Semiconductor device manufacturing: process – Forming bipolar transistor by formation or alteration of... – Forming base region of specified dopant concentration profile
Reexamination Certificate
2005-11-22
2005-11-22
Thomas, Tom (Department: 2815)
Semiconductor device manufacturing: process
Forming bipolar transistor by formation or alteration of...
Forming base region of specified dopant concentration profile
C438S349000, C257S565000, C257S592000
Reexamination Certificate
active
06967144
ABSTRACT:
A bipolar transistor structure includes a collector region having a first conductivity type formed in a semiconductor substrate. A base region is formed over the collector region; the base region includes a highly doped lower layer having a second conductivity type opposite the first conductivity type formed on the collector region and a relatively low doped (or undoped) upper layer formed on the highly doped lower layer. An emitter region having the first conductivity type is formed on the upper layer of the base region.
REFERENCES:
patent: 4086610 (1978-04-01), Clark et al.
patent: 5016075 (1991-05-01), Minato
patent: 5041892 (1991-08-01), Yano et al.
patent: 5250448 (1993-10-01), Hamasaki et al.
patent: 5315151 (1994-05-01), Hsieh et al.
patent: 5340753 (1994-08-01), Bassous et al.
patent: 5404028 (1995-04-01), Metzger et al.
patent: 5412228 (1995-05-01), Baliga
patent: 5440152 (1995-08-01), Yamazaki
patent: 5494836 (1996-02-01), Imai
patent: 5504018 (1996-04-01), Sato
patent: 5508553 (1996-04-01), Nakamura et al.
patent: 5668396 (1997-09-01), Sato
patent: 5698890 (1997-12-01), Sato
patent: 5789800 (1998-08-01), Kohno
patent: 5793067 (1998-08-01), Miura et al.
patent: 5930635 (1999-07-01), Bashir et al.
patent: 5981985 (1999-11-01), Yang et al.
patent: 6049098 (2000-04-01), Sato
patent: 6087683 (2000-07-01), King et al.
patent: 6337494 (2002-01-01), Ryum et al.
patent: 6346453 (2002-02-01), Kovacic et al.
patent: 2003/0001235 (2003-01-01), Hashimoto
patent: 1 139 408 (2001-10-01), None
King et al., Very Low Cost Graded SiGe Base Bipolar Transistors for a High Performance Modular BiCMOS Process, 1999, IEDM 99, pp. 565-568.
A. Schuppen et al. “Enhanced SiGe Heterojunction Bipolar Transistors with 160 GHz-fmax”, IEDM 95 743-746, 1995 IEEE.
Denny D. Tang, “A Reduced-Field Design Concept for High-Performance Bipolar Transistors”, IEEE Electron Device Letters, vol. 10, No. 2, Feb. 1989, pp 67-69.
Fenty Jesse A.
National Semiconductor Corporation
Stallman & Pollock LLP
Thomas Tom
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