image in a third image array;

at each of a fourth set of predetermined steps of the second plurality of predetermined steps:

capturing a fourth image of the sample without the pattern associated with the patterned article, and storing the fourth image in a fourth image array;

generating a 3D image of the sample by analyzing the third and fourth images; and

subtracting the 3D image of the sample with the 3D image of the reference surface to yield a final 3D image and measurement results of the sample.