Charged particle beam apparatus

Patent metadata

Field	Value
Publication number	US-11749494-B2
Application number	US-202117545936-A
Country	US
Kind code	B2
Filing date	Dec 8, 2021
Priority date	Aug 8, 2019
Publication date	Sep 5, 2023
Grant date	Sep 5, 2023

Abstract

A computing unit generates a to-be-used-in-computation netlist on the basis of a to-be-used-in-calculation device model corresponding to a correction sample, estimates a first application result, on the basis of the to-be-used-in-computation netlist and an optical condition, when a charged particle beam is applied to the correction sample under the optical condition, compares the first application result and a second application result based on a detection signal when the charged particle beam is applied to the correction sample under the optical condition, and corrects the optical condition when the first application result and the second application result differ from each other.

First claim

What is claimed is:

1. A control method for a charged particle beam apparatus comprising:
estimating a circuit of a sample or a correction sample using a to-be-used-in-calculation device model under at least one optical condition in which a charged particle beam is applied to the sample or the correction sample;
generating a detection signal based on
secondary electrons emitted from the sample or the correction sample excited by the application of the charged particle beam which is applied to the sample or the correction sample under the at least one optical condition;
generating a to-be-used-in-computation netlist on a basis of the to-be-used-in-calculation device model corresponding to the correction sample;
estimating, on a basis of the to-be-used-in-computation netlist and the at least one optical condition, a first application result when the charged particle beam is applied to the correction sample under the at least one optical condition;
comparing the first application result with a second application result based on the detection signal when the charged particle beam is applied to the correction sample under the at least one optical condition; and
correcting the at least one optical condition when the first application result and the second application result differ from each other.

2. The control method according to claim 1 , wherein said step of correcting the at least one optical condition comprises changing a condition of each of items of the at least one optical condition within a predetermined range in accordance with the comparison result between the first application result and the second application result.

3. The control method according to claim 1 , further comprising:
predetermining a changeable item from among the items of the at least one optical condition; and
correcting the at least one optical condition by changing only a condition of the changeable item.

4. The control method according to claim 1 , wherein
the correction sample includes a plurality of elements, and
said correcting the at least one optical condition is performed on a basis of the first application result and the second application result for each of the plurality of elements.

5. The control method according to claim 1 , wherein said correcting the at least one optical condition comprises correcting a plurality of optical conditions.

6. The control method according to claim 1 , further comprising storing, when the first application result and the second application result coincide with each other, the at least one optical condition after correction in the database with the at least one optical condition after correction associated with the at least one optical condition before correction stored in a database.

7. The control method according to claim 6 , further comprising:
comparing the at least one optical condition before correction and the at least one optical condition after correction to calculate an optical condition correction coefficient for each of the items; and
storing the optical condition correction coefficient in the database with the optical condition correction coefficient associated with the at least one optical condition before correction.

8. The control method according to claim 1 , wherein the to-be-used-in-calculation device model includes a model representing a defect in a device.

9. The control method according to claim 1 , wherein the to-be-used-in-calculation device model includes any one of a model defining a circuit of a device, a mathematical expression defining electrical characteristics of the device, a shape of the device, or physical properties of the device.

10. The control method according to claim 9 , wherein the to-be-used-in-calculation device model includes a parameter value of a circuit element included in the circuit of the device.

11. The control method according to claim 1 , further comprising:
storing a pulse conversion condition under which the charged particle beam is pulsed;
controlling the charged particle beam optical system to control the charged particle beam applied to the sample under the at least one optical condition and the pulse conversion condition; and
estimating the first application result on a basis of the at least one optical condition and the pulse conversion condition.

12. The control method according to claim 1 , wherein
the correction sample is an external sample for which a circuit has been estimated by another of the charged particle beam apparatus, and
the method further comprises storing the to-be-used-in-calculation device model corresponding to the external sample.

13. The control method according to claim 1 , further comprising:
after correcting the optical condition, comparing the first application result and a third application result when the charged particle beam is applied to the correction sample under the at least one optical condition; and
when the first application result and the third application result differ from each other, updating the to-be-used-in-calculation device corresponding to the correction sample.

14. The control method according to claim 13 , further comprising:
changing a parameter value included in the to-be-used-in-calculation device model corresponding to the correction sample; and
updating the to-be-used-in-computation netlist using the parameter value changed.

15. The control method according to claim 1 , wherein the second application result includes at least any one of the detection signal, an inspection image based on the detection signal, the brightness of the inspection image, the brightness of each pixel of the inspection image.

16. A control method of a charged particle beam apparatus comprising:
receiving, by a calculation device, a first input indicating information at least one of a circuit model of an electronic circuit formed on a semiconductor wafer, and a netlist of the electronic circuit;
calculating, by the calculation device, a first inspection condition of a first inspection tool corresponding to at least one of the circuit model or the netlist, and an first inspection result obtained by inspecting the first inspection tool with the first inspection condition based on the first input;
receiving a second inspection result obtained by inspecting the semiconductor wafer corresponding to at least one of the circuit model and the netlist with a second inspection tool setting the first inspection condition; and
adjusting an inspection condition of the second inspection tool with the first inspection result and the second inspection result.

Assignees

• Hitachi High Tech Corp

Inventors

• Miwa Takafumi
• Nakamura Yohei
• Tsuno Natsuki
• KIMIZUKA Heita
• Fukuda Muneyuki

Classifications

• H01J37/22 Primary

  Optical {, image processing} or photographic arrangements associated with the tube · CPC title

• G01N23/2251 Primary

  using incident electron beams, e.g. scanning electron microscopy [SEM] · CPC title

• H01J37/244

  Detectors; Associated components or circuits therefor · CPC title

• G01N2223/07

  secondary emission · CPC title

• G01N2223/507

  secondary-emission detector · CPC title