Title :
Thermal characteristics of InGaP/GaAs HBT ballasted with extended ledge
Author :
Jeon, Sanghoon ; Park, Hyun-Min ; Hong, Songcheol
Author_Institution :
Dept. of Electr. Eng., Korea Adv. Energy Res. Inst., Taejon, South Korea
fDate :
10/1/2001 12:00:00 AM
Abstract :
A InGaP/GaAs heterojunction bipolar transistor structure is proposed in which the base epi-layer underneath the extended ledge works as a base ballast resistor. The structure eliminates the critical alignment for a passivation ledge formation as well as additional process steps for external base ballast resistors. Both ballasted and unballasted devices were fabricated and compared. A small signal equivalent circuit gives us the magnitude of the effective ballast resistance. The thermal characteristics, including gain-collapsed I-V and Vbe regression curve are shown and modeled. The temperature dependency of base sheet resistance and its influence on the device performance are also discussed
Keywords :
III-V semiconductors; equivalent circuits; gallium arsenide; gallium compounds; heterojunction bipolar transistors; indium compounds; microwave bipolar transistors; passivation; semiconductor device models; semiconductor device reliability; InGaP-GaAs; InGaP/GaAs HBT; ballasted devices; base ballast resistor; base sheet resistance; effective ballast resistance; extended ledge; gain-collapsed I-V regression curve; heterojunction bipolar transistor structure; microwave characteristics; passivation ledge formation; small signal equivalent circuit; temperature dependency; thermal characteristics; unballasted devices; Electronic ballasts; Fabrication; Gallium arsenide; Heterojunction bipolar transistors; High power amplifiers; Microwave devices; Passivation; Resistors; Temperature dependence; Thermal resistance;
Journal_Title :
Electron Devices, IEEE Transactions on
