| 摘要 |
A heterostructure bipolar transistor (HBT) and related methods are disclosed. In one embodiment, the HBT includes a substrate; a polysilicon emitter atop the substrate; a collector in the substrate; at least one isolation region adjacent to the collector; an intrinsic base including monocrystalline silicon germanium extending over each isolation region; and a monocrystalline extrinsic base. One method includes replacing isolation region formation with formation of porous implanted silicon, which is later converted to a dielectric. As a result, a monocrystalline silicon germanium profile base layer may be formed with extended lateral dimensions over the isolation region(s).
|
