Charged particle beam apparatus

Patent metadata

Field	Value
Publication number	US-11646172-B2
Application number	US-202117545944-A
Country	US
Kind code	B2
Filing date	Dec 8, 2021
Priority date	Aug 8, 2019
Publication date	May 9, 2023
Grant date	May 9, 2023

Abstract

A charged particle beam apparatus includes a database that stores a to-be-used-in-calculation device model for use in estimation of a circuit of a sample and an optical condition under which a charged particle beam is applied to the sample, a charged particle beam optical system that controls the beam applied to the sample under the optical condition, a detector that detects secondary electrons emitted from the sample excited by the application of the beam and outputs a detection signal based on the secondary electrons, and a computing unit that generates a to-be-used-in-computation netlist based on the to-be-used-in-calculation device model, estimates a first application result when the beam is applied to the sample based on the to-be-used-in-computation netlist and the optical condition, and compares the first application result with a second application result when the beam is applied to the sample based on the optical condition.

First claim

What is claimed is:

1. A method of performing calculation related to a charged particle beam apparatus, the method comprising:
a first step of a processor storing, in a memory, a to-be-used-in-calculation device model for use in estimation of a circuit of a sample and an optical condition under which a charged particle beam is applied to the sample;
a second step of the processor controlling the charged particle beam applied to the sample under the optical condition by controlling a charged particle beam system comprising a lens barrel mounted on a sample chamber;
a third step of detecting, using a detector, secondary electrons emitted from the sample excited by the application of the charged particle beam, and outputting, by the detector to the processor, a detection signal based on the secondary electrons;
a fourth step of the processor storing, in the memory, the detection signal on a basis of secondary electrons emitted from the sample by an application of the charged particle beam applied to the sample under the optical condition; and
a fifth step of the processor generating-a to-be-used-in-computation netlist on a basis of the to-be-used-in-calculation device model, estimating a first application result when the charged particle beam is applied to the sample on a basis of the to-be-used-in-computation netlist and the optical condition, and comparing the first application result with a second application result when the charged particle beam is applied to the sample on a basis of the optical condition.

2. The method according to claim 1 ,
wherein the fifth step further comprises updating, by the processor, the to-be-used-in-calculation device model when the first application result and the second application result differ from each other, and identifying the to-be-used-in-computation netlist as a netlist describing the circuit of the sample when the first application result and the second application result coincide with each other.

3. The method according to claim 2 ,
wherein the fifth step further comprises changing, by the processor, a parameter value included in the to-be-used-in-calculation device model, and updating the to-be-used-in-computation netlist using the parameter value changed.

4. The method according to claim 2 ,
wherein fourth step further comprises generating, by the processor, an inspection image on a basis of the detection signal, and
generating, by the processor, a correspondence table that associates a position of a plug electrode in the inspection image with each node in the to-be-used-in-computation netlist identified.

5. The method according to claim 1 ,
wherein the fifth step further comprises comparing, by the processor, any one of the detection signal, an inspection image based on the detection signal, a brightness of the inspection image, and a brightness of each pixel of the inspection image, of the first application result with the second application result.

6. The method according to claim 1 ,
wherein the first step of the processor storing the to-be-used-in-calculation device model further comprises storing, by the processor, the to-be-used-in-calculation device model including a model representing a defect in a device.

7. The method according to claim 1 ,
wherein the first step of the processor storing the to-be-used-in-calculation device model further comprises storing, by the processor, the to-be-used-in-calculation device model including 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, and physical properties of the device.

8. The method according to claim 7 ,
wherein the first step of the processor storing the to-be-used-in-calculation device model further comprises storing, by the processor, the to-be-used-in-calculation device model including a parameter value of a circuit element included in the circuit of the device.

9. The method according to claim 1 , further comprising a step of the processor storing, in the memory,
a pulse conversion condition under which the charged particle beam is pulsed,
wherein the processor estimates the first application result based on the optical condition, which controls the charged particle beam applied to the sample, and the pulse conversion condition.

10. The method according to claim 1 ,
wherein fourth step of comparing further comprises comparing, by the processor, using a plurality of the to-be-used-in-calculation device models and one of the optical conditions, the first application result and the second application result for each of the to-be-used-in-calculation device models.

11. The method according to claim 1 ,
wherein fourth step of comparing further comprises comparing, by the processor, using one of the to-be-used-in-calculation device models and a plurality of the optical conditions, the first application result and the second application result for each of the optical conditions.

12. A method of outputting a display related to a charged particle beam apparatus, the method comprising:
generating a to-be-used-in-computation netlist based on a to-be-used-in-calculation device model for use in estimating a circuit of a sample;
applying a charged particle beam estimated from the to-be-used-in-computation netlist and an optical condition to a sample;
estimating a first application result from the charged particle beam being applied to the sample;
estimating a second application result from the charged particle beam being applied to the sample on the basis of the first application result and the optical condition; and
displaying, by a processor, a first application result and a second application result on a display,
wherein said displaying of the first application result or the second application result includes at least one of
a detection signal which is based on secondary electrons emitted from the sample by the application of the charged particle beam applied to the sample under the optical condition;
a waveform indicating the detection signal;
an inspection image which is based on the detection signal;
brightness of the inspection image;
brightness of each pixel of the inspection image;
an estimated netlist; and
a circuit diagram.

13. The method according to claim 12 ,
wherein said displaying of the first application result or the second application result further comprises displaying at least one of the to-be-used-in-calculation device model for use in estimation of the circuit of the sample, and the optical condition of the charged particle beam applied to the sample.

14. A method related to a charged particle beam apparatus, the method comprising:
a step of estimating a first inspection result by irradiating a sample forming an electric circuit with an electron beam using an inspection tool;
a step of estimating a second inspection result of the electric circuit based on a netlist of the electric circuit or a circuit model which is based on the netlist;
a step of a processor receiving, as a first input, the first inspection result estimated when a sample forming the electric circuit is inspected using the inspection tool;
a step of the processor receiving, as a second input, the second inspection result of the electric circuit obtained from the netlist of the electric circuit or the circuit model which is based on the netlist; and
a step of the processor updating at least one of the netlist and the circuit model according to the first input.

Assignees

• Hitachi High Tech Corp

Inventors

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

Classifications

• H01J2237/221

  Image processing · CPC title

• H01J37/28

  with scanning beams {(H01J37/268, H01J37/292, H01J37/2955 take precedence)} · CPC title

• H01J37/24 Primary

  Circuit arrangements not adapted to a particular application of the tube and not otherwise provided for · CPC title

• H01J37/153 Primary

  Electron-optical or ion-optical arrangements for the correction of image defects, e.g. stigmators · CPC title

• H01J2237/2817

  Pattern inspection · CPC title