Patent US5348615A successfully refreshed from Google Patents.
US5348615A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Selective planarization method using regelation
Assignee: GlobalFoundries Inc
•
Filing: 1993-09-10
•
Granted: 1994-09-20
•
Expires: 2013-09-10
Abstract
Abstract Technique and apparatus for planarizing microsteps on a substrate by compressing the surface to be smoothed against a frozen layer of an etchant, where the compressive force is sufficient to melt the etchant at the contact edges between said microsteps and said etchant.
Inventors
- 👤 Subhash Gupta
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:36
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/04; B; B24; B24B; B24B37/00; B24B37/04; B24B37/042; H10P72/00; H10P72/04; H10P72/0402; H10P72/0418; H10P72/0422; H10P95/06; H10P95/062; H10P95/064; H10P95/066
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
147 words
A method for smoothing a selected surface area of a substrate comprising the steps of, selecting a material which is a liquid at room temperatures and which will etch said substrate; creating a frozen layer of said selected material, said frozen layer having a surface which is smooth over an area larger than said area of said selected surface of said substrate; causing a portion of the surface of said substrate to come into contact with said frozen layer; applying a compressive force to squeeze said portion of said selected surface of said substrate against the surface of said frozen layer; causing said compressive force to be at least the amount of force for the temperature and pressure of said frozen layer which causes melting of said frozen layer in those regions where protruding points or edges on said substrate come into contact with said frozen layer.
Claim 2
Independent Claim
147 words
A method for smoothing a selected surface area of a substrate comprising the steps of, selecting a material which is a liquid at room temperatures and which will etch said substrate; creating a frozen layer of said selected material, said frozen layer having a surface which is smooth over an area larger than said area of said selected surface of said substrate; causing a portion of the surface of said substrate to come into contact with said frozen layer; applying a compressive force to squeeze said portion of said selected surface of said substrate against the surface of said frozen layer; causing said compressive force to be at least the amount of force for the temperature and pressure of said frozen layer which causes melting of said frozen layer in those regions where protruding points or edges on said substrate come into contact with said frozen layer.
Claim 3
Dependent Claim
36 words
The method of claim 1 wherein relative motion is caused to take place between said substrate and said layer of said frozen etchant material while maintaining said compressive contact between said frozen layer and said substrate.
Claim 4
Dependent Claim
36 words
The method of claim 2 wherein the step of applying compressive force is accomplished by enclosing said substrate and said layer of said layer in a sealable chamber and increasing the pressure in said sealable chamber.
Claim 5
Dependent Claim
34 words
The method of claim 3 wherein said relative movement is carried out by a slow relative movement of said substrate with respect to said layer of said frozen etchant material along a rotational path.
Claim 6
Independent Claim
176 words
A method for smoothing a selected surface of a substrate having protruding micropoints or edges comprising the steps of, selecting a material which is a liquid at a first temperature and which will etch said substrate when said material is in said liquid state; creating a frozen layer of said selected material, said frozen layer having a surface area which is smooth over an area which is larger than said selected surface of said substrate; applying a portion of the surface of said substrate into contact with said frozen layer; applying a compressive force between said portion of the surface of said substrate and the surface of said frozen layer such that the surface of said frozen layer and said portion of the surface of said substrate are compressed together; causing said compressive force to be at least theamount of force for the temperature and pressure of said frozen layer which causes melting of said frozen layer in those regions where said portion of the surface of said substrate come into contact with said frozen layer.
Claim 7
Independent Claim
176 words
A method for smoothing a selected surface of a substrate having protruding micropoints or edges comprising the steps of, selecting a material which is a liquid at a first temperature and which will etch said substrate when said material is in said liquid state; creating a frozen layer of said selected material, said frozen layer having a surface area which is smooth over an area which is larger than said selected surface of said substrate; applying a portion of the surface of said substrate into contact with said frozen layer; applying a compressive force between said portion of the surface of said substrate and the surface of said frozen layer such that the surface of said frozen layer and said portion of the surface of said substrate are compressed together; causing said compressive force to be at least theamount of force for the temperature and pressure of said frozen layer which causes melting of said frozen layer in those regions where said portion of the surface of said substrate come into contact with said frozen layer.
Claim 8
Dependent Claim
80 words
The method of claim 5 wherein said portion of said substrate which is in contact with said frozen layer when melting occurs has a total contact area A 1 and wherein said compressive force is F 1 and wherein refreezing of said melted portions of said frozen layer occurs under said micropoints if the pressure under said micropoints on said frozen layer surface is less than P 1 , where P 1 is equal to F 1 /A 1 .
Claim 9
Dependent Claim
30 words
The method of claim 6 wherein said step of applying a compressive force includes establishing an operating point which is slightly in the solid region of the liquid-solid phase locus.
Claim 10
Dependent Claim
45 words
The method of claim 5 further includes the step of, inducing relative motion between said portion of the surface of said substrate and said surface of said frozen layer at the same time that said step of applying a compressive force is being carried out.
Claim 11
Dependent Claim
12 words
The method of claim 8 wherein said induced relative motion is random.
Claim 12
Dependent Claim
12 words
The method of claim 8 wherein said induced relative motion is circular.
Claim 13
Dependent Claim
41 words
The method of claim 5 wherein said step of applying a compressive force comprises, applying an adjustable pressure in a chamber containing said substrate and said frozen layer by providing a pressurized gas to compress said substrate into said frozen layer.
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) | 1997-09-19 | 1998-03-21 | 1998-09-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2001-09-19 | 2002-03-21 | 2002-09-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2005-09-19 | 2006-03-21 | 2006-09-20 | $7700.00 | Window Closed / Lapsed |