US4549197A
Expired / Lapsed
US
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Common-gate GaAs FET design for monolithic microwave integrated circuits
Assignee: Texas Instruments Inc
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Filing: 1982-07-06
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Granted: 1985-10-22
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Expires: 2002-07-06
Abstract
Abstract In order to provide low and exactly repeatable common lead inductance (gate lead inductance) and low feedback parasitics in a common-gate low noise amplifier, a GaAs FET connects the gate electrode to ground at various points along its width by means of an air bridge crossover structure. This structure crosses over the input (source) lines with very low capacitance. Since the gate lead inductance is low in this design, and because in monolithic form this inductance does not vary as is the case for a device grounded using bond wires, common-gate circuit stability is assured. This device preferably uses the well-known pi-gate configuration to provide low drain-gate parasitic capacitance and equal phasing to all parts of the device.
Inventors
- 👤 Gailon E. Brehm
- 👤 Randall E. Lehmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 01:18
CPC Classifications
H; H03; H03F; H03F3/00; H03F3/60; H03F3/601; H03F3/189; H03F3/19; H03F3/193; H03F2200/00; H03F2200/372
Claims Analysis
Total Claims: 19
Claim 1
Independent Claim
160 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one half microns and a greater dimension which is more than 100 microns; a plurality of source regions, said source regions being positioned parallel, adjacent to, and separated from said gate, all of said plurality of source regions being commonly fed; a drain region, said drain region being parallel, adjacent to, and separated from said gate, said source and drain regions lying on opposite sides of said gate; said plurality of source regions being fed by respective source feed, all of said source feeds being connected together in common; a gate pad, said gate pad being connected to said gate and being positioned within the area defined by said plurality of source feeds; a ground contact; and an air bridge connecting said gate pad over at least one of said source feeds to said ground contact.
Claim 2
Dependent Claim
160 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one half microns and a greater dimension which is more than 100 microns; a plurality of source regions, said source regions being positioned parallel, adjacent to, and separated from said gate, all of said plurality of source regions being commonly fed; a drain region, said drain region being parallel, adjacent to, and separated from said gate, said source and drain regions lying on opposite sides of said gate; said plurality of source regions being fed by respective source feed, all of said source feeds being connected together in common; a gate pad, said gate pad being connected to said gate and being positioned within the area defined by said plurality of source feeds; a ground contact; and an air bridge connecting said gate pad over at least one of said source feeds to said ground contact.
Claim 3
Dependent Claim
160 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one half microns and a greater dimension which is more than 100 microns; a plurality of drain regions, said drain regions being positioned parallel, adjacent to, and separated from said gate, all of said plurality of drain regions being commonly fed; a source region, said source region being parallel, adjacent to, and separated from said gate, said drain and source regions lying on opposite sides of said gate; said plurality of drain regions being fed by respective drain feeds, all of said drain feeds being connected together in common; a gate pad, said gate pad being connected to said gate and being positioned within the area defined by said plurality of drain feeds; a ground contact; and an air bridge connecting said gate pad over at least one of said drain feeds to said ground contact.
Claim 4
Dependent Claim
160 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one half microns and a greater dimension which is more than 100 microns; a plurality of drain regions, said drain regions being positioned parallel, adjacent to, and separated from said gate, all of said plurality of drain regions being commonly fed; a source region, said source region being parallel, adjacent to, and separated from said gate, said drain and source regions lying on opposite sides of said gate; said plurality of drain regions being fed by respective drain feeds, all of said drain feeds being connected together in common; a gate pad, said gate pad being connected to said gate and being positioned within the area defined by said plurality of drain feeds; a ground contact; and an air bridge connecting said gate pad over at least one of said drain feeds to said ground contact.
Claim 5
Dependent Claim
30 words
The device of claim 1 or 2, further comprising additional contacts to said gate near the ends of said gate, said additional contacts also being connected to said ground contact.
Claim 6
Dependent Claim
30 words
The device of claim 1, wherein said drain is connected by multiple separate leads to a drain feed, said multiple separate leads being spaced along the length of said drain.
Claim 7
Dependent Claim
30 words
The device of claim 2, wherein said source is connected by multiple separate leads to a source feed, said multiple separate leads being spaced along the length of said source.
Claim 8
Dependent Claim
17 words
The device of claim 1, 2, 4, or 5, wherein said gate lies on a semiconducting substrate.
Claim 9
Dependent Claim
12 words
The device of claim 6, wherein said semiconducting substrate is gallium arsenide.
Claim 10
Dependent Claim
172 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one-half microns and a greater dimension which is more than 100 microns; a plurality of source regions, said source regions being positioned parallel, adjacent to, and separated from one side of said gate stripe, all of said plurality of source regions being commonly fed; a drain region, said drain region being parallel, adjacent to, and separated from said gate, said source and drain regions lying on opposite sides of said gate; said plurality of source regions being fed by respective source feeds, all of said source feeds being connected together in common; a gate pad, said gate pad being connected to said gate stripe and being positioned within the area defined by said plurality of source feeds adjacent to one side of said gate stripe; a ground contact; and an air bridge connecting said gate pad over at least one of said source feeds to said ground contact.
Claim 11
Dependent Claim
172 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one-half microns and a greater dimension which is more than 100 microns; a plurality of source regions, said source regions being positioned parallel, adjacent to, and separated from one side of said gate stripe, all of said plurality of source regions being commonly fed; a drain region, said drain region being parallel, adjacent to, and separated from said gate, said source and drain regions lying on opposite sides of said gate; said plurality of source regions being fed by respective source feeds, all of said source feeds being connected together in common; a gate pad, said gate pad being connected to said gate stripe and being positioned within the area defined by said plurality of source feeds adjacent to one side of said gate stripe; a ground contact; and an air bridge connecting said gate pad over at least one of said source feeds to said ground contact.
Claim 12
Dependent Claim
172 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one-half microns and a greater dimension which is more than 100 microns; a plurality of drain regions, said drain regions being positioned parallel, adjacent to, and separated from one side of said gate stripe, all of said plurality of drain region being commonly fed; a source region, said source region being parallel, adjacent to, and separated from said gate, said drain and source regions lying on opposite sides of said gate; said plurality of drain regions being fed by respective drain feeds, all of said drain feeds being connected together in common; a gate pad, said gate pad being connected to said gate stripe and being positioned within the area defined by said plurality of drain feeds adjacent to one side of said gate stripe; a ground contact; and an air bridge connecting said gate pad over at least one of said drain feeds to said ground contact.
Claim 13
Dependent Claim
172 words
A monolithic common-gate active device, comprising: a gate, said gate comprising a stripe of metal having a lesser dimension of less than one and one-half microns and a greater dimension which is more than 100 microns; a plurality of drain regions, said drain regions being positioned parallel, adjacent to, and separated from one side of said gate stripe, all of said plurality of drain region being commonly fed; a source region, said source region being parallel, adjacent to, and separated from said gate, said drain and source regions lying on opposite sides of said gate; said plurality of drain regions being fed by respective drain feeds, all of said drain feeds being connected together in common; a gate pad, said gate pad being connected to said gate stripe and being positioned within the area defined by said plurality of drain feeds adjacent to one side of said gate stripe; a ground contact; and an air bridge connecting said gate pad over at least one of said drain feeds to said ground contact.
Claim 14
Dependent Claim
28 words
The device of claim 8, further comprising additional contacts to said gate near the ends of said gate, said additional contacts also being connected to said ground contact.
Claim 15
Dependent Claim
28 words
The device of claim 9, further comprising additional contacts to said gate near the ends of said gate, said additional contacts also being connected to said ground contact.
Claim 16
Dependent Claim
30 words
The device of claim 8, wherein said drain is connected by multiple separate leads to a drain feed, said multiple separate leads being spaced along the length of said drain.
Claim 17
Dependent Claim
30 words
The device of claim 9, wherein said source is connected by multiple separate leads to a source feed, said multiple separate leads being spaced along the length of said source.
Claim 18
Dependent Claim
16 words
The device of claim 8 or claim 9, wherein said gate lies on a semiconducting substrate.
Claim 19
Dependent Claim
12 words
The device of claim 14, wherein said semiconducting substrate is gallium arsenide.
References Cited (Backward Citations)
US4380022A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-21 | 1989-04-22 | 1989-10-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-21 | 1993-04-22 | 1993-10-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-21 | 1997-04-22 | 1997-10-22 | $7700.00 | Window Closed / Lapsed |