US4084354A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process for slicing boules of single crystal material
Assignee: International Business Machines Corp
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Filing: 1977-06-03
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Granted: 1978-04-18
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Expires: 1997-06-03
Abstract
Abstract A process for slicing boules of a single crystal material such as gadolinium gallium garnet (GGG) into wafers is described. The boule is prepared, by grinding preferably, so that the longitudinal boule axis corresponds to the crystallographic orientation axis of the boule. The boule is then mounted in a fixture and aligned so that the common longitudinal axis and crystallographic orientation axis is perpendicular to the saw blade. The boule is then rotated while maintaining the orientation of the combined common axis and engaged against an inner diameter rotating saw blade for a time sufficient for the blade to slice through the boule and form a wafer. The wafers obtained by this slicing process may be directly polished without the conventional lapping step to form a wafer having a surface that is substantially flat, parallel and defect free.
Inventors
- 👤 Johannes Grandia
- 👤 John Charles Hill
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:46
CPC Classifications
B; B28; B28D; B28D5/00; B28D5/02; B28D5/022; B28D5/028; B28D1/00; B28D1/003; C; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/28; C30B33/00
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
85 words
A method of slicing a boule of a hard single crystal material comprising the steps of treating the surface of said boule to provide said boule with a longitudinal axis that is substantially the same as the crystallographic axis, positioning said treated boule to have an orientation substantially perpendicular to an inner diameter rotatable saw blade, rotating said boule about said longitudinal axis while maintaining said orientation, and engaging said rotating boule against said rotating saw blade whereby a wafer is sliced from said boule.
Claim 2
Independent Claim
85 words
A method of slicing a boule of a hard single crystal material comprising the steps of treating the surface of said boule to provide said boule with a longitudinal axis that is substantially the same as the crystallographic axis, positioning said treated boule to have an orientation substantially perpendicular to an inner diameter rotatable saw blade, rotating said boule about said longitudinal axis while maintaining said orientation, and engaging said rotating boule against said rotating saw blade whereby a wafer is sliced from said boule.
Claim 3
Dependent Claim
25 words
A method as described in claim 1 whereby the boule surface is treated so that the longitudinal axis is within 0.1° of the crystallographic axis.
Claim 4
Dependent Claim
25 words
A method as described in claim 1 whereby the boule surface is treated so that the longitudinal axis is within 0.05° of the crystallographic axis.
Claim 5
Dependent Claim
26 words
A method as described in claim 1 whereby the boule is rotated at between 10 to 100 rpm without vibrations that adversely affect the wafer surface.
Claim 6
Dependent Claim
18 words
A method as described in claim 4 whereby the boule is rotated at between 10 to 45 rpm.
Claim 7
Dependent Claim
19 words
A method as described in claim 1 whereby the boule and the saw blade rotate in the same direction.
Claim 8
Dependent Claim
18 words
A method as described in claim 1 whereby the boule and the saw blade rotate in opposite directions.
Claim 9
Independent Claim
102 words
A method of slicing a boule of a hard single crystal material comprising the steps of treating the surface of said boule to provide said boule with a longitudinal axis that is substantially the same as the crystallographic axis, positioning said treated boule to have an orientation substantially perpendicular to an inner diameter rotatable saw blade, rotating said boule about said longitudinal axis while maintaining said orientation, engaging said rotating boule against said rotating saw blade whereby a wafer is sliced from said boule, and polishing said wafer for a time sufficient to provide a smooth surface that is flat and parallel.
Claim 10
Independent Claim
102 words
A method of slicing a boule of a hard single crystal material comprising the steps of treating the surface of said boule to provide said boule with a longitudinal axis that is substantially the same as the crystallographic axis, positioning said treated boule to have an orientation substantially perpendicular to an inner diameter rotatable saw blade, rotating said boule about said longitudinal axis while maintaining said orientation, engaging said rotating boule against said rotating saw blade whereby a wafer is sliced from said boule, and polishing said wafer for a time sufficient to provide a smooth surface that is flat and parallel.
Claim 11
Dependent Claim
18 words
A method as described in claim 8 including the step of polishing the wafer on the second surface.
Claim 12
Dependent Claim
20 words
A method as described in claim 9 including the step of lapping one surface of the wafer prior to polishing.
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) | 1981-04-17 | 1981-10-17 | 1982-04-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-04-17 | 1985-10-17 | 1986-04-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-04-17 | 1989-10-17 | 1990-04-18 | $7700.00 | Window Closed / Lapsed |