Patent US3092599A successfully refreshed from Google Patents.
← Back to Patent Explorer
US4079408A Expired / Lapsed US ⏱️ 0.0 years remaining

Semiconductor structure with annular collector/subcollector region

Assignee: International Business Machines Corp
•
Filing: 1975-12-31
•
Granted: 1978-03-14
•
Expires: 1995-12-31
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract Disclosed is a semiconductor structure with an annular collector/subcollector region. The base area with the emitter, is positioned over the collector/subcollector region only, resulting in a smaller base to collector capacitance. Packing density is improved and circuit design flexibility is provided by the ability to change the emitter size without changing the size of the overall structure.

Inventors

  • 👤 Theodore William Kwap
  • 👤 Ingrid Emese Magdo

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 07:09
CPC Classifications
H; H10; H10D; H10D84/00; H10D84/60; H10D84/611; H10D84/613; H10D84/617; H10D62/00; H10D62/10; H10D62/13; H10D62/137

Claims Analysis

Total Claims: 23
Claim 1
Independent Claim 121 words
A semiconductor structure comprising: a substrate; an annular subcollector region formed by semiconductor material doped with an impurity of a first conductivity type in said substrate; at least one base region formed by semiconductor material doped with an impurity of a second conductivity type over at least a portion of said subcollector region and defining a base-collector PN junction; at least one emitter region formed by semiconductor material doped with an impurity of said first conductivity type substantially in said at least one base region and over said subcollector region and defining a base-emitter PN junction; said annular subcollector region laterally surrounding a region having a higher resistivity than said annular subcollector region, said region of higher resistivity comprising insulating material.
Claim 2
Dependent Claim 121 words
A semiconductor structure comprising: a substrate; an annular subcollector region formed by semiconductor material doped with an impurity of a first conductivity type in said substrate; at least one base region formed by semiconductor material doped with an impurity of a second conductivity type over at least a portion of said subcollector region and defining a base-collector PN junction; at least one emitter region formed by semiconductor material doped with an impurity of said first conductivity type substantially in said at least one base region and over said subcollector region and defining a base-emitter PN junction; said annular subcollector region laterally surrounding a region having a higher resistivity than said annular subcollector region, said region of higher resistivity comprising insulating material.
Claim 3
Dependent Claim 42 words
A semiconductor structure as in claim 1 wherein said region having a higher resistivity further comprises: semiconductor material doped with an impurity of said first conductivity type and having an impurity concentration lower than the impurity concentration of said annual subcollector region.
Claim 4
Dependent Claim 34 words
A semiconductor structure as in claim 2 wherein said region of higher resistivity extends to a major surface of said substrate and is adapted for the formation of at least one Schottky barrier diode.
Claim 5
Dependent Claim 16 words
A semiconductor structure as in claim 1 wherein said insulating material comprises: an oxide of silicon.
Claim 6
Dependent Claim 39 words
A semiconductor structure as in claim 4 wherein said oxide of silicon is silicon dioxide formed by in situ conversion of portions of said semiconductor material within the area defined by the outer periphery of said annular subcollector region.
Claim 7
Dependent Claim 27 words
A semiconductor structure as in claim 1 further comprising: an isolating material laterally surrounding said entire structure thereby isolating said structure from other portions of said substrate.
Claim 8
Dependent Claim 16 words
A semiconductor structure as in claim 6 wherein said isolating material comprises an oxide of silicon.
Claim 9
Dependent Claim 48 words
A semiconductor structure as in claim 1 wherein said annular subcollector region defines a polygon, said at least one base region being formed over each section of said polygon, an emitter region being formed in each said at least one base region over each section of said polygon.
Claim 10
Dependent Claim 139 words
A multiemitter integrated semiconductor transistor structure comprising: a semiconductor substrate having first and second major surfaces; an annular subcollector region formed with the semiconductor substrate by highly doping said semiconductor substrate material with an impurity of a first conductivity type; at least one base region formed by semiconductor material doped with an impurity of a second conductivity type over at least a portion of said subcollector region and defining a base-collector P-N junction; an emitter region formed substantially in the at least one base region over at least a portion of the subcollector region by a semiconductor material doped with an impurity of said first conductivity type and defining a base-emitter P-N junction; said annular subcollector region laterally surrounding a region having a higher resistivity than said annular subcollector region; and said region of higher resistivity comprising insulating material.
Claim 11
Dependent Claim 139 words
A multiemitter integrated semiconductor transistor structure comprising: a semiconductor substrate having first and second major surfaces; an annular subcollector region formed with the semiconductor substrate by highly doping said semiconductor substrate material with an impurity of a first conductivity type; at least one base region formed by semiconductor material doped with an impurity of a second conductivity type over at least a portion of said subcollector region and defining a base-collector P-N junction; an emitter region formed substantially in the at least one base region over at least a portion of the subcollector region by a semiconductor material doped with an impurity of said first conductivity type and defining a base-emitter P-N junction; said annular subcollector region laterally surrounding a region having a higher resistivity than said annular subcollector region; and said region of higher resistivity comprising insulating material.
Claim 12
Dependent Claim 39 words
A semiconductor structure as in claim 7 wherein said oxide of silicon is silicon dioxide formed by in situ conversion of portions of said semiconductor material outside an area defined by the inner periphery of said annular subcollector region.
Claim 13
Dependent Claim 25 words
A semiconductor structure as in claim 7 wherein said isolating material comprises, at least in part, a doped isolation region under said oxide of silicon.
Claim 14
Dependent Claim 46 words
A multiemitter integrated semiconductor transistor structure as in claim 9 having an epitaxial layer over at least a portion of said substrate, said at least one base region, said base-collector P-N junction, said emitter region, and said base-emitter P-N junction being formed in said epitaxial layer.
Claim 15
Dependent Claim 44 words
A multiemitter integrated semiconductor transistor structure as in claim 9 wherein said region having a higher resistivity comprises: semiconductor material doped with an impurity of said first conductivity type and having an impurity concentration lower than the impurity concentration of said annular subcollector region.
Claim 16
Dependent Claim 37 words
A multiemitter integrated semiconductor transistor structure as in claim 13 wherein said region of higher resistivity extends to a major surface of said substrate and is adapted for the formation of at least one Schottky barrier diode.
Claim 17
Dependent Claim 19 words
A multiemitter integrated semiconductor transistor structure as in claim 9 wherein said insulating material comprises: an oxide of silicon.
Claim 18
Dependent Claim 42 words
A multiemitter integrated semiconductor transistor structure as in claim 15 wherein said oxide of silicon is silicon dioxide formed by in situ conversion of portions of said semiconductor material within an area defined by the outer periphery of said annular subcollector region.
Claim 19
Dependent Claim 30 words
A multiemitter integrated semiconductor transistor structure as in claim 9 further comprising: an isolating material laterally surrounding said entire structure thereby isolating said structure from other portions of said substrate.
Claim 20
Dependent Claim 19 words
A multiemitter integrated semiconductor transistor structure as in claim 17 wherein said isolating material comprises, an oxide of silicon.
Claim 21
Dependent Claim 41 words
A multiemitter integrated semiconductor transistor structure as in claim 18 wherein said oxide of silicon is silicon dioxide formed by in situ conversion of portions of said semiconductor material outside an area defined by the inner periphery of said subcollector region.
Claim 22
Dependent Claim 28 words
A multiemitter integrated semiconductor transistor structure as in claim 18 wherein said isolating material comprises, at least in part, a doped isolation region under said oxide of silicon.
Claim 23
Dependent Claim 50 words
A multiemitter integrated semiconductor transistor structure as in claim 9 wherein said annular subcollector region defines a polygon, said at least one base region formed over each section of said polygon, an emitter region being formed in each said at least one base region over each section of said polygon.

References Cited (Backward Citations)

US3229119A Cited
US3482111A Cited
US3510736A Cited
US3909837A Cited
US3622842A Cited
US3648125A Cited
US3774088A Cited
US3916431A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1981-03-13 1981-09-12 1982-03-14 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1985-03-13 1985-09-12 1986-03-14 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1989-03-13 1989-09-12 1990-03-14 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag