| High-speed circuits based on the InGaP/GaAs system have found major application in digital IC, and in the broadband amplifiers typically employed in the optical communication systems. Currently, two common major material systems for implementing GaAs heterojunction bipolar transistor (HBTs) are employed; InGaP/GaAs and AlGaAs/GaAs. Between the two approaches, implementation of InGaP/GaAs based HBTs is the dominant choice, due to its more suitable material properties. We propose various approaches from epitaxial layer design to substrate transferred process to improve the InGaP/GaAs HBT device performance. A novel small-signal extraction method is demonstrated for the high-speed InGaP/GaAs HBT. Hybrid model is also proposed to improve the large-signal modeling for III-V HBT.; We report a substrate transferred fabrication process of InGaP/GaAs HBTs having the potential to improve speed and power performance. Our process eliminates a GaAs substrate, and transfers the epitaxial layers onto the BCB microwave dielectric by bonding the BCB with a Si substrate. The modified ballistic collector using InGaP mass filter is designed to suppress hole injection into the collector under a high current region based on the energy balance equation coupled with lattice heat equation in the Silvaco ATLAS.; A HBT small-signal parameter extraction method based on optimization under the saturation region is proposed for describing a high-speed HBT having a thin collector region. The parameters of the large-signal models, such as VBIC, MEXTRAM, and HICUM are extracted based on their DC measurement and small-signal characteristics. Hybrid model is established to combine each of the above model's advantages in order to create an initial framework that integrates both the Si and III-V bipolar transistor models. Hybrid model is implemented using Verilog-A running in Agilent ADS. |
