US3722080A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for producing the base of a semiconductor device
Assignee: Individual
•
Filing: 1971-11-12
•
Granted: 1973-03-27
•
Expires: 1991-11-12
Abstract
Abstract In a method for producing the base of a semiconductor device from a composite metal workpiece comprising a lower metal layer possessing high electric and thermal conductivities and an upper metal layer clad on the lower metal layer and possessing high electric resistance suitable for electric resistance welding, a semiconductor pellet or element mounting raised portion formed in the workpiece as the workpiece is deformed to a predetermined final base shape is removed the upper metal layer therefrom so as to expose the lower metal layer on the upper surface of the raised portion whereby the exposed metal layer is ready for directly mounting a semiconductor pellet thereon. Alternatively, the workpiece is deformed so as to elongate the upper metal layer in the raised portion to reduce its thickness whereby the surface of the thinned metal layer is ready for mounting a semiconductor pellet thereon.
Inventors
- 👤 Y Sato
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:50
CPC Classifications
H; H10; H10W; H10W99/00; Y; Y10; Y10S; Y10S72/00; Y10S72/70; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49204; Y10T29/49208; Y10T29/49218
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
197 words
A method for producing the base of a semiconductor device which comprises a first area including a raised area where a semi-conductor pellet is to be mounted and a second area where the flange of a cap shell adapted to enclose said semiconductor pellet is to be secured by electric resistance welding, said method comprising the steps of preparing a clad or composite metal including a first or lower metal layer possessing high electric and thermal conductivities and a second or upper metal layer clad on said first metal layer and suitable for electric resistance welding; preparing workpieces by punching said composite metal to a predetermined size; deforming each of said workpiece to a predetermined final base shape so as to protrude the workpiece in the center thereof toward said second metal layer thereby to form a raised portion which provides said first area and said second area in the remaining sur-face region surrounding said raised portion; exposing said first metal layer on the upper surface of said raised portion by cutting off portion of said raised portion in horizon whereby the upper surface of said exposed metal layer is ready for mounting said semiconductor pellet thereon.
Claim 2
Independent Claim
197 words
A method for producing the base of a semiconductor device which comprises a first area including a raised area where a semi-conductor pellet is to be mounted and a second area where the flange of a cap shell adapted to enclose said semiconductor pellet is to be secured by electric resistance welding, said method comprising the steps of preparing a clad or composite metal including a first or lower metal layer possessing high electric and thermal conductivities and a second or upper metal layer clad on said first metal layer and suitable for electric resistance welding; preparing workpieces by punching said composite metal to a predetermined size; deforming each of said workpiece to a predetermined final base shape so as to protrude the workpiece in the center thereof toward said second metal layer thereby to form a raised portion which provides said first area and said second area in the remaining sur-face region surrounding said raised portion; exposing said first metal layer on the upper surface of said raised portion by cutting off portion of said raised portion in horizon whereby the upper surface of said exposed metal layer is ready for mounting said semiconductor pellet thereon.
Claim 3
Dependent Claim
50 words
The method for producing the base of a semiconductor device as set forth in claim 1, in which during said deforming step an annular recess is formed in the surface of said workpiece surrounding said raised portion whereby said second metal layer is prevented from intruding into the raised portion.
Claim 4
Independent Claim
196 words
The method for producing the base of a semiconductor device which comprises a first area including a raised portion where a semi-conductor pellet is to be mounted and a second area where the flange of a cap shell adapted to enclose said semiconductor pellet is to be secured by electric resistance welding, said method comprising the steps of preparing a composite metal including a first or lower metal layer possessing high electric and thermal conductivities and a second or upper metal layer clad on said first metal layer and suitable for electric resistance welding; preparing workpieces by punching said composite metal to a predetermined size; deforming each of said workpieces to a predetermined final base shape so as to protrude the workpiece in the center thereof toward said second metal layer to elongate the metal layer to reduce its thickness and at the same time to form a raised portion in the surface of the workpiece as said first area and also said second area in the remaining surface region of the workpiece surrounding the raised portion whereby the surface of said second area is ready for mounting said semiconductor pellet thereon by electric resistance welding.
Claim 5
Independent Claim
196 words
The method for producing the base of a semiconductor device which comprises a first area including a raised portion where a semi-conductor pellet is to be mounted and a second area where the flange of a cap shell adapted to enclose said semiconductor pellet is to be secured by electric resistance welding, said method comprising the steps of preparing a composite metal including a first or lower metal layer possessing high electric and thermal conductivities and a second or upper metal layer clad on said first metal layer and suitable for electric resistance welding; preparing workpieces by punching said composite metal to a predetermined size; deforming each of said workpieces to a predetermined final base shape so as to protrude the workpiece in the center thereof toward said second metal layer to elongate the metal layer to reduce its thickness and at the same time to form a raised portion in the surface of the workpiece as said first area and also said second area in the remaining surface region of the workpiece surrounding the raised portion whereby the surface of said second area is ready for mounting said semiconductor pellet thereon by electric resistance welding.
Claim 6
Dependent Claim
55 words
The method for preparing the base of a semiconductor device as set forth in claim 3, in which during said deforming step an annular recess is formed in the surface of said workpiece surrounding said raised portion whereby said second or upper metal layer of the workpiece is prevented from intruding into said raised portion.
References Cited (Backward Citations)
US3197843A
Cited
US3348297A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-03-26 | 1976-09-25 | 1977-03-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-03-26 | 1980-09-25 | 1981-03-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-03-26 | 1984-09-25 | 1985-03-27 | $7700.00 | Window Closed / Lapsed |