Title :
Current transport mechanism in GaInP/GaAs heterojunction bipolar transistors
Author :
Liu, William ; Fan, Shou-Kong ; Kim, Tae S. ; Beam, Edward A., III ; Davito, David B.
Author_Institution :
Texas Instruments Inc., Dallas, TX, USA
fDate :
8/1/1993 12:00:00 AM
Abstract :
GaInP/GaAs heterojunction bipolar transistors (HBTs) and both graded and abrupt AlGaAs/GaAs HBTs were fabricated. A total of 20 wafers were analyzed. Comparisons of the experimental results establish that the dominant carrier transport mechanism in GaInP/GaAs HBTs is the carrier diffusion through the base layer. This suggests that the conduction-band barrier across the GaInP/GaAs emitter-base junction is so small that the barrier spike does not affect the carrier transport. This result differs from other published results which, by studying device structures other than HBTs, determined the conduction band barrier to be as large as ~50% of the bandgap difference. The findings of the present investigation, however, agree well with another published work which also examined an HBT structure. The difference between these works is discussed
Keywords :
III-V semiconductors; carrier mobility; diffusion in solids; gallium arsenide; gallium compounds; heterojunction bipolar transistors; indium compounds; AlGaAs-GaAs; GaInP-GaAs; HBT structure; HBTs; bandgap difference; base layer; carrier diffusion; carrier transport mechanism; conduction-band barrier; emitter-base junction; heterojunction bipolar transistors; Current measurement; Gallium arsenide; Heterojunction bipolar transistors; Indium phosphide; Interpolation; PIN photodiodes; Photoelectricity; Photonic band gap; Thermionic emission; Uninterruptible power systems;
Journal_Title :
Electron Devices, IEEE Transactions on
