InGaAs/InP double-heterojunction bipolar transistors withgraded-InGaAsP between InGaAs base and InP collector grown by metalorganic chemical vapor deposition

摘要

The fabrication of InGaAs/InP double-heterojunction bipolartransistors (D-HBTs) grown by metal organic chemical vapor deposition(MOCVD) is described. With graded-InGaAsP layers inserted between the p+ InGaAs base and n- InP collector, the currentgain of D-HBTs with graded layers was found to be about twice as largeas that of D-HBTs without graded layers, and the dependence of collectorcurrent on collector/emitter voltage was smaller than without gradedlayers. The current gain was measured up to 2300 with 25×25 μm2 emitter area at a collector current density of 1×104 A/cm2