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We report a 0.7×8 μm2 InAlAs-InGaAs-InP double heterojunction bipolar transistor, fabricated in a molecular-beam epitaxy (MBE) regrown-emitter technology, exhibiting 160 GHz fT and 140 GHz fmax. These initial results are the first known RF results for a nonselective regrown-emitter heterojunction bipolar transistor, and the fastest ever reported using a regrown base-emitter heterojunction. The maximum current density is J/sub E/=8×105 A/cm2 and the collector breakdown voltage V/sub CEO/ is 6 V for a 1500-/spl Aring/ collector. In this technology, the dimension of base-emitter junction has been scaled to an area as low as 0.3×4 μm2 while a larger-area extrinsic emitter maintains lower emitter access resistance. Furthermore, the application of a refractory metal (Ti-W) base contact beneath the extrinsic emitter regrowth achieves a fully self-aligned device topology.