Patent US4513544A successfully refreshed from Google Patents.
US4513544A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of sawing crystalline rods, and multiple-blade internal-hole saw for carrying out the method
Assignee: Siltronic AG
•
Filing: 1983-04-21
•
Granted: 1985-04-30
•
Expires: 2003-04-21
Abstract
Abstract Crystalline rods or blocks can be sawed into thin wafers by sawing the rodr block into a plurality of wafers that are connected to each other. The wafers can be connected by introducing a connecting agent after each sawing step, into the resulting cutting gaps. The wafers are separated only after the whole rod has been sawed. The method makes possible the use of multiple-blade internal-hole saws, and preferably two-blade internal-hole saws.
Inventors
- 👤 Gunter Lossl
- 👤 Helmut Zauhar
- 👤 Horst Stock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 09:42
CPC Classifications
B; B23; B23D; B23D59/00; B23D59/008; B28; B28D; B28D5/00; B28D5/0058; B28D5/02; B28D5/022; B28D5/024; B28D5/028; B28D5/029
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
132 words
A method for sawing a crystalline workpiece into wafers, comprising the steps of: sawing an elongated workpiece of material, by a sequence of cuts, into a plurality of thin wafers that are connected to one another, including the steps of simultaneously making at least two cuts in the workpiece by at least two blades in a manner to produce a plurality of wafers that are connected to each other, each blade separated from another by a distance greater than the thickness of each said wafer, and successively repeating said step of simultaneously making at least two cuts at different locations along said workpiece, one of said at least two successive cuts being between said previous at least two cuts; and breaking the connection between each of the wafers after the sawing operation.
Claim 2
Independent Claim
132 words
A method for sawing a crystalline workpiece into wafers, comprising the steps of: sawing an elongated workpiece of material, by a sequence of cuts, into a plurality of thin wafers that are connected to one another, including the steps of simultaneously making at least two cuts in the workpiece by at least two blades in a manner to produce a plurality of wafers that are connected to each other, each blade separated from another by a distance greater than the thickness of each said wafer, and successively repeating said step of simultaneously making at least two cuts at different locations along said workpiece, one of said at least two successive cuts being between said previous at least two cuts; and breaking the connection between each of the wafers after the sawing operation.
Claim 3
Dependent Claim
56 words
A method according to claim 1, wherein a connection comprising the actual material of the rod or block or a foreign material is retained between the portions of the rod or block and the connection is broken by longitudinal cutting, grinding or loosening to separate the wafers after the entire rod or block has been sawed.
Claim 4
Dependent Claim
28 words
A method according to claim 1, wherein a connecting agent is introduced into the cutting gaps to strengthen the connection between the portions of the rod or block.
Claim 5
Dependent Claim
28 words
A method according to claim 2, wherein a connecting agent is introduced into the cutting gaps to strengthen the connection between the portions of the rod or block.
Claim 6
Dependent Claim
13 words
The method of claim 1 wherein the crystalline rod or block is silicon.
Claim 7
Dependent Claim
36 words
A method according to claim 1, wherein the rods or blocks of material are sawed partially from one end, and after 180° rotation around an axis perpendicular to their longitudinal axis, sawed from their other end.
References Cited (Backward Citations)
SU272883A1
Cited
US3081586A
Cited
US4091580A
Cited
DE2833874A1
Cited
US4150912A
Cited
US4228782A
Cited
US4227348A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-04-29 | 1988-10-29 | 1989-04-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-04-29 | 1992-10-29 | 1993-04-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-04-29 | 1996-10-29 | 1997-04-30 | $7700.00 | Window Closed / Lapsed |