HETEROJUNCTION BIPOLAR TRANSISTOR AND ITS MANUFACTURING METHOD

摘要

PROBLEM TO BE SOLVED: To provide a high performance heterojunction bipolar transistor exhibiting excellent machinability without increasing on-resistance (Ron). SOLUTION: The heterojunction bipolar transistor has a first collector layer 3 formed between an n-type GaAs sub-collector layer 2 and a second n-type GaAs collector layer 4 having an impurity concentration lower than that of the sub-collector layer 2. The first collector layer 3 exhibits tolerance to an etching liquid employed in the etching process of the second collector layer 4 and does not impede the conductivity of electrons at a joint to the second collector layer 4. COPYRIGHT: (C)2007,JPO&INPIT