| 摘要 |
<p>A Double Heterojunction Bipolar Transistor (DHBT) is disclosed employing a collector (5) of InP, an emitter of InP or other material such as InA1As, and a base (1) of either a selected InxGa1-xAsySb1-y compound, which preferably is lattice-matched to InP or may be somewhat compressively strained thereto, or of a superlattice which mimics the selected InGaAsSbcompound. When an emitter having a conduction band non-aligned with that of the base is used, such as InA1As, the base-emitter junction is preferably graded using either continuous or stepped changes in bulk material, or using a chirped superlattice. Doping of the junction may include one or more delta doping layer to improve the shift of conduction band discontinuities provided by a grading layer, or to permit a wider depletion region.</p> |
