Claims
- 1. A Schottky transistor structure having a substrate of semiconductor material of first conductivity type and an epitaxial of semiconductor material of second conductivity type deposited over said substrate, said Schottky transistor comprising:
- a. a bipolar transistor having:
- i. a collector region formed of said semiconductor material of second conductivity type formed in said epitaxial layer;
- ii. a base region of said semiconductor material of first conductivity type formed in said epitaxial layer;
- iii. an emitter region of said semiconductor material of second conductivity type formed in the surface of said base region; and
- iv. a buried collector layer of said semiconductor material of second conductivity type formed in said substrate and underlying said collector region and said base region; and
- b. a Schottky diode structure adjacent to said base region, said Schottky diode structure having a diode junction in electrical contact with said base region of said bipolar transistor, and a retrograde diode well underlying said diode junction, said retrograde diode well formed of said semiconductor material of second conductivity type in a charge carrier concentration greater than the charge carrier concentration of said epitaxial layer and distributed in a retrograde diffusion upward from said substrate, wherein said retrograde diode well is in electrical and physical contact with said diode junction,
- wherein a single contact layer on the surface of said base region and on the surface of said retrograde well, wherein said single contact layer forms a base contact of said base region and said diode junction of said Schottky diode.
- 2. The Schottky transistor structure as claimed in claim 1 further comprising a sub-emitter collector region underlying said emitter region and said base region, wherein said sub-emitter region is in physical contact with said base region and said buried collector layer.
- 3. The Schottky transistor structure as claimed in claim 1 wherein said semiconductor material of first conductivity type is P type and said semiconductor material of second conductivity type is N type.
- 4. The Schottky transistor structure as claimed in claim 3 wherein said N type semiconductor material of said retrograde diode well includes Phosphorus atoms.
- 5. The Schottky transistor structure as claimed in claim 4 wherein said retrograde diode well has a Phosphorus atom concentration of about 2.times.10.sup.16 atoms/cc near said diode junction and a Phosphorus atom concentration of about 1.times.10.sup.17 atoms/cc near said buried collector layer.
- 6. The Schottky transistor structure as claimed in claim 1 wherein said base contact and said diode junction are Platinum-Silicide junctions.
- 7. A Schottky transistor structure having a substrate of semiconductor material of first conductivity type and an epitaxial layer of semiconductor material of second conductivity type deposited over said substrate, said Schottky transistor comprising:
- a. a bipolar transistor having:
- i. a collector region formed of said semiconductor material of second conductivity type formed in said epitaxial layer;
- ii. a base region of semiconductor material of first conductivity type formed in said epitaxial layer;
- iii. an emitter region of said semiconductor material of second conductivity type formed in the surface of said base region;
- iv. a buried collector layer of said semiconductor material of second conductivity type formed in said substrate and underlying said collector region and said base region; and
- v. a sub-emitter collector region of said semiconductor material of said second conductivity type formed in said epitaxial layer underlying said base region and said emitter region; and
- b. a Schottky diode structure adjacent to said base region, said Schottky diode structure having a diode junction in electrical contact with said base region of said bipolar transistor, and a retrograde diode well underlying said diode junction, said retrograde diode well formed of said semiconductor material of second conductivity type in a charge carrier concentration greater than the charge carrier concentration of said epitaxial layer and distributed in a retrograde diffusion upward from said substrate, and wherein said retrograde diode well is in electrical and physical contact with said diode junction,
- wherein a single contact layer on the surface of said base region and on the surface of said retrograde well, wherein said single contact layer forms a base contact of said base region and said diode junction of said Schottky diode.
- 8. The Schottky transistor structure as claimed in claim 7 wherein said semiconductor material of first conductivity type is P type and said semiconductor material of second conductivity type is N type.
- 9. The Schottky transistor structure as claimed in claim 8 wherein said sub-emitter collector region and said retrograde diode well are formed of the same concentration of Phosphorus atoms.
CROSS-REFERENCE TO RELATED PATENT APPLICATIONS
This is a continuation of application Ser. No. 949,035, filed Sep. 22, 1992, now abandoned.
This invention is related to the U.S. patent applications of Murray Robinson, Christopher Joyce, and Timwah Luk, Ser. No. 803,214, filed Dec. 6, 1991, for Schottky Diode Structure With Localized Well, now U.S. Pat. No. 5,150,177 and Ser. No. 898,196, filed Jun. 12, 1992, for Fabrication Process For Schottky Diode With Localized Diode Well, now U.S. Pat. No. 5,268,316.
US Referenced Citations (5)
Non-Patent Literature Citations (3)
Entry |
IBM Technical Disclosure Bulletin, vol. 17, No. 6, Nov. 1974, New York pp. 1609-1610, R. W. Knepper. |
European Patent Application Publication No. 0500733A2. |
Patent Abstract of Japan, vol. 7, No. 292 (E-219)(1437), Dec. 27, 1983 and JP-A-58 166 765 Tokyo Shibaura Denki, Oct. 1, 1983. |
Continuations (1)
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Number |
Date |
Country |
Parent |
949035 |
Sep 1992 |
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