Vertical parasitic pnp transistor in silicon germanium hbt process and manufacturing method thereof

Abstract

The invention discloses a vertical parasitic positive-negative-positive (PNP) triode in a SiGe heterojunction bipolar transistor (HBT) process. A slot which is contacted with a base region is formed in shallow slot field oxides around the base region, and the depth of the slot is less than or equal to that of the base region; polycrystalline silicon which is doped with N-type impurities is filled in the slot and forms an external base region; the external base region and the base region are contacted on the side of the base region; and metal contact is formed on the external base region and a base is led out. The invention also discloses a manufacturing method for the vertical parasitic PNP triode in the SiGe HBT process. The vertical parasitic PNP triode can be used as an output device in a high-speed and high-gain HBT circuit, one more device choice is provided for a circuit, the device area can be effectively reduced, the parasitic effect of the device can be reduced, the collector resistance of a PNP tube is reduced and the performance of the device is improved; and in the method, extra process conditions are not needed and production cost can be reduced.

Description

technical field [0001] The invention relates to the field of semiconductor integrated circuit manufacturing, in particular to a vertical parasitic PNP triode in the silicon germanium HBT process, and also relates to a method for manufacturing the vertical parasitic PNP triode in the silicon germanium HBT process. Background technique [0002] In RF applications, higher and higher device characteristic frequencies are required. In BiCMOS process technology, NPN transistors, especially silicon germanium (SiGe) heterojunction transistors (HBT) or germanium silicon carbon heterojunction transistors (SiGeC HBT) are good choices for UHF devices. And the SiGe process is basically compatible with the silicon process, so SiGe HBT has become one of the mainstreams of UHF devices. In this context, the requirements for the output device are correspondingly increased, such as having a certain current gain coefficient and cut-off frequency of not less than 15. [0003] In the prior art,...

AI Technical Summary

Problems solved by technology

The disadvantage is that the device area is large and the connection resistance of the collector is large

Since the extraction of the collector electrode in the prior art is realized through another active region adjacent to the collector region, and the other active region and the collector region need to be isolated by STI or other field oxygen, such This greatly limits the further reduction of the device size

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