A method and structure of enhancing the current gain of bipolar junction transistors.

摘要

Prodn. of a bipolar junction transistor (BJT) comprises: (a) forming a patterned SiO2 layer (60) superjacent a semiconductor substrate (10) with a base, an emitter and a collector to enable a carrier current to conduct between the base and emitter, the patterned SiO2 layer (60) exposing an interface (16) on the substrate (10) at the emitter; (b) forming a first polysilicon layer (70) superjacent the patterned SiO2 layer (60) and the interface (16); (c) implanting the first polysilicon layer (60) with O2; and (d) heating the substrate (10) such that the interface (16) is obstructed by a SiO2 formation to block a portion of the carrier current from passing through the interface. Also claimed is a method of fabricating a BJT with doped conductivity, or to increase current gain.