EP0076105A2
Expired / Lapsed
EP
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Method of producing a bipolar transistor
Assignee: Fujitsu Ltd
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Filing: 1982-09-23
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Granted: —
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Expires: 2002-09-23
Abstract
Abstract A method of producing a bipolar transistor comprises the steps of forming a base region (41), forming a high-melting-point metal layer (42) of a base electrode on the base region (41), forming a first insulating layer (43) on the metal layer (42), and selectively etching the first insulating layer (43) and the metal layer (42) to form an opening (45). A second insulating layer (46) is formed on the sides of the first insulating layer (43) and the metal layer (42) within the opening (45), the second insulating layer (46) defining an emitter-providing region. impurities are introduced into the base region (41) by using the second insulating layer (43) as a mask to form an emitter region (49). An emitter electrode (51) and the base electrode (42) are arranged in a like multilayer structure.
Inventors
- 👤 Hiroshi Goto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 18:44
CPC Classifications
H; H10; H10D; H10D48/00; H10D48/30; H10D48/32; H10D48/34; H10D48/345; H10D64/00; H10D64/01; H10D64/011; H10D64/0111; H10D64/20; H10D64/27; H10D64/281; H10P; H10P76/00; H10P76/40; Y; Y10; Y10S; Y10S148/00; Y10S148/01; Y10S148/04
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
81 words
A bipolar transistor, comprising a base region, an emitter region, and a base electrode, characterised in that the base electrode (42) is made of a high-melting-point metal and is placed on a portion of the base region (41); an insulating layer (43,46) is formed on at least the sides of the base electrode and defines an emitter-providing region; and the emitter region (49) is formed by introducing impurities into the base region (41) by using the insulating layer as a mask.
Claim 2
Dependent Claim
81 words
A bipolar transistor, comprising a base region, an emitter region, and a base electrode, characterised in that the base electrode (42) is made of a high-melting-point metal and is placed on a portion of the base region (41); an insulating layer (43,46) is formed on at least the sides of the base electrode and defines an emitter-providing region; and the emitter region (49) is formed by introducing impurities into the base region (41) by using the insulating layer as a mask.
Claim 3
Dependent Claim
59 words
A bipolar transistor according to Claim 1, characterised in that the insulating layer comprises a first insulating layer (43) placed on the upper surface of the base electrode (42) and a second insulating layer (46) placed on the sides of the first insulating layer (43) and the base electrode (42) and on a portion of the base region (41).
Claim 4
Dependent Claim
24 words
A bipolar transistor according to Claim 1 or Claim 2, characterised in that the insulating layer comprises phosphosilicate glass, silicon nitride, or aluminium oxide.
Claim 5
Dependent Claim
20 words
A bipolar transistor according to any preceding claim, characterised in that the high-melting-point metal (42) is gold, molybdenum, or tungsten.
Claim 6
Dependent Claim
37 words
A bipolar transistor according to Claim 4, characterised in thai the base electrode (42) comprises a gold layer and a thin alloy layer which is formed under the gold layer and is made of titanium-platinum or titanium-palladium.
Claim 7
Independent Claim
125 words
A method of producing a bipolar transistor having a base region, an emitter region, and a base electrode, characterised by the steps of depositing a high-melting-point metal on the base region (41) to form the base electrode (42); forming a first insulating layer (43) on the base electrode (42;; selectively etching the first insulating layer (43) and the base electrode (42) to form an opening (45) in which a portion of the base regiol. (41) is exposed; forming a second insulating layer (46) on the sides of the base electrode (42) and the first insulating layer (43) within the opening (45); and introducing impurities into the base region (41) by using the second insulating layer (43) as a mask to form an emitter region (49).
Claim 8
Independent Claim
125 words
A method of producing a bipolar transistor having a base region, an emitter region, and a base electrode, characterised by the steps of depositing a high-melting-point metal on the base region (41) to form the base electrode (42); forming a first insulating layer (43) on the base electrode (42;; selectively etching the first insulating layer (43) and the base electrode (42) to form an opening (45) in which a portion of the base regiol. (41) is exposed; forming a second insulating layer (46) on the sides of the base electrode (42) and the first insulating layer (43) within the opening (45); and introducing impurities into the base region (41) by using the second insulating layer (43) as a mask to form an emitter region (49).
Claim 9
Dependent Claim
87 words
A method according to Claim 6, characterised in that the step of forming the second insulating layer (46) comprises the steps of forming a third insulating layer including the second insulating layer and having a greater thickness than the total thickness of the first insulating layer (43) and the base electrode (42) on the first insulating layer (43) and on the exposed portion of the base region (41), and anisotropically etching the third insulating layer so as to leave the second insulating layer lying on said sides.
Claim 10
Dependent Claim
21 words
S. A method according to Claim 8, characterised in that the anisotropical etching is reactive sputter etching or reactive ion-beam etching.
References Cited (Backward Citations)
No citation records indexed.
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