← Back to Patent Explorer
US3982271A Expired / Lapsed US ⏱️ 0.0 years remaining

Heat spreader and low parasitic transistor mounting

Assignee: RCA Corp
•
Filing: 1975-02-07
•
Granted: 1976-09-21
•
Expires: 1995-02-07
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract An apparatus for heat spreading and low parasitic transistor mounting in high power microstrip circuit applications. An electrically and thermally conductive strip is conductively affixed to the ground plane of a substrate containing the circuit. The strip is shaped to fit substantially within a slot in a circuit carrier block (heat sink) such that the strip makes intimate contact between the mounting surface of the transistor mounted in the slot and the carrier block. The strip provides the electrical connection between the ground plane of the substrate and the carrier block in addition to increasing the surface area for more efficient heat transfer, and thus, allows for the ground plane of the substrate to be attached to the block either by a non-metallic adhesive or by solder.

Inventors

  • 👤 Daniel Olivieri
  • 👤 Robert James Socci

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-24 14:56
CPC Classifications
H; H05; H05K; H05K1/00; H05K1/02; H05K1/0201; H05K1/0203; H05K1/021; H10; H10W; H10W40/00; H10W40/10; H10W40/20; H10W40/25; H10W40/258; H10W40/60; H10W40/611; H10W44/00; H10W44/20; H10W78/00; H05K1/0213; H05K1/0237; H05K1/18; H05K1/182; H05K2201/00; H05K2201/09; H05K2201/09209; H05K2201/09654; H05K2201/09745; H05K2201/10; H05K2201/10007; H05K2201/10166; H05K2201/10227; H05K2201/10409; H05K3/00; H05K3/0058; H05K3/0061; H10W40/231; H10W40/235

Claims Analysis

Total Claims: 8
Claim 1
Independent Claim 182 words
In a transistor mounting apparatus of the type used in high power microstrip circuits including a transistor wherein said transistor is mounted in a slot formed in a circuit carrier block formed of electrically and thermally conductive material serving as a heat sink and electric ground, further including a non-conductive substrate having on one face a strip line conductor and on the other face a conductive ground plane, said ground plane being positioned to be mounted on said circuit carrier block, said substrate, including said strip line conductor and said ground plane arranged to receive said transistor, and further including electrically conductive connections between said transistor and said strip line conductor, the improvement comprising: a strip of thin, soft, deformably, electrically and thermally conductive material, said strip being positioned in said slot and clamped against the bottom wall of said slot by said transistor, the respective ends of said strip being joined with an electrical and thermal connection to said ground plane at respective opposite portions thereof adjacent said slot, said ground plane including said strip ends being affixed to said block.
Claim 2
Dependent Claim 182 words
In a transistor mounting apparatus of the type used in high power microstrip circuits including a transistor wherein said transistor is mounted in a slot formed in a circuit carrier block formed of electrically and thermally conductive material serving as a heat sink and electric ground, further including a non-conductive substrate having on one face a strip line conductor and on the other face a conductive ground plane, said ground plane being positioned to be mounted on said circuit carrier block, said substrate, including said strip line conductor and said ground plane arranged to receive said transistor, and further including electrically conductive connections between said transistor and said strip line conductor, the improvement comprising: a strip of thin, soft, deformably, electrically and thermally conductive material, said strip being positioned in said slot and clamped against the bottom wall of said slot by said transistor, the respective ends of said strip being joined with an electrical and thermal connection to said ground plane at respective opposite portions thereof adjacent said slot, said ground plane including said strip ends being affixed to said block.
Claim 3
Dependent Claim 16 words
An apparatus according to claim 1, wherein said strip is gold-plated, soft, high thermal conductivity copper.
Claim 4
Dependent Claim 18 words
An apparatus according to claim 1, wherein said strip is joined to said ground plane by a fusion-bond.
Claim 5
Dependent Claim 17 words
An apparatus according to claim 1, wherein said strip is connected to said transistor by a fusion-bond.
Claim 6
Dependent Claim 15 words
An apparatus according to claim 1, wherein said strip is wider than said strip line.
Claim 7
Dependent Claim 19 words
An apparatus according to claim 1, wherein said ground plane is affixed to said block by a non-metallic adhesive.
Claim 8
Dependent Claim 19 words
An apparatus according to claim 1, wherein said ground plane is affixed to said block by a metallic solder.

References Cited (Backward Citations)

US3686457A Cited
US3823351A Cited
US3913040A Cited
US3908188A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1979-09-21 1980-03-22 1980-09-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1983-09-21 1984-03-22 1984-09-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1987-09-21 1988-03-22 1988-09-21 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag