US3921884A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Beam lead tool
Assignee: CALX Inc
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Filing: 1973-09-28
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Granted: 1975-11-25
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Expires: 1993-09-28
Abstract
Abstract The beam lead tool is for picking up and bonding semi-conductor wafers or dice to a substrate and includes an accommodating recess in which the wafer is positioned and a suction duct for permitting the wafer to be retained in the tool. The tool is formed as a tip at one end having a peripheral beam lead contacting surface that is formed by a grinding and lapping process wherein a radius or other curvature is defined along the inner facing edges defined by the contacting surface. The surface is first ground to a flatness and is then lapped by a vibratory motion against a resilient stationary pad such as a chamois impregnated with an abrasive material such as a conventional diamond paste.
Inventors
- 👤 Thomas L Mcdonough
- 👤 Martin M Mcdonough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 15:35
CPC Classifications
H; H10; H10P; H10P72/00; H10P72/04; H10P72/0446
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
137 words
A tool for positioning and bonding a beam lead semiconductor wafer comprising; an upper portion adapted to be connected to a holder, and a lower portion terminating in a tip, said lower portion having means defining a peripheral wall having a lower contacting surface and forming a recess in the tip for accommodating the semiconductor wafer, said wall defining an arcuate inner edge, said peripheral wall beind defined at least in part by an inner wall surface defining the recess, said inner edge approximating a curvature of greater than 0.3 mils and formed to assymptotically approach said inner wall surface and said lower contacting surface, wherein the form of the inner edge is controlled by the equation c (f) PK where p applied pressure, c curvature of arcuate inner edge and K thickness of nap of chamois.
Claim 2
Dependent Claim
137 words
A tool for positioning and bonding a beam lead semiconductor wafer comprising; an upper portion adapted to be connected to a holder, and a lower portion terminating in a tip, said lower portion having means defining a peripheral wall having a lower contacting surface and forming a recess in the tip for accommodating the semiconductor wafer, said wall defining an arcuate inner edge, said peripheral wall beind defined at least in part by an inner wall surface defining the recess, said inner edge approximating a curvature of greater than 0.3 mils and formed to assymptotically approach said inner wall surface and said lower contacting surface, wherein the form of the inner edge is controlled by the equation c (f) PK where p applied pressure, c curvature of arcuate inner edge and K thickness of nap of chamois.
Claim 3
Dependent Claim
52 words
The tool of claim 1 wherein said arcuate inner edge has at least two segments, an inner segment that approximates a straight line segment at a small angle to said inner wall surface, and an outer segment that approximates a straight line segment at a small angle to said lower contacting surface.
Claim 4
Dependent Claim
18 words
The tool of claim 2 wherein said outer segment is at approximately 1*-15* to said lower contacting surface.
Claim 5
Dependent Claim
64 words
The tool of claim 3 wherein said inner and outer segments are joined at a point, the distance, in the direction of said inner wall surface, from said point to said lower contacting surface being less than the distance, in the direction of said lower contacting surface, from said inner wall surface to a spot where said outer segment joins said lower contacting surface.
Claim 6
Dependent Claim
52 words
The tool of claim 4 wherein the distance, in the direction of said inner wall surface, from said point to a spot where said inner segment joins said inner wall surface is greater than the distance, in the direction of said inner wall surface, from said point to said lower contacting surface.
Claim 7
Dependent Claim
40 words
The tool of claim 5 wherein the distance in the direction of said inner wall surface from said lower contacting surface to a spot where said inner segment joins said inner wall surface is on the order of 5 mils.
Claim 8
Dependent Claim
66 words
The tool of claim 6 wherein the distance in the direction of said inner wall surface from said Point to said lower contacting surface is on the order of 1 mil and the distance in the direction of said lower contacting surface from said inner wall surface to a spot where said outer segment joins said lower contacting surface is on the order of 5 mils.
Claim 9
Dependent Claim
25 words
The tool of claim 1 wherein said inner edge is hyperbolic in shape and governed by the equation XY constant where the constant is small.
Claim 10
Dependent Claim
12 words
The tool of claim 8 wherein the constant is less than one.
Claim 11
Dependent Claim
21 words
The tool of claim 1 wherein said peripheral wall also defines an outer edge that is sharper than said inner edge.
Claim 12
Dependent Claim
10 words
The tool of claim 1 wherein said curvature is hyperbolic.
Claim 13
Dependent Claim
15 words
The tool of claim 1 wherein said curvature is on the order of 1 mil.
Claim 14
Dependent Claim
134 words
A tool for positioning and bonding a beam lead device comprising; an upper portion adapted to be connected to a holder, and a lower portion terminating in a tip, said lower portion having means defining a peripheral wall having a lower contacting surface and forming a recess in the tip for accommodating the device, said wall defining an arcuate inner edge, said peripheral wall being defined at least in part by an inner wall surface forming the recess, said inner edge approximating a curvature of greater than 0.3 mils and formed to assymptotically approach said inner wall surface and said lower contacting surface, wherein the form of the inner edge is controlled by the equation: c PK where P applied pressure, c curvature of arcuate inner edge, and K thickness of nap of chamois.
Claim 15
Dependent Claim
134 words
A tool for positioning and bonding a beam lead device comprising; an upper portion adapted to be connected to a holder, and a lower portion terminating in a tip, said lower portion having means defining a peripheral wall having a lower contacting surface and forming a recess in the tip for accommodating the device, said wall defining an arcuate inner edge, said peripheral wall being defined at least in part by an inner wall surface forming the recess, said inner edge approximating a curvature of greater than 0.3 mils and formed to assymptotically approach said inner wall surface and said lower contacting surface, wherein the form of the inner edge is controlled by the equation: c PK where P applied pressure, c curvature of arcuate inner edge, and K thickness of nap of chamois.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-11-24 | 1979-05-26 | 1979-11-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-11-24 | 1983-05-26 | 1983-11-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-11-24 | 1987-05-26 | 1987-11-25 | $7700.00 | Window Closed / Lapsed |