US4910155A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Wafer flood polishing
Assignee: International Business Machines Corp
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Filing: 1988-10-28
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Granted: 1990-03-20
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Expires: 2008-10-28
Abstract
Abstract In a chem-mech polishing process for planarizing insulators such as silicon oxide and silicon nitride, a pool of slurry is utilized at a temperature between 85° F.-95° F. The slurry particulates (e.g. silica) have a hardness commensurate to the hardness of the insulator to be polished. Under these conditions, wafers can be polished at a high degree of uniformity more economically (by increasing pad lifetime), without introducing areas of locally incomplete polishing.
Inventors
- 👤 William J. Cote
- 👤 Michael A. Leach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 06:33
CPC Classifications
H; H10; H10P; H10P95/00; H10P95/06; H10P95/062; B; B24; B24B; B24B37/00; B24B37/005; B24B37/013; B24B37/015; B24B37/04; B24B37/042; B24B49/00; B24B49/16
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
101 words
In a process of chem-mech polishing an insulator layer arranged on a semiconductor wafer, wherein the wafer is brought into contact with a rotating polish wheel having a polishing pad disposed thereon, the improvement comprising: providing sufficient slurry to form a pool defined by a dam disposed about the outer periphery of the polish wheel, wherein said polishing pad is immersed in said pool during polishing, and wherein said slurry comprises a liquid suspension of solid particulates having a hardness commensurate to the hardness of the insulator layer; and elevating the temperature of said slurry to at least approximately 85° F.
Claim 2
Dependent Claim
101 words
In a process of chem-mech polishing an insulator layer arranged on a semiconductor wafer, wherein the wafer is brought into contact with a rotating polish wheel having a polishing pad disposed thereon, the improvement comprising: providing sufficient slurry to form a pool defined by a dam disposed about the outer periphery of the polish wheel, wherein said polishing pad is immersed in said pool during polishing, and wherein said slurry comprises a liquid suspension of solid particulates having a hardness commensurate to the hardness of the insulator layer; and elevating the temperature of said slurry to at least approximately 85° F.
Claim 3
Dependent Claim
19 words
The process as recited in claim 1, wherein said slurry is at a temperature between approximately 85° F.-95° F.
Claim 4
Dependent Claim
20 words
The process as recited in claim 1, wherein said solid particulates have an average size of at least 0.02 microns.
Claim 5
Dependent Claim
19 words
The process is recited in claim 1, wherein said solid particulates constitute approximately 10%-15% by weight of said slurry.
Claim 6
Dependent Claim
16 words
The process as recited in claim 4, wherein said particulates are comprised of SiO 2 .
Claim 7
Dependent Claim
21 words
The process as recited in claim 1, wherein said polish wheel rotates at a speed no greater than approximately 30 RPM.
Claim 8
Dependent Claim
20 words
The process as recited in claim 6, wherein said polish wheel rotates at a speed between approximately 15 RPM-20 RPM.
Claim 9
Dependent Claim
26 words
The process as recited in claim 6, wherein a plurality of semiconductor wafers are simultaneously polished by being brought into contact with the same polish wheel.
Claim 10
Dependent Claim
43 words
The process as recited in claim 8, wherein at least one of said wafers is a dummy wafer comprising a silicon substrate with a discrete layer thereon having a thickness commensurate to the amount of material to be removed from the remaining wafers.
Claim 11
Dependent Claim
23 words
The process as recited in claim 9, further comprising: monitoring said dummy wafer during polishing to indicate when the polishing process is completed.
Claim 12
Dependent Claim
108 words
In a process of chem-mech polishing an insulator layer arranged on a semiconductor wafer, wherein the wafer is brought into contact with a rotating polish wheel having a polishing pad disposed thereon, the improvement comprising: providing sufficient slurry to form a pool defined by a dam disposed about the outer periphery of the polish wheel, wherein said polishing pad is immersed in said pool during polishing, and wherein said slurry comprises a suspension of silica particulates having an average size greater than 0.006 microns, said silica particles comprising approximately 10%-15% by weight of said slurry; and elevating the temperature of said slurry to at least approximately 85° F.
Claim 13
Dependent Claim
108 words
In a process of chem-mech polishing an insulator layer arranged on a semiconductor wafer, wherein the wafer is brought into contact with a rotating polish wheel having a polishing pad disposed thereon, the improvement comprising: providing sufficient slurry to form a pool defined by a dam disposed about the outer periphery of the polish wheel, wherein said polishing pad is immersed in said pool during polishing, and wherein said slurry comprises a suspension of silica particulates having an average size greater than 0.006 microns, said silica particles comprising approximately 10%-15% by weight of said slurry; and elevating the temperature of said slurry to at least approximately 85° F.
Claim 14
Dependent Claim
19 words
The process as recited in claim 11, wherein said silica particulates have an average size of approximately 0.01 microns.
Claim 15
Dependent Claim
21 words
The process as recited in claim 12, wherein said polish wheel rotates at a speed no greater than approximately 30 RPM.
Claim 16
Dependent Claim
20 words
The process as recited in claim 13, wherein said polish wheel rotates at a speed between approximately 15 RPM-20 RPM.
Claim 17
Dependent Claim
26 words
The process as recited in claim 13, wherein a plurality of semiconductor wafers are simultaneously polished by being brought into contact with the same polish wheel.
Claim 18
Dependent Claim
43 words
The method as recited in claim 15, wherein at least one of said wafers is a dummy wafer comprising a silicon substrate with a discrete layer thereon having a thickness commensurate to the amount of material to be removed from the remaining wafers.
Claim 19
Dependent Claim
23 words
The method as recited in claim 16, further comprising: monitoring said dummy wafer during polishing to indicate when the polishing process is completed.
Claim 20
Dependent Claim
125 words
In a process of chem-mech polishing a layer of silicon oxide disposed on a semiconductor substrate, wherein the substrate is supported by a quill in contact with a rotating polish wheel having a polishing pad disposed thereon, the improvement comprising: providing an amount of slurry sufficient to form a pool defined by a dam disposed about the polish wheel, wherein said polishing pad is immersed in said pool during polishing, and wherein said slurry comprises a suspension of approximately 10%-15 % silica particulates by weight, said particulates having an average diameter of at least approximately 0.02 microns; and elevating the temperature of said slurry to at least approximately 85° F.; and wherein said polish wheel rotates at a speed no greater than approximately 30 RPM.
Claim 21
Dependent Claim
125 words
In a process of chem-mech polishing a layer of silicon oxide disposed on a semiconductor substrate, wherein the substrate is supported by a quill in contact with a rotating polish wheel having a polishing pad disposed thereon, the improvement comprising: providing an amount of slurry sufficient to form a pool defined by a dam disposed about the polish wheel, wherein said polishing pad is immersed in said pool during polishing, and wherein said slurry comprises a suspension of approximately 10%-15 % silica particulates by weight, said particulates having an average diameter of at least approximately 0.02 microns; and elevating the temperature of said slurry to at least approximately 85° F.; and wherein said polish wheel rotates at a speed no greater than approximately 30 RPM.
Claim 22
Dependent Claim
33 words
The process as recited in claim 18, wherein said slurry is at a temperature between approximately 85° F. -95° F. and said polish wheel rotates at a speed between approximately 15 RPM-20 RPM.
Claim 23
Dependent Claim
79 words
The process as recited in claim 19, wherein: a plurality of semiconductor wafers are simultaneously polished by being brought into contact with the same polish wheel; and at least one of said wafers is a dummy wafer comprising a silicon substrate with a discrete layer thereon having a thickness commensurate to the amount of material to be removed from the remaining wafers; and further comprising: monitoring said dummy wafer during polishing to indicate when the polishing process is completed.
References Cited (Backward Citations)
US2922264A
Cited
US3436286A
Cited
US3342652A
Cited
US3615955A
Cited
US3841031A
Cited
DD147589A1
Cited
US4256535A
Cited
US4373991A
Cited
US4710264A
Cited
US4671851A
Cited
US4702792A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-03-19 | 1993-09-18 | 1994-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-03-19 | 1997-09-18 | 1998-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-03-19 | 2001-09-18 | 2002-03-20 | $7700.00 | Window Closed / Lapsed |