Method for determining parameters of three dimensional nanostructure and apparatus applying the same

Patent metadata

Field	Value
Publication number	US-12493004-B2
Application number	US-202318374289-A
Country	US
Kind code	B2
Filing date	Sep 28, 2023
Priority date	Sep 28, 2022
Publication date	Dec 9, 2025
Grant date	Dec 9, 2025

Abstract

A method for determining parameters of nanostructures, wherein the method includes steps as follows: Firstly, an X-ray reflection intensity measurement curve of a nanostructure to be tested is obtained by radiating the nanostructure to be tested with X-ray. The X-ray reflection intensity measurement curve is compared with an X-ray reflection intensity standard curve to obtain a comparison result. Subsequently, at least one parameter existing in the nanostructure to be tested is determined according to the comparison result.

First claim

What is claimed is:

1 . A method for determining parameters of nanostructures, comprising:
obtaining an X-ray reflection intensity measurement curve of a nanostructure to be tested by radiating the nanostructure to be tested with an X-ray; comparing the X-ray reflection intensity measurement curve with an X-ray reflection intensity standard curve to obtain a comparison result; and determining at least one parameter existing in the nanostructure to be tested according to the comparison result.

2 . The method according to claim 1 , wherein the step of obtaining an X-ray reflection intensity measurement curve comprises:
focusing the X-rays on a surface of the nanostructure to be tested, wherein an incident angle of the X-ray is adjusted within a preset angle range, and an optical wavelength of the X-ray is less than 0.154 nm; using an x-ray detector to collect and measure a total reflection intensity of x-ray reflection lines reflected by the surface; calculating a plurality of non-specular reflection components of the X-ray reflection lines corresponding to different ranges of the incident angle; and removing the non-specular reflection components from the total reflection intensity; and integrating a remained portion of the total reflection intensity to obtain a specular reflection component; and adjust the incident angle with in the preset angle range, repeat above steps, and obtain a relationship curve between the incident angle and the specular reflection component as the X-ray reflection intensity measurement curve.

3 . The method according to claim 2 , wherein the comparison result comprises a difference curve of reflection intensity obtained by subtracting the X-ray reflection intensity standard curve from the X-ray reflection intensity measurement curve.

4 . The method according to claim 3 , wherein the difference curve of reflection intensity comprises a maximum reflection intensity difference at a critical angle of the X-ray reflection intensity measurement curve.

5 . The method according to claim 4 , wherein the step of determining at least one parameter comprises determining a critical dimension deviation in the nanostructure to be tested by referring the maximum reflection intensity difference and an equivalent density function of the X-ray reflection intensity measurement curve.

6 . The method according to claim 5 , wherein the equivalent density function is:

ρ

E
⁢
M
⁢
A

=

∑

i

⁢

A
i

⁢

ρ
i

∑

i

⁢

A
i

wherein, ρEMA is a total equivalent density of the nanostructure to be tested ρ i is an electron density of at least one material constituting the nanostructure to be tested; A i is a surface area of the at least one material on the surface.

7 . The method according to claim 6 , wherein the ρEMA is proportional to the maximum reflection intensity difference.

8 . The method according to claim 6 , further comprising:
obtaining a plurality of reflection intensity simulation curves respectively corresponding to a plurality of structural features, each of which corresponds to at least one parameter of known position, type and/or size; performing a curve fitting on the reflection intensity measurement curve and the plurality of reflection intensity simulation curves, so as to obtain a fitting result; and deducing a position, a type and/or a size of the at least one parameter existing in the nanostructure to be tested by referencing the fitting result.

9 . The method according to claim 1 , wherein the X-ray reflection intensity standard curve is obtained by using the X-rays to irradiate a standard nanostructure which has the same specifications as the nanostructure to be tested, and actually measuring its reflection intensity.

10 . The method according to claim 1 , wherein the X-ray reflection intensity standard curve is obtained by a computer simulation.

11 . An apparatus for determining parameters of nanostructures, comprising:
an X-ray light source, used for emitting an X-ray an X-ray reflector, used to focus the X-ray on a surface of a nanostructure to be tested by adjusting an incident angle of the X-ray within a preset angle range; an X-ray detector, used to collect X-ray reflection lines reflected from surfaces; and a parameters determining module used for:
obtaining an X-ray reflection intensity measurement curve according to a reflection intensity of the X-ray reflection lines;
comparing the X-ray reflection intensity measurement curve with an X-ray reflection intensity standard curve to obtain a comparison result; and
determining at least one parameter existing in the nanostructure to be tested according to the comparison result.

12 . The apparatus according to claim 11 , further comprising an incident slit disposed between the X-ray reflector and the surface; wherein a divergence angle of the X-ray is adjusted by a width of the incident slit.

13 . The apparatus according to claim 11 , further comprising a three-axis moving device used to control a three-axis movement of the X-ray detector in at least one of the X-axis, Y-axis and Z-axis to collect and measure the X-ray reflection lines.

14 . The apparatus according to claim 11 , wherein the X-ray has an optical wavelength less than 0.154 nm.

15 . The apparatus according to claim 11 , wherein the X-ray reflection intensity standard curve is obtained by using the X-rays to irradiate a standard nanostructure which has the same specifications as the nanostructure to be tested, and actually measuring its reflection intensity.

16 . The apparatus according to claim 11 , wherein the X-ray reflection intensity standard curve is obtained by a computer simulation.

Assignees

• Ind Tech Res Inst

Inventors

• Liu Chun-Ting
• He Po-Ching
• Fu Wei-En
• Liu Chun-Yu

Classifications

• H10P74/203

  Structural properties, e.g. testing or measuring thicknesses, line widths, warpage, bond strengths or physical defects · CPC title

• G01N2223/1016

  X-ray · CPC title

• G01B15/04

  for measuring contours or curvatures · CPC title

• G01N2223/052

  reflection · CPC title

• G01N23/2273 Primary

  Measuring photoelectron spectrum, e.g. electron spectroscopy for chemical analysis [ESCA] or X-ray photoelectron spectroscopy [XPS] · CPC title