US5087121A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Depth/height measuring device
Assignee: Canon Inc
•
Filing: 1990-10-01
•
Granted: 1992-02-11
•
Expires: 2010-10-01
Abstract
Abstract A device for measuring depth of a groove formed on an article includes a light source for illuminating the article, a first detector for receiving light from a portion of the article having a groove and being illuminated by the light source, and for detecting a spectral reflectance in relation to the received light, a second detector for receiving light from the article illuminated by the light source and for detecting a spectral reflectance in relation to the received light, the second detector being effective to detect the spectral reflectance in a way not affected or substantially not affected by the groove of the article as compared with the detection by the first detector, and a depth detector for detecting the depth of the groove on the basis of the results of detection by the first and second detectors.
Inventors
- 👤 Osamu Kakuchi
- 👤 Mikichi Ban
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:36
CPC Classifications
G; G01; G01B; G01B11/00; G01B11/22; G01B11/02; G01B11/06; G01B11/0608
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
108 words
A method of measuring the depth of a trench formed on an article having a surface layer, said method comprising the steps of: irradiating with light a first portion of the article without a trench; analyzing light from the irradiated first portion with respect to wavelength to produce first information related to the first portion; irradiating with light a second portion of the article with the trench, different from the first portion; analyzing light from the irradiated second portion with respect to wavelength to produce second information related to the second portion; and determining the depth of the trench on the basis of the first and second information.
Claim 2
Independent Claim
108 words
A method of measuring the depth of a trench formed on an article having a surface layer, said method comprising the steps of: irradiating with light a first portion of the article without a trench; analyzing light from the irradiated first portion with respect to wavelength to produce first information related to the first portion; irradiating with light a second portion of the article with the trench, different from the first portion; analyzing light from the irradiated second portion with respect to wavelength to produce second information related to the second portion; and determining the depth of the trench on the basis of the first and second information.
Claim 3
Dependent Claim
35 words
A method according to claim 1, wherein the first information represents a first spectral reflectivity related to the first portion and wherein the second information represents a second spectral reflectivity related to the second portion.
Claim 4
Dependent Claim
33 words
A method according to claim 2, wherein said determining step includes detecting a difference between the first and second spectral reflectivities and calculating the depth of the trench by using the detected difference.
Claim 5
Dependent Claim
44 words
A method according to claim 3, wherein, for the difference detection, one of the first and second spectral reflectivities is multiplied by a predetermined coefficient and wherein a difference between the result of the multiplication and the other spectral reflectivity is detected by subtraction.
Claim 6
Dependent Claim
49 words
A method according to claim 2, wherein said determination step includes dividing one of the first and second spectral reflectivities by the other, with the one or the other being multiplied by a predetermined coefficient, and calculating the depth of the trench by using the result of the division.
Claim 7
Dependent Claim
75 words
A method according to claim 1, wherein a common analyzer having a predetermined analysis position is used and wherein the analysis of the light from the irradiated first portion is first carried out with the first portion placed at the predetermined analysis position of the analyzer and then the analysis of the light from the irradiated second portion is carried out with the second portion being brought to the predetermined analysis position of the analyzer.
Claim 8
Dependent Claim
30 words
A method according to claim 6, wherein a common illumination device is used to illuminate the first and second portions of the article as placed at the predetermined analysis position.
Claim 9
Dependent Claim
32 words
A method according to claim 1, wherein different analyzers are used for the analysis of the light from the irradiated first portion and of the light from the irradiated second portion, respectively.
Claim 10
Dependent Claim
29 words
A method according to claim 8, wherein different illumination devices in cooperation with the different analyzers, respectively, are used to illuminate different analysis positions of the different analyzers, respectively.
Claim 11
Dependent Claim
29 words
A method according to claim 1, wherein, for the determination of the trench depth, a difference in level between the surface layer top and the trench bottom is calculated.
Claim 12
Dependent Claim
28 words
A method according to claim 10, wherein, for the determination of the trench depth, a thickness of the surface layer is then subtracted from the calculated level difference.
Claim 13
Independent Claim
108 words
An apparatus for measuring the surface height difference of an article having a surface step formed thereon, said apparatus comprising: first examining means for examining with light a first portion of the article without a surface step, and for determining a first spectral characteristic related to the first portion; second examining means for examining with light a second portion of the article with the surface step, different from said first portion, and for determining a second spectral characteristic related to the second portion; and processing means for determining the height difference of the surface step of the article on the basis of the first and second spectral characteristics.
Claim 14
Independent Claim
108 words
An apparatus for measuring the surface height difference of an article having a surface step formed thereon, said apparatus comprising: first examining means for examining with light a first portion of the article without a surface step, and for determining a first spectral characteristic related to the first portion; second examining means for examining with light a second portion of the article with the surface step, different from said first portion, and for determining a second spectral characteristic related to the second portion; and processing means for determining the height difference of the surface step of the article on the basis of the first and second spectral characteristics.
Claim 15
Dependent Claim
43 words
An apparatus according to claim 12, wherein a groove having the depth is formed in the surface of the article as the surface step and wherein said processing means determines the depth of the groove, as the height difference of the surface step.
Claim 16
Dependent Claim
101 words
An apparatus according to claim 12, wherein said first and second examining means include a common spectroscope having an inspection position and a common conveying system for moving the article, and wherein, as the first portion of the article is brought to the inspection position of said spectroscope by said conveying system, said first examining means determines a first spectral reflectivity related to the first portion while, as the second portion of the article is brought to the inspection position of said spectroscope by said conveying system, said second examining means determines a second spectral reflectivity related to the second portion.
Claim 17
Dependent Claim
27 words
An apparatus according to claim 14, wherein said first and second examining means include a common illumination device adapted to illuminate the inspection position of said spectroscope.
Claim 18
Dependent Claim
58 words
An apparatus according to claim 12, wherein said first examining means includes a first spectroscope for detecting a first spectral reflectivity related to the first portion of the article, and wherein said second examining means includes a second spectroscope, different from said first spectroscope, for detecting a second spectral reflectivity related to the second portion of the article.
Claim 19
Dependent Claim
51 words
An apparatus according to claim 16, wherein said first examining means includes a first illumination device for illuminating an inspection position of said first spectroscope and wherein said second examining means includes a second illumination device, different from said first illumination device, for illuminating an inspection position of said second spectroscope.
Claim 20
Dependent Claim
53 words
An apparatus according to claim 12, wherein said first examining means determines a first spectral reflectivity related to the first portion of the article as the first spectral characteristic, and wherein said second examining means determines a second spectral reflectivity related to the second portion of the article as the second spectral characteristic.
Claim 21
Dependent Claim
39 words
An apparatus according to claim 18, wherein said processing means includes means for detecting a difference between the first and second spectral reflectivities and means for calculating the height difference of the surface step by using the detected difference.
Claim 22
Dependent Claim
47 words
An apparatus according to claim 19, wherein said difference detecting means executes the detection through multiplication of one of the first and second spectral reflectivities by a predetermined coefficient and through subtraction for determining a difference between the result of the multiplication and the other spectral reflectivity.
Claim 23
Dependent Claim
55 words
An apparatus according to claim 18, wherein said processing means includes means for dividing one of the first and second spectral reflectivities by the other, with the one or the other being multiplied by a predetermined coefficient, and means for calculating the height difference of the surface step by using the result of the division.
Claim 24
Independent Claim
108 words
An apparatus for measuring with light the depth of a trench of an article having a surface layer, said apparatus comprising: a first light receiving system having first analyzing means, for receiving regularly reflected light from the article and for determining a first spectral characteristic related mainly to the surface layer; a second light receiving system having second analyzing means, for receiving scatteredly reflected light from the article and for determining a second spectral characteristic related to the trench and the surface layer; and processing means for comparing the first and second spectral characteristics and for determining the depth of the trench on the basis of the comparison.
Claim 25
Independent Claim
108 words
An apparatus for measuring with light the depth of a trench of an article having a surface layer, said apparatus comprising: a first light receiving system having first analyzing means, for receiving regularly reflected light from the article and for determining a first spectral characteristic related mainly to the surface layer; a second light receiving system having second analyzing means, for receiving scatteredly reflected light from the article and for determining a second spectral characteristic related to the trench and the surface layer; and processing means for comparing the first and second spectral characteristics and for determining the depth of the trench on the basis of the comparison.
Claim 26
Dependent Claim
34 words
An apparatus according to claim 22, wherein said processing means detects a difference between the first and second spectral characteristics and determines the depth of the trench on the basis of the detected difference.
Claim 27
Dependent Claim
45 words
An apparatus according to claim 23, wherein, for the difference detection, said processing means multiplies one of the first and second spectral characteristics by a predetermined coefficient and then detects a difference between the result of the multiplication and the other spectral characteristic by subtraction.
Claim 28
Dependent Claim
34 words
An apparatus according to claim 22, wherein said processing means divides one of the first and second spectral characteristics by the other, with the one or the other being multiplied by a predetermined coefficient.
Claim 29
Dependent Claim
17 words
An apparatus according to claim 22, further comprising means for determining the thickness of the surface layer.
Claim 30
Dependent Claim
50 words
An apparatus according to claim 22, further comprising illumination means for illuminating the article, wherein said first light receiving means receives regularly reflected light from the article illuminated by said illumination means while said second light receiving means receives scatteredly reflected light from the article illuminated by said illumination means.
Claim 31
Dependent Claim
66 words
An apparatus according to claim 27, wherein said first and second light receiving systems include a common optical system for directing light from the article, a common light receiving portion for receiving the light from said common optical system, and selecting means operable such that the regularly reflected light and the scatteredly reflected light from the article are selectively received by said common light receiving portion.
Claim 32
Dependent Claim
31 words
An apparatus according to claim 22, wherein, for the determination of the trench depth, said processing means calculates a difference in level between the surface layer top and the trench bottom.
Claim 33
Dependent Claim
23 words
An apparatus according to claim 29, wherein said processing means then subtracts a thickness of the surface layer from the calculated level difference.
Claim 34
Independent Claim
175 words
An apparatus for measuring a surface height difference of an article having a surface step formed thereon and a surface layer, said apparatus comprising: a light source; an illumination optical system for illuminating the article with light from said light source; a first light collection optical system for collecting regularly reflected light from the article illuminated by said illumination optical system; a first detecting means for detecting a first spectral characteristic of the light collected by said first light collecting optical system, said first spectral characteristic being related mainly to the surface layer of the article; a second light collecting optical system for collecting scatteredly reflected light from the article illuminated by said illumination optical system; a second detecting means for detecting a second spectral characteristic of the light collected by said second light collecting optical system, said second spectral characteristic being related the surface step and the surface layer of the article; and a processing means for determining the height difference on the basis of a comparison of the first and second spectral characteristics.
Claim 35
Independent Claim
175 words
An apparatus for measuring a surface height difference of an article having a surface step formed thereon and a surface layer, said apparatus comprising: a light source; an illumination optical system for illuminating the article with light from said light source; a first light collection optical system for collecting regularly reflected light from the article illuminated by said illumination optical system; a first detecting means for detecting a first spectral characteristic of the light collected by said first light collecting optical system, said first spectral characteristic being related mainly to the surface layer of the article; a second light collecting optical system for collecting scatteredly reflected light from the article illuminated by said illumination optical system; a second detecting means for detecting a second spectral characteristic of the light collected by said second light collecting optical system, said second spectral characteristic being related the surface step and the surface layer of the article; and a processing means for determining the height difference on the basis of a comparison of the first and second spectral characteristics.
Claim 36
Dependent Claim
32 words
An apparatus according to claim 31, wherein said processing means detects a difference between the first and second spectral characteristics and determines the height difference on the basis of the detected difference.
Claim 37
Dependent Claim
42 words
An apparatus according to claim 32, wherein, for the difference detection, said processing means multiplies one of the first and second spectral characteristics by a predetermined coefficient and detects a difference between a result of the multiplication and the other spectral characteristic.
Claim 38
Dependent Claim
41 words
An apparatus according to claim 31, wherein for the determination of the height difference, said processing means divides one of the first and second spectral characteristics by the other, with the one or the other being multiplied by a predetermined coefficient.
Claim 39
Dependent Claim
56 words
An apparatus according to claim 31, wherein said first and second detecting means includes a common spectroscope, and wherein said first and second light collecting optical systems include a common lens system and a common light selecting element by which the regularly reflected light and the scatteredly reflected light are selectively received by said common spectroscope.
Claim 40
Dependent Claim
32 words
An apparatus according to claim 31, wherein, for the determination of the height difference, said processing means calculates a difference in level between the surface layer top and the surface step bottom.
Claim 41
Dependent Claim
23 words
An apparatus according to claim 36, wherein said processing means then subtracts a thickness of the surface layer from the calculated level difference.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-02-10 | 1995-08-12 | 1996-02-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-02-10 | 1999-08-12 | 2000-02-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-02-10 | 2003-08-12 | 2004-02-11 | $7700.00 | Window Closed / Lapsed |