MBE-based materials growth for high f/sub T/ SiGe HBT

In this paper, the technology of MBE-based materials growth for high cutoff frequency (f/sub T/) SiGe HBTs was described. To grow a high-performance SiGe/Si hetero-junction multiple-structure, technologies such as the doping of secondary implantation (DSI), low-temperature doping, and antimony (Sb) surface pre-deposition, have been presented in the course of molecular beam epitaxy (MBE). The cutoff frequency of a mesa SiGe HBT, which was developed by using a SiGe/Si hetero-junction multi-structure, reached 105 GHz. In addition, key technologies such as the wafer surface pre-treatment before epitaxial growth, the temperature control of SiGe layer growth, etc., were introduced in detail.