Process for fabricating a bipolar transistor with a self-aligned

Details Process for fabricating a bipolar transistor with a self-aligned Process for fabricating a bipolar transistor with a self-aligned

1990-02-20

1990-12-25

Chaudhuri, Olik

Fishing, trapping, and vermin destroying

437 41, 437 43, 357 33, 357 34, 148DIG11, H01L 2100, H01L 2102, H01L 21285, H01L 2972

Patent

active

049803042

ABSTRACT:
A novel fabrication method is disclosed for fabricating a bipolar transistor having a digitated emitter electrode and a contiguous polysilicon region acting as a self-aligned base contact. The process substantially reduces the parasitic capacitances as well as eliminates the need for the intrinsic base region to be exposed to multiple etching, which results in the fabrication of small and reproducible base widths.
A first polysilicon layer is deposited over the surface of a semiconductor substrate and, then, implanted with base dopants, which are driven into the surface of the active region by a furnace process for forming an intrinsic base region. Emitter dopants are next implanted into the first polysilicon layer. Subsequently, a nitride layer is deposited and the digitated emitter fingers patterned by selective etching. Link-up regions for connecting the intrinsic base region and the extrinsic base regions to be formed later is formed by implanting portions of the substrate free of the emitter fingers with base dopants. Next, oxide sidewalls are formed on the edges of the emitter fingers by depositing a conformal oxide layer and anisotropically etching the oxide layer, leaving vertical portions thereof on the edges of each emitter finger. Finally, a second polysilicon layer is deposited conformally over the entire structure and anisotropically etched back in order to form a planar, contiguous region between each finger of the digitated electrode. Implanting the entire structure with base dopants forms the extrinsic base regions outside the fingers of the digitated electrode. Heating the substrate to cause base dopants from the first polysilicon layer to diffuse into the substrate creates emitter regions under the fingers of the digitated electrode.

REFERENCES:
patent: 4319932 (1982-03-01), Jambotkar
patent: 4453306 (1984-06-01), Lynch et al.
patent: 4531282 (1985-07-01), Sakai et al.
patent: 4546536 (1985-10-01), Anantha et al.
patent: 4693782 (1987-09-01), Kikuchi et al.
patent: 4722908 (1988-02-01), Burton
patent: 4824796 (1989-04-01), Chiu et al.
Chiu, T., Nonoverlapping Super Self-Aligned Device Structure for High-Performance VLSI, IEEE Electron Device Letters, vol. 11, No. 2, Feb. 1990, pp. 85-88.
Li, G., An advanced High-Performance Trench-Isolated Self-Aligned Bipolar Technology, IEEE Trans. on Electron Devices, vol. ED-34, No. 11, Nov. 1987, pp. 2246-2253.
Chai, S., A New Self-Aligned Bipolar Transistor Using Vertical Nitride Mask, IEDM Tech. Digest., pp. 26-29, 1985.
Sakai, T., Super Self-Aligned Bipolar Technology, Symposium on VLSI Technology, Tech. Digest, pp. 16-19, 1983.
H. Nakashiba et al., "An Advanced PSA Technology for High-Speed Bipolar LSI", IEEE Transactions On Electron Devices, vol. ED-27, No. 8, Aug. 1980, pp. 1390-1394.
T. Sakai et al., "Super Self-Aligned Bipolar Technology", Symposium on VLSI Technology, Tech. Digest, pp. 16-19, 1983.
T. H. Ning et al., "Self-Aligned Bipolar Transistors for High-Performance and Low-Power-Delay VLSI", IEEE Transactions on Electron Devices, vol. ED-28, No. 9, Sep. 1981, pp. 1010-1013.
A. Cuthbertson et al., "Self-Aligned Transistors with Polysilicon Emitters for Bipolar VLSI", IEEE Transactions on Electron Devices, vol. ED-32, No. 2, Feb. 1985, pp. 242-247.
J. L. de Jong et al., "Electron Recombination at the Silicided Base Contact of an Advanced Self-Aligned Poly-Silicon Emitter", IEEE 1988 Bipolar Circuits & Technology Meeting, 1988, pp. 202-205.

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