Patent US4512847A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4512847A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of measuring the thickness of the removed layer in subtractive workpiece processing

Assignee: Panasonic Holdings Corp
•
Filing: 1983-10-05
•
Granted: 1985-04-23
•
Expires: 2003-10-05
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A test sample (7) of the same material, or with the same structure as the workpiece (5) exposed to subtractive processing is simultaneously exposed to such processing and consists of a wedge (10) with the angle α covered by two covering plates (11) which are complementary to its two surfaces (14). By measuring the distance x 1 between the thus formed gaps (15), and by comparing it with the original distance x O , thickness z of the respectively removed layer can be determined from the equation ##EQU1##

Inventors

  • 👤 Arwed Brunsch
  • 👤 Wolf-Dieter Ruh
  • 👤 Gerhard Trippel

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 12:59
CPC Classifications
B; B23; B23Q; B23Q17/00; B23Q17/24; G; G01; G01B; G01B11/00; G01B11/02; G01B11/06; G01B5/00; G01B5/02; G01B5/06

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 136 words
The method of measuring the removed layer thickness is subtractive workpiece processing, said method comprising the steps of: processing the workpiece simultaneously with a test sample consisting of the same material as the workpiece, the test sample consisting of a wedge and two covering pieces complementary to the two lateral surfaces of the wedge and protecting the surfaces against the processing; measuring, in the plane of the surface formed by the wedge point and the covering pieces and exposed to processing, the respective distance x 1 between the two gaps which appear between the lateral surfaces of the wedge and the adjacent protecting pieces; and determining the respectively removed layer thickness z 1 from the difference between the original distance x 0 and the measured distance x 1 , taking into consideration the wedge angle α.
Claim 2
Independent Claim 136 words
The method of measuring the removed layer thickness is subtractive workpiece processing, said method comprising the steps of: processing the workpiece simultaneously with a test sample consisting of the same material as the workpiece, the test sample consisting of a wedge and two covering pieces complementary to the two lateral surfaces of the wedge and protecting the surfaces against the processing; measuring, in the plane of the surface formed by the wedge point and the covering pieces and exposed to processing, the respective distance x 1 between the two gaps which appear between the lateral surfaces of the wedge and the adjacent protecting pieces; and determining the respectively removed layer thickness z 1 from the difference between the original distance x 0 and the measured distance x 1 , taking into consideration the wedge angle α.
Claim 3
Dependent Claim 28 words
The method of claim 1 wherein the measuring step is performed by an optical measuring device which produces ouput signal corresponding to the measured distance x 1 .
Claim 4
Dependent Claim 36 words
The method of claim 2 wherein the measuring step is performed, in response to said output signals, by a computer storing the conversion formula ##EQU3## and the original value of the gap distance x 0 .
Claim 5
Dependent Claim 66 words
The method of claim 3 wherein said computer also stores a desired value of the removed layer thickness, comprising the additional step performed after the determining step of comparing the determined removed layer thickness with said desired value of the removed layer thickness and signalling, in response to an equal compare, that the desired etching depth has been reached and the process is to be terminated.
Claim 6
Independent Claim 128 words
The method of measuring the removed layer thickness in subtractive workpiece processing, characterized in that a test sample consisting of the same material as the workpiece is processed simultaneously with the workpiece, the test sample consisting of a wedge and two covering pieces complementary to the two lateral surfaces of the wedge and protecting the surfaces against the processing, that in the plane of the surface formed by the wedge point and the covering pieces and exposed to processing, the respective distance between the two gaps is measured which appear between the lateral surfaces of the wedge and the adjacent protecting pieces, and that the respectively removed layer thickness is determined from the difference between the original distance and the measured distance, taking into consideration the wedge angle.
Claim 7
Independent Claim 128 words
The method of measuring the removed layer thickness in subtractive workpiece processing, characterized in that a test sample consisting of the same material as the workpiece is processed simultaneously with the workpiece, the test sample consisting of a wedge and two covering pieces complementary to the two lateral surfaces of the wedge and protecting the surfaces against the processing, that in the plane of the surface formed by the wedge point and the covering pieces and exposed to processing, the respective distance between the two gaps is measured which appear between the lateral surfaces of the wedge and the adjacent protecting pieces, and that the respectively removed layer thickness is determined from the difference between the original distance and the measured distance, taking into consideration the wedge angle.

References Cited (Backward Citations)

JPS5455377A Cited
US4367044A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1988-04-22 1988-10-22 1989-04-23 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1992-04-22 1992-10-22 1993-04-23 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1996-04-22 1996-10-22 1997-04-23 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag