High gain in hybrid transistors with BAlq3∕Alq3 isotype heterostructure emitter

Abstract

We report the fabrication of permeable metal-base transistors based on bis(2-methyl-8-quinolinolato-N1,O8)-(1,1’-biphenyl-4-olato) aluminum (BAlq3)/tri(8-hydroxyquinoline) aluminum (Alq3) isotype heterostructure as emitter layer. In this transistor, n-Si was used as the collector, LiF∕Al as the emitter electrode, and Au∕Al bilayer metal as the base. We show that the leakage current is greatly reduced in Al∕n-Si∕Au∕Al∕BAlq3∕Alq3∕LiF∕Al devices with respect to Al∕n-Si∕Au∕Al∕Alq3∕LiF∕Al devices due to the utilization of BAlq3∕Alq3 isotype heterostructure emitter, leading to high common-base and common-emitter current gains at low driving voltages.