Patent EP0430279A2 successfully refreshed from Google Patents.
EP0430279A2
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EP
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Si/SiGe heterojunction bipolar transistor utilizing advanced epitaxial deposition techniques and method of manufacture
Assignee: HP Inc
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Filing: 1990-11-30
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Granted: —
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Expires: 2010-11-30
Abstract
Abstract A semiconductor device and the method of manufacturing that device that is a low capacitance, high speed, heterojunction semiconductor device. Such a device includes a Si substrate with a subcollector layer on top of the substrate, and a field oxide layer with a window therethrough to define the active region of the semiconductor device over a portion of the subcollector layer with a Si collector layer on top of the subcollector layer on the substrate or in the window surrounded by the field oxide. A SiGe layer is deposited non-selectively over the field oxide layer and on the collector layer in the window defining the active region. Then a dielectric layer is deposited over the SiGe layer. Finally, there are metalized contacts extending through windows in the dielectric layer above the SiGe layer and the field oxide layer making contact with the SiGe layer through one window and the subcollector layer through another window. For a transistor of the same type, the initial steps are the same and a second Si layer is deposited non-selectively over the SiGe layer before the dielectric layer is deposited with that layer now being deposited over the second Si layer. And, finally, the transistor is completed in the same way with metalized contacts extending through windows in the dielectric layer, an emitter contact above the active region making contact with the uppermost Si layer through one window, a base contact making contact with SiGe layer above the field oxide layer through a second window, and a collector contact through the field oxide layer making contact to the subcollector layer through a third window outside of the active region.
Inventors
- 👤 Theodore I. Kamins
- 👤 Albert Wang
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-10-29 23:49
CPC Classifications
H; H10; H10D; H10D10/00; H10D10/01; H10D10/021; H10D10/80; H10D10/821; H10D10/891
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
92 words
A semiconductor device comprising; a substrate (10,100); a subcollector region (12,102) on the substrate; a collector layer (14, 112) on the subcollector region; a field oxide layer (18,106) over the subcollector region and having a window therethrough defining an active region (24,108); a silicon-germanium layer (32,114) over the field oxide layer and in contact with the collector layer in the active region; a dielectric layer (38,120) over the silicon-germanium layer; means (46,128) for establishing electrical contact with the silicon-germanium layer; and means (48, 130) for establishing electrical contact with the collector layer.
Claim 2
Dependent Claim
34 words
A device according to claim 1 wherein the substrate comprises P type silicon, the subcollector region comprises N+ type silicon, the collector layer comprises N-type silicon, and the silicon-germanium layer comprises P type material.
Claim 3
Dependent Claim
24 words
A device according to claim 1 or 2 and further comprising an emitter layer (34, 116) between the silicon-germanium layer and the dielectric layer.
Claim 4
Dependent Claim
14 words
A device according to claim 3 wherein the emitter layer comprises N type silicon.
Claim 5
Independent Claim
33 words
A device according to any of claims 1,2,3, or 4 wherein the collector layer (14) underlies the field oxide layer (18) and the silicon-germanium layer (32) extends into and partially fills the window.
Claim 6
Independent Claim
28 words
A device according to any of claims 1,2,3,4, or 5 and further comprising a polycrystalline sidewall (28) adjacent vertical portions of the field oxide layer in the window.
Claim 7
Independent Claim
23 words
A device according to any of claims 1,2,3, or 4 wherein the collector layer (112) is formed in and partially fills the window.
Claim 8
Dependent Claim
24 words
A device according to claim 7 and further comprising a nitride layer (110) between the field oxide layer (106) and the silicon-germanium layer (114).
Claim 9
Dependent Claim
25 words
A device according to claim 7 and further comprising a polycrystalline silicon layer. (310) between the field oxide layer (306) and the silicon-germanium layer (312).
Claim 10
Dependent Claim
47 words
A device according to claim 7 and further comprising: an annular polycrystalline layer (420) between the field oxide layer (406) and the silicon-germanium layer (414) adjacent the window; and oxide (412) extending laterally outward from the annular layer and limiting the lateral extend of the silicon-germanium layer.
Claim 11
Independent Claim
154 words
A method of fabricating a semiconductor device, the method comprising: (a) providing a substrate structure having an upper surface comprising a field oxide layer (18, 106) with a window therethrough, the window defining an active region (24, 108), a collector layer (14, 112) accessible through the window, a subcollector layer (12,102) beneath the collector layer, and a substrate (10,100) beneath the subcollector layer; (b) non-selectively depositing a silicon-germanium layer (32,114) over the field oxide layer and that portion of the collector layer which is accessible through the window; (c) depositing a dielectric layer (38, 120) over the silicon-germanium layer; (d) opening a first contact window through the dielectric layer to the silicon-germanium layer; (e) forming an electrical contact (46,128) with the silicon-germanium layer through the first contact window; (f) opening a second contact window through the dielectric layer to the collector layer; and (g) forming an electrical contact (48, 130) with the collector layer.
Claim 12
Dependent Claim
56 words
A method according to claim 11 wherein step (a) comprises: (a1) creating the subcollector layer on the substrate; (a2) depositing the collector layer on the subcollector layer; (a3) growing the field oxide layer on the collector layer; and (a4) opening the window through the field oxide layer and thereby exposing a portion of the collector layer.
Claim 13
Dependent Claim
67 words
A method according to claim 12 wherein step (a4) comprises: depositing a polycrystalline silicon layer over the field oxide layer; growing a silicon dioxide layer over the polycrystalline layer, opening the window through the field oxide, the polycrystalline, and the silicon dioxide layers; and forming sidewalls in the window by depositing a second polycrystalline layer on exposed sides of the three layers through which the window extends.
Claim 14
Dependent Claim
63 words
A method according to claim 11 wherein step (a) comprises: (a1) creating the subcollector layer on the substrate: (a2) growing the field oxide layer over the subcollector layer. (a3) opening the window through the field oxide layer and thereby exposing a portion of the subcollector layer; and (a4) depositing the collector layer over the exposed portion of the subcollector layer in the window.
Claim 15
Dependent Claim
44 words
A method according to claim 14 and further comprising, between steps (a) and (b), the step of forming a nitride layer (110) over the field oxide layer (106) such that the nitride layer lies between the field oxide layer and the silicon-germanium layer (114).
Claim 16
Dependent Claim
45 words
A method according to claim 14 and further comprising, between steps (a) and (b), the step of forming a polycrystalline silicon layer (310) over the field oxide layer (306) such that the polycrystalline layer lies between the field oxide layer and the silicon-germanium layer (312).
Claim 17
Dependent Claim
85 words
A method according to claim 14 wherein step (b)comprises: forming an annular polycrystalline layer (420) over the field oxide layer (406) adjacent the window; forming an oxide layer (412) that extends laterally outward from the annular polycrystalline layer; and non-selectively depositing a silicon-germanium layer (414) over the annular polycrystalline layer and that portion of the collector layer which is accessible through the window, and limiting the lateral extent of the silicon-germanium layer such that the silicon germanium layer does not overlie the oxide layer (412).
Claim 18
Independent Claim
39 words
A method according to any of claims 11 through 17 wherein the substrate comprises P type silicon, the subcollector layer comprises N+ type silicon, the collector layer comprises N- type silicon, and the silicon-germanium layer comprises P type material.
Claim 19
Independent Claim
31 words
A method according to any of claims 11 through 17 and further comprising, between steps (b) and (c), the step of depositing a silicon emitter layer (34,116) over the silicon-germanium layer.
Claim 20
Dependent Claim
41 words
A method according to claim 19 wherein the substrate comprises P type silicon, the subcollector layer comprises N+ type silicon the collector layer comprises N-type silicon, the silicon-germanium layer comprises P type material and the emitter layer comprises N type silicon.
References Cited (Backward Citations)
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