Patent US4161740A successfully refreshed from Google Patents.
US4161740A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High frequency power transistor having reduced interconnection inductance and thermal resistance
Assignee: STMicroelectronics lnc USA
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Filing: 1977-11-07
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Granted: 1979-07-17
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Expires: 1997-11-07
Abstract
Abstract A transistor having small, closely spaced emitter and base contact areas and an active area capable of generating heat to be removed, is provided with an electrode structure comprising a finger electrode for connecting emitter or base contact areas with one or more bonding pads beside the active area and, electrically insulated from the finger electrode, a bonding plate electrode overlaying at least a portion of the active area for electrically contacting the base or emitter contact areas, respectively. This contact structure has reduced interconnection inductance and resistance, reduced MOS capacitance, and reduced thermal resistance. In addition, it provides a structure which is suitable for both conventional and flip chip mounting.
Inventors
- 👤 Richard H. Frey
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 23:41
CPC Classifications
H; H10; H10W; H10W20/00; H10W20/40; H10W20/482; H10W20/484; H10W44/00; H10W44/20; H10W72/00; H10W72/071; H10W72/072; H10W72/07231; H10W72/07236; H10W72/07251; H10W72/20; H10W72/50; H10W72/541; H10W72/5445
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
155 words
In a microwave power transistor of the type comprising a base pocket active area capable of generating heat to be removed, a plurality of spaced emitter rows within the boundaries of said base pocket and a plurality of discrete base areas closely spaced between successive spaced emitter rows, an improved electrical contact structure comprising: bonding pad means on two sides of said base pocket active area; a finger electrode structure for making electrical contact with said discrete base areas, said fingers extending across said base pocket active area for making electrical contact with said bonding pad means; an insulating layer overlying said finger electrode structure in the region overlying said base pocket active area; and emitter bonding plate means for making electrical contact with said emitter rows, said emitter bonding plate means overlying at least a portion of said base pocket active area and being insulated from said finger electrode structure by said insulating layer.
Claim 2
Dependent Claim
155 words
In a microwave power transistor of the type comprising a base pocket active area capable of generating heat to be removed, a plurality of spaced emitter rows within the boundaries of said base pocket and a plurality of discrete base areas closely spaced between successive spaced emitter rows, an improved electrical contact structure comprising: bonding pad means on two sides of said base pocket active area; a finger electrode structure for making electrical contact with said discrete base areas, said fingers extending across said base pocket active area for making electrical contact with said bonding pad means; an insulating layer overlying said finger electrode structure in the region overlying said base pocket active area; and emitter bonding plate means for making electrical contact with said emitter rows, said emitter bonding plate means overlying at least a portion of said base pocket active area and being insulated from said finger electrode structure by said insulating layer.
Claim 3
Dependent Claim
27 words
A transistor according to claim 1 wherein each of said emitter rows comprises a plurality of emitter sites connected together by a contact strip of conductive material.
Claim 4
Dependent Claim
19 words
A transistor according to claim 1 wherein said emitter bonding plate means overlies substantially all of said active area.
Claim 5
Dependent Claim
200 words
A high frequency power transistor comprising: a collector layer of a first type of semiconductor material; a base pocket layer of opposite type of semiconductor material overlaying said collector layer and defining therewith a base-collector junction; a plurality of rows of spaced emitter areas of said first type of semiconductor material extending into said base pocket layer to form base-emitter junctions around the peripheries of said emitter areas; a first insulating layer overlying said base layer; a plurality of openings extending through said first insulating layer to said emitter areas; a plurality of openings extending through said first insulating layer to a plurality of discrete portions of said base pocket layer; conductive base contact means connecting said plurality of discrete portions of said base pocket layer to enlarged contact regions on one or more sides of said base pocket; a second insulating layer overlying said conductive base contact means in the region overlying said base pocket layer; and conductive emitter contact means overlying and contacting said emitter areas and overlying said second insulating layer in regions overlying said conductive base contact means, said conductive emitter contact means being insulated from said conductive base contact means by said second insulating layer.
Claim 6
Dependent Claim
200 words
A high frequency power transistor comprising: a collector layer of a first type of semiconductor material; a base pocket layer of opposite type of semiconductor material overlaying said collector layer and defining therewith a base-collector junction; a plurality of rows of spaced emitter areas of said first type of semiconductor material extending into said base pocket layer to form base-emitter junctions around the peripheries of said emitter areas; a first insulating layer overlying said base layer; a plurality of openings extending through said first insulating layer to said emitter areas; a plurality of openings extending through said first insulating layer to a plurality of discrete portions of said base pocket layer; conductive base contact means connecting said plurality of discrete portions of said base pocket layer to enlarged contact regions on one or more sides of said base pocket; a second insulating layer overlying said conductive base contact means in the region overlying said base pocket layer; and conductive emitter contact means overlying and contacting said emitter areas and overlying said second insulating layer in regions overlying said conductive base contact means, said conductive emitter contact means being insulated from said conductive base contact means by said second insulating layer.
References Cited (Backward Citations)
US4024568A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-07-16 | 1983-01-15 | 1983-07-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-07-16 | 1987-01-15 | 1987-07-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-07-16 | 1991-01-15 | 1991-07-17 | $7700.00 | Window Closed / Lapsed |