Abstract :
The temperature dependencies of current gain are investigated in both AlGaAs/GaAs and InGaP/GaAs HBTs. Various Npn HBT structures with high C-doped bases, grown by MOCVD, have been fabricated with identical processing steps. Measured results show that base bulk recombination current plays an important role in maintaining the current gain at high temperature. In addition it is shown that both space-charge and surface recombination currents are the cause of current gain reduction with temperature
Keywords :
III-V semiconductors; aluminium compounds; carbon; electron-hole recombination; gallium arsenide; gallium compounds; heavily doped semiconductors; heterojunction bipolar transistors; indium compounds; semiconductor epitaxial layers; space charge; AlGaAs-GaAs:C; InGaP-GaAs:C; MOCVD; Npn HBT structures; base bulk recombination current; current gain reduction; current gains; high C-doped base; space-charge; surface recombination currents; temperature dependence;
