Inspection method and inspection apparatus

Patent metadata

Field	Value
Publication number	US-10698006-B2
Application number	US-201615548860-A
Country	US
Kind code	B2
Filing date	Feb 2, 2016
Priority date	Feb 10, 2015
Publication date	Jun 30, 2020
Grant date	Jun 30, 2020

Abstract

An inspection apparatus includes a tester unit that applies a stimulus signal to a semiconductor apparatus, an MO crystal arranged to face a semiconductor apparatus, a light source that outputs light, an optical scanner that irradiates the MO crystal with light output from light source, a light detector that detects light reflected from the MO crystal arranged to face the semiconductor apparatus D and outputs a detection signal, and a computer that generate phase image data based on a phase difference between a reference signal generated based on a stimulus signal and the detection signal, the phase image data including a phase component indicating the phase difference, and generates an image indicating a path of a current from the phase image data.

First claim

The invention claimed is:

1. An inspection method for acquiring a path of a current generated in a semiconductor device by applying a stimulus signal to the semiconductor device, the inspection method comprising:
applying the stimulus signal to the semiconductor device;
irradiating a magneto-optical crystal disposed facing the semiconductor device with light;
detecting light reflected from the magneto-optical crystal and outputting a detection signal; generating phase image data based on a phase difference between a reference signal generated based on the stimulus signal and the detection signal, the phase image data comprising a phase component indicating the phase difference; and
generating an image indicating the path of the current based on the phase image data, wherein generating the image indicating the path of the current comprises generating statistical value image data by calculating a statistical value of the phase component based on luminance of pixels included in a portion of the phase image data and mapping statistical values of each of the pixels, and generating the image indicating the path of the current based on the statistical value image data.

2. The inspection method according to claim 1 ,
wherein generating the image indicating the path of the current comprises generating sine image data indicating a sine component and cosine image data indicating a cosine component based on the phase image data, and generating the image indicating the path of the current based on the sine image data and the cosine image data.

3. The inspection method according to claim 2 ,
wherein generating the image indicating the path of the current comprises performing calculation of any one of addition, multiplication, and a square root of sum of squares on the sine image data and the cosine image data.

4. The inspection method according to claim 2 ,
wherein generating the image indicating the path of the current comprises:
generating sine statistical value image data indicating a statistical value of the sine component based on the sine image data, generating cosine statistical value image data indicating a statistical value of the cosine component based on the cosine image data, and generating the image indicating the path of the current based on the sine statistical value image data and the cosine statistical value image data.

5. The inspection method according to claim 1 ,
wherein the statistical value is any one of variance, skewness, and kurtosis.

6. The inspection method according to claim 1 ,
wherein the reference signal is a signal having the same phase and cycle as the stimulus signal.

7. An inspection apparatus for acquiring a path of a current generated in a semiconductor device by applying a stimulus signal to the semiconductor device, the inspection apparatus comprising:
a tester configured to apply the stimulus signal to the semiconductor device;
a magneto-optical crystal configured to be disposed facing the semiconductor device;
a light source configured to output light; an irradiation optical system configured to irradiate the magneto-optical crystal with the light output from the light source;
a light detector configured to detect light reflected from the magneto-optical crystal, and output a detection signal;
an analyzer configured to generate phase image data based on a phase difference between a reference signal generated based on the stimulus signal and the detection signal, the phase image data comprising a phase component indicating the phase difference; and
a current path image generator configured to generate an image indicating the path of the current based on the phase image data, wherein
the current path image generator generates statistical value image data by calculating a statistical value of the phase component based on luminance of pixels included in a portion of the phase image data and mapping statistical values of each of the pixels, and generates the image indicating the path of the current based on the statistical value image data.

8. The inspection apparatus according to claim 7 ,
wherein the current path image generator generates sine image data indicating a sine component and cosine image data indicating a cosine component based on the phase image data, and generates the image indicating the path of the current based on the sine image data and the cosine image data.

9. The inspection apparatus according to claim 7 ,
wherein the current path image generator performs calculation of any one of addition, multiplication, and a square root of sum of squares on the sine image data and the cosine image data.

10. The inspection apparatus according to claim 8 ,
wherein the current path image generator generates sine statistical value image data indicating a statistical value of the sine component based on the sine image data, generates cosine statistical value image data indicating a statistical value of the cosine component based on the cosine image data, and generates the image indicating the path of the current based on the sine statistical value image data and the cosine statistical value image data.

11. The inspection apparatus according to claim 7 ,
wherein the statistical value is any one of variance, skewness, and kurtosis.

12. The inspection apparatus according to claim 7 ,
wherein the reference signal is output from the tester.

13. The inspection apparatus according to claim 7 ,
wherein the reference signal is output from the semiconductor device.

14. The inspection apparatus according to claim 7 ,
wherein the reference signal is a signal having the same phase and cycle as the stimulus signal.

Assignees

• Hamamatsu Photonics Kk

Inventors

• Nakamura Tomonori
• Otaka Akihiro

Classifications

• G01R31/311 Primary

  of integrated circuits {(G01R31/31728 takes precedence)} · CPC title

• G01N2021/8887

  based on image processing techniques · CPC title

• G01N29/48

  by amplitude comparison · CPC title

• G01N29/449

  Statistical methods not provided for in G01N29/4409, e.g. averaging, smoothing and interpolation · CPC title

• G01N21/8851 Primary

  Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges (G01N21/8806 and G01N21/93 - G01N21/95692 take precedence; optical measurement of dimensions G01B11/00; optical scanning G02B26/10; image transformation G06T3/00; computerised image enhancement G06T5/00; image processing per se for flaw detection G06T7/0002) · CPC title