摘要 |
A heterojunction bipolar transistor (HBT) (10,30) includes an indium-gallium-arsenide (InGaAs), indium-phosphide (InP) or aluminum-indium-arsenide (AlInAs) collector layer (14) formed over an indium-phosphide (InP) substrate (12). A base layer (16,32) including gallium (Ga), arsenic (As) and antimony (Sb) is formed over the collector layer (14), and an AlInAs or InP emitter layer (18) is formed over the base layer (16,32). The base layer may be ternary gallium-arsenide-antimonide (GaAsSb) doped with beryllium (Be) (16), or a strained-layer-superlattice (SLS) structure (32) including alternating superlattice (32b,32a) layers of undoped gallium-arsenide (GaAs) and P-doped gallium-antimonide (GaSb). The GaSb superlattice layers (32a) are preferably doped with silicon (Si), which is much less diffusive than Be.
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