Semiconductor device manufacturing: process – Forming bipolar transistor by formation or alteration of... – Self-aligned
Reexamination Certificate
2005-07-06
2008-03-11
Whitehead, Jr., Carl (Department: 2813)
Semiconductor device manufacturing: process
Forming bipolar transistor by formation or alteration of...
Self-aligned
C257S565000, C257SE21205, C257SE21507, C438S309000
Reexamination Certificate
active
07341920
ABSTRACT:
Disclosed are embodiments of a method of fabricating a bipolar transistor with a self-aligned raised extrinsic base. In the method a dielectric pad is formed on a substrate with a minimum dimension capable of being produced using current state-of-the-art lithographic patterning. An opening is aligned above the dielectric pad and etched through an isolation oxide layer to an extrinsic base layer. The opening is equal to or greater in size than the dielectric pad. Another smaller opening is etched through the extrinsic base layer to the dielectric pad. A multi-step etching process is used to selectively remove the extrinsic base layer from the surfaces of the dielectric pad and then to selectively remove the dielectric pad. An emitter is then formed in the resulting trench. The resulting transistor structure has a distance between the edge of the lower section of the emitter and the edge of the extrinsic base that is minimized, thereby, reducing resistance.
REFERENCES:
patent: 5128271 (1992-07-01), Bronner et al.
patent: 5494836 (1996-02-01), Imai
patent: 5506427 (1996-04-01), Imai
patent: 5593905 (1997-01-01), Johnson et al.
patent: 5962880 (1999-10-01), Oda et al.
patent: 6297162 (2001-10-01), Jang et al.
patent: 6346453 (2002-02-01), Kovacic et al.
patent: 2003/0096486 (2003-05-01), Chuang et al.
patent: 2004/0150004 (2004-08-01), Aoki et al.
Jagannathan, et al., :Self-aligned SiGe NPN transistors with 285GHz fmax and 207 GHzfT in a manufacturable technology, IEEE Electron Device Letters 23,258 (2002).
J.S. Rieh, et. al., “SiGe HBTs with cut-off frequency of 350 GHz”, International Electron Device Meeting Technical Digest, 771 (2002).
Gibb & Rahman, LLC
Jr. Carl Whitehead
Luke Daniel M
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