International Journal of Computer and Information Technology (IJCIT)
In this paper, the authors address a study of bipolar transistors specified for analog and analog-digital low cost circuits, working in the radiofrequency range, dedicated to popular mobiles. These devices are fully compatible with a deeply submicronic silicon CMOS technology. Advanced epitaxial growth of strained SiGe on a silicon-germanium substrate enhances the freedom for designing high speed bipolar transistors. In this process SiGe material replaces the silicon of the base of a bipolar transistor. On the theoretical point of view, numerical method for analyzing hetero-structure semiconductor devices is described.