Patent DE360592C successfully refreshed from Google Patents.
Patent US5485080A successfully refreshed from Google Patents.
US5485080A
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US
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Non-contact measurement of linewidths of conductors in semiconductor device structures
Assignee: United States, AS REPRESENTED BY DEPARTMENT OF COMMERCE COMMERCE, Secretary of
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Filing: 1993-09-08
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Granted: 1996-01-16
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Expires: 2013-09-08
Abstract
Abstract A method of measuring the linewidth of an electrical conductor on a semiconductor substrate includes preparing mutually separated test and interconnection areas on a surface of a semiconductor substrate; forming an electrical interconnection conductor on the surface of the substrate in the interconnection area with a substantially uniform linewidth electrically interconnecting elements on the surface; simultaneously with forming the interconnection conductor, forming in the test area a test structure having a plurality of closed loops of the electrical conductor having the same linewidth as the interconnection conductor; measuring the impedance or complex reflection coefficient of the test structure using a head disposed opposite the test area, spaced from the surface, and coupled to the test structure without directly contacting the test structure; and correlating the measured impedance or complex reflection coefficient of the test structure with measurements of geometrically identical structures of conductors having known linewidths to determine the linewidth of the test structure and, thereby, the linewidth of the interconnection conductor.
Inventors
- 👤 Robert D. Larrabee
- 👤 Jay F. Marchiando
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 13:44
CPC Classifications
G; G01; G01R; G01R31/00; G01R31/28; G01R31/2851; G01R31/2884; G01R31/302; G01R31/315; H; H10; H10P; H10P74/00; H10P74/20; H10P74/203
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
157 words
A method of measuring the linewidth of an electrical conductor on a semiconductor substrate comprising: preparing mutually separated test and interconnection areas on a surface of a semiconductor substrate; forming an electrical interconnection conductor on the surface of the substrate in the interconnection area having a linewidth and electrically interconnecting elements on the surface; simultaneously with forming the interconnection conductor, forming in the test area a test structure having a plurality of mutually electrically isolated closed loops of the electrical conductor having the same linewidth as the interconnection conductor; measuring the impedance of the test structure using a coil disposed opposite the test area, spaced from the surface, and inductively coupled to the test structure without contacting the test structure; and correlating the measured impedance of the test structure with impedance measurements of geometrically identical structures of conductors having known linewidths to determine the linewidth of the test structure and, thereby, the linewidth of the interconnection conductor.
Claim 2
Independent Claim
157 words
A method of measuring the linewidth of an electrical conductor on a semiconductor substrate comprising: preparing mutually separated test and interconnection areas on a surface of a semiconductor substrate; forming an electrical interconnection conductor on the surface of the substrate in the interconnection area having a linewidth and electrically interconnecting elements on the surface; simultaneously with forming the interconnection conductor, forming in the test area a test structure having a plurality of mutually electrically isolated closed loops of the electrical conductor having the same linewidth as the interconnection conductor; measuring the impedance of the test structure using a coil disposed opposite the test area, spaced from the surface, and inductively coupled to the test structure without contacting the test structure; and correlating the measured impedance of the test structure with impedance measurements of geometrically identical structures of conductors having known linewidths to determine the linewidth of the test structure and, thereby, the linewidth of the interconnection conductor.
Claim 3
Dependent Claim
77 words
The method of claim 1 including preparing a reference area on the surface of the substrate mutually separated from the interconnection area and test area and free of the electrical conductor including, while measuring the impedance of the substrate with the coil opposite the reference area and spaced from the surface, adjusting the spacing between the surface and the coil to obtain a specified measured impedance, thereby establishing a desired spacing between the coil and the surface.
Claim 4
Dependent Claim
43 words
The method of claim 2 including, while maintaining the desired distance between the coil and the surface of the substrate and before measuring the impedance of the test structure, moving the substrate relative to the coil to a position opposite the test structure.
Claim 5
Dependent Claim
20 words
The method of claim 1 including forming a test structure including a plurality of non-intersecting loops having a common center.
Claim 6
Dependent Claim
13 words
The method of claim 4 including forming the loops in a rectangular shape.
Claim 7
Dependent Claim
20 words
The method of claim 1 wherein the coil includes multiple turns connected in series and generally arranged in a plane.
Claim 8
Dependent Claim
56 words
The method of claim 1 including calibrating the linewidth of a test structure by conducting a current through at least part of one of the closed loops between current terminals extending from the loop and measuring the resulting voltage across two voltage terminals extending from the loop and separated from each other by a known distance.
Claim 9
Dependent Claim
18 words
The method of claim 1 including calibrating the linewidth of a test structure by optically measuring the line-width.
Claim 10
Independent Claim
161 words
A method of measuring the linewidth of an electrical conductor on a semiconductor substrate comprising: preparing mutually separated test and interconnection areas on a surface of a semiconductor substrate; forming an electrical interconnection conductor on the surface of the substrate in the interconnection area having a linewidth and electrically interconnecting elements on the surface; simultaneously with forming the interconnection conductor, forming in the test area a test structure having a plurality of closed loops of the electrical conductor having the same linewidth as the interconnection conductor; measuring the complex reflection coefficient of the test structure using a transmission line disposed opposite the test area, spaced from the surface, and electromagnetically coupled to the test structure without contacting the test structure; and correlating the measured complex reflection coefficient of the test structure with complex reflection coefficient measurements of geometrically identical structures of conductors having known linewidths to determine the linewidth of the test structure and, thereby, the linewidth of the interconnection conductor.
Claim 11
Independent Claim
161 words
A method of measuring the linewidth of an electrical conductor on a semiconductor substrate comprising: preparing mutually separated test and interconnection areas on a surface of a semiconductor substrate; forming an electrical interconnection conductor on the surface of the substrate in the interconnection area having a linewidth and electrically interconnecting elements on the surface; simultaneously with forming the interconnection conductor, forming in the test area a test structure having a plurality of closed loops of the electrical conductor having the same linewidth as the interconnection conductor; measuring the complex reflection coefficient of the test structure using a transmission line disposed opposite the test area, spaced from the surface, and electromagnetically coupled to the test structure without contacting the test structure; and correlating the measured complex reflection coefficient of the test structure with complex reflection coefficient measurements of geometrically identical structures of conductors having known linewidths to determine the linewidth of the test structure and, thereby, the linewidth of the interconnection conductor.
Claim 12
Dependent Claim
84 words
The method of claim 9 including preparing a reference area on the surface of the substrate mutually separated from the interconnection area and test area and free of the electrical conductor including, while measuring the complex reflection coefficient of the substrate with the transmission line opposite the reference area and spaced from the surface, adjusting the spacing between the surface and the transmission line to obtain a specified measured complex reflection coefficient, thereby establishing a desired spacing between the transmission line and the surface.
Claim 13
Dependent Claim
47 words
The method of claim 10 including, while maintaining the desired distance between the transmission line and the surface of the substrate and before measuring the complex reflection coefficient of the test structure, moving the substrate relative to the transmission line to a position opposite the test structure.
Claim 14
Dependent Claim
20 words
The method of claim 9 including forming a test structure including a plurality of non-intersecting loops having a common center.
Claim 15
Dependent Claim
13 words
The method of claim 12 including forming the loops in a rectangular shape.
Claim 16
Dependent Claim
56 words
The method of claim 9 including calibrating the linewidth of a test structure by conducting a current through at least part of one of the closed loops between current terminals extending from the loop and measuring the resulting voltage across two voltage terminals extending from the loop and separated from each other by a known distance.
Claim 17
Dependent Claim
19 words
The method of claim 9 including calibrating the linewidth of a test structure by optically measuring the line width.
Claim 18
Dependent Claim
39 words
The method of claim 9 wherein the transmission line is a coaxial cable including forming the test structure to include radially disposed electrically conducting lines parallel to electric field lines produced by a signal propagating in the coaxial cable.
Claim 19
Dependent Claim
35 words
The method of claim 9 wherein the transmission line is a waveguide including forming the test structure to include electrically conducting lines parallel to electric field lines produced by a signal propagating in the waveguide.
References Cited (Backward Citations)
US2291533A
Cited
US3992663A
Cited
US3974443A
Cited
US4074188A
Cited
US4144493A
Cited
US4516071A
Cited
US4833396A
Cited
US4956611A
Cited
US5264377A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-01-15 | 1999-07-17 | 2000-01-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-01-15 | 2003-07-17 | 2004-01-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-01-15 | 2007-07-17 | 2008-01-16 | $7700.00 | Window Closed / Lapsed |