Patent ID: 6043519
Filing Date: 2000-03-28
Classification: H01L

Abstract:
A Junction High Electron Mobility Transistor-Heterojunction Bipolar Transistor (JHEMT-HBT) monolithic microwave integrated circuit (MMIC), comprising:a substrate;an emitter-channel layer over said substrate;an implant through said emitter-channel layer that defines and isolates coplanar HBT emitter region and JHEMT channel;coplanar emitter contact and source and drain contacts, said emitter contact interfused into said emitter region and said source and drain contacts interfused into said channel;a composite modulation layer configured and positioned to form a heterojunction with said emitter-channel layer and to supply high mobility free electrons to said channel;a base-gate layer positioned above said emitter-channel layer, said base-gate layer patterned to form coplanar HBT base mesa and JHEMT gate pedestal that are respectively arranged over said emitter region and said channel;coplanar base and gate contacts on a first portion of said base mesa and on said gate pedestal, respectively;an HBT collector pedestal on a second portion of said base mesa; anda collector contact on said collector pedestal,said HBT emitter region, base mesa and collector pedestal forming a collector up vertical HBT and said JHEMT channel and gate pedestal forming a horizontal JHEMT.