TRANSISTORS;
BIPOLAR DEVICES;
SEMICONDUCTOR DEVICES AND MATERIALS;
D O I:
10.1049/el:19931080
中图分类号:
TM [电工技术];
TN [电子技术、通信技术];
学科分类号:
0808 ;
0809 ;
摘要:
An optimum profile for Ge ion implantation in SiGe/Si heterojunction bipolar transistors is determined by using a two-dimensional simulator code for advanced semiconductor devices. The simulation code is based on a two-dimensional drift-diffusion model for heterostructure degenerate semiconductors with nonparabolicity included in the energy band structure. The model allows accurate simulations of carrier transport in short base devices. The simulation results indicate that for high current gain the Ge profile maximum must be close to the base-collector junction, and that the unavoidable tail of the implanted germanium in the collector region does not deteriorate the gain.