Wider latitude for sophisticated devices by incorporating carbon into crystalline Si or SiGe
Research on highly supersaturated, carbon-containing alloys on silicon substrates started only a few years ago. Meanwhile, knowledge has been accumulated on growth, strain manipulation, thermal stability, carbon effects on band structure and charge carrier transport. We review basic mechanical and electrical material properties of Si1?yCy and Si1?x?yGexCy layers grown pseudomorphically on Si(001). Adding carbon alleviates some of the constraints for strained Si1?xGex, and opens new possibilities for device application of heteroepitaxial Si-based systems. The incorporation of carbon is beneficial for: (i) improving SiGe layer properties; (ii) creating layers with new properties; and (iii) controlling dopant diffusion in microelectronic devices. A large variety of applications in microelectronic devices appears likely. The first device application ready for production is the npnSiGe:C heterojunction bipolar transistor (HBT) with excellent static and high frequency performance.
heterojunction bipolar transistor group iv alloys silicongermanium carbon incorporation