US4896044A
Expired / Lapsed
US
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Scanning tunneling microscope nanoetching method
Assignee: Purdue Research Foundation
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Filing: 1989-02-17
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Granted: 1990-01-23
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Expires: 2009-02-17
Abstract
Abstract A method is described for forming uniform nanometer sized depressions on the surface of a conducting substrate. A tunneling tip is used to apply tunneling current density sufficient to vaporize a localized area of the substrate surface. The resulting depressions or craters in the substrate surface can be formed in information encoding patterns readable with a scanning tunneling microscope.
Inventors
- 👤 Yun-Zhong Li
- 👤 Ronald G. Reifenberger
- 👤 Ronald P. Andres
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 02:29
CPC Classifications
C; C23; C23F; C23F4/00; C23F4/02; G; G03; G03F; G03F7/00; G03F7/20; G03F7/2049; G11; G11B; G11B9/00; G11B9/12; G11B9/14; G11B9/1463; G11B9/149; B; B82; B82Y; B82Y10/00; B82Y30/00; Y; Y10; Y10S; Y10S977/00; Y10S977/84; Y10S977/849; Y10S977/855; Y10S977/856
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
70 words
A method for creating topographic depressions on a conducting substrate by localized vaporization of the substrate surface on a nanometer scale comprising the steps of: positioning a tunneling tip over said surface so that a tunneling current is detectable in said tunneling tip upon application of a predetermined bias voltage; and transiently increasing the tunneling current to create a power density sufficient to cause localized evaporation of the substrate surface.
Claim 2
Independent Claim
70 words
A method for creating topographic depressions on a conducting substrate by localized vaporization of the substrate surface on a nanometer scale comprising the steps of: positioning a tunneling tip over said surface so that a tunneling current is detectable in said tunneling tip upon application of a predetermined bias voltage; and transiently increasing the tunneling current to create a power density sufficient to cause localized evaporation of the substrate surface.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein the conducting substrate is atomically flat gold.
Claim 4
Dependent Claim
20 words
The method of claim 2 wherein the atomically flat gold has a surficial monolayer of a covalently bound organic compound.
Claim 5
Dependent Claim
22 words
The method of claim 3 wherein the organic compound comprises a C 12 -C 18 carbon chain with a terminal thiol group.
Claim 6
Dependent Claim
20 words
The method of claim 1 wherein the tunneling current is transiently increased by application of a stepped bias voltage pulse.
Claim 7
Independent Claim
70 words
A method for electroetching a gold substrate on a nanometer scale utilizing a scanning tunneling microscope Comprising the steps of: positioning a tunneling tip of the scanning tunneling microscope over the surface of the gold substrate so that a tunnelrng current is detected in said tunneling tip upon application of a predetermined voltage bias; and transiently increasing the tunneling current to about 100 nanoamperes for less than about 500 microseconds.
Claim 8
Independent Claim
70 words
A method for electroetching a gold substrate on a nanometer scale utilizing a scanning tunneling microscope Comprising the steps of: positioning a tunneling tip of the scanning tunneling microscope over the surface of the gold substrate so that a tunnelrng current is detected in said tunneling tip upon application of a predetermined voltage bias; and transiently increasing the tunneling current to about 100 nanoamperes for less than about 500 microseconds.
Claim 9
Dependent Claim
20 words
The method of claim 6 wherein the tunneling current is transiently increased by application of a stepped bias voltage pulse.
Claim 10
Dependent Claim
72 words
A data storage method comprising the steps of: (1) positioning a tunneling tip over a conducting surface so that a tunneling current is detectable in said tunneling tip upon application of a predetermined bias voltage; (2) transiently increasing the tunneling current to create a power density sufficient to cause localized evaporation of the substrate surface; and (3) repeating steps (1) and (2) to create an information encoding pattern in the substrate surface.
Claim 11
Dependent Claim
72 words
A data storage method comprising the steps of: (1) positioning a tunneling tip over a conducting surface so that a tunneling current is detectable in said tunneling tip upon application of a predetermined bias voltage; (2) transiently increasing the tunneling current to create a power density sufficient to cause localized evaporation of the substrate surface; and (3) repeating steps (1) and (2) to create an information encoding pattern in the substrate surface.
Claim 12
Dependent Claim
93 words
A lithographic method utilizing localized vaporization of a resist layer on a conducting surface on a nanometer scale comprising the steps of: treating a substrate surface to form a resist layer comprising a covalently bound monomolecular layer of an organic compound; positioning a tunneling tip over a selected area of said resist layer bearing surface so that a tunneling current is detected in said tunneling tip upon application of a predetermined bias voltage; and transiently increasing the tunneling current to create a power density sufficient to cause localized vaporization of the resist layer.
Claim 13
Dependent Claim
93 words
A lithographic method utilizing localized vaporization of a resist layer on a conducting surface on a nanometer scale comprising the steps of: treating a substrate surface to form a resist layer comprising a covalently bound monomolecular layer of an organic compound; positioning a tunneling tip over a selected area of said resist layer bearing surface so that a tunneling current is detected in said tunneling tip upon application of a predetermined bias voltage; and transiently increasing the tunneling current to create a power density sufficient to cause localized vaporization of the resist layer.
References Cited (Backward Citations)
US4785189A
Cited
US4786922A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-01-22 | 1993-07-24 | 1994-01-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-01-22 | 1997-07-24 | 1998-01-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-01-22 | 2001-07-24 | 2002-01-23 | $7700.00 | Window Closed / Lapsed |