RESEARCH ACTIVITIES

My research activities focus mainly on compound semiconductor devices, physics and circuit applications. Especially this includes heterojunction bandgap engineering devices like HBTs, HEMTs, and MESFETs. Recently, Bio-chip using MEMS technology is one of my major research projects.

• Develop High-speed Devices and Circuits for 60 GHz applications
• Novel Collector-up HBT Design and Fabrication
  
• Develop GaN HBT and Its Related Process Issues
  
• Development of InP HBT Based RF Devices and Modules for 30/60 GHz Wireless Communication and Optoelectronic Integrated Circuits
  
• SiGe optoelectronics integrated circuits
  
• Switching Power Amplifier Design for High Efficiency Consideration
  
• Power Transistor Layout Consideration for Power Handeling and Cost
  
• Linearity Improvement in HBTs from Epitaxial Design.
  
• Development of InGaAsN Based HBT for Low Power Wireless and Optical Communication
• Epitaxial and layout Design of GaAs and InP Based HBTs for Ultra High Speed (fT > 120 GHz) Application.
• High Speed High Breakdown AlGaAs/GaAs (GaInP/GaAs) DHBTs with novel collector design.
• Ion Implant Isolation Technology for GaN related material.
• Development of HBT Based RF Devices and Modules for C-band Wireless Communication
• Development of GaInP/GaAs DHBTs to Power Amplifiers for Wireless Communication at Low Single Supply Voltage
• Investigate Microwave Models for pads on Si
• Model the Falloff of ft and current gainwith increasing current in SiGe HBTs
• Thin base study on AlGaAs/GaAs HBTs
• Pseudomorphic AlInP/InP Heterojunction Bipolar Transistors
• Pseudomorphic GaInP/InP MESFETs
• Selective Regrowth by CBE for HBT Applications
• High fmax Collector-up HBT's by Regrown Extrinsic Base
• AlP Barriers for GaAs FET Applications
• GaInP/GaAs/GaInP DHBTs for Power Amplifier Applications
• Current Behavior of DHBT with Thick and Low Doping Collector