High-Mobility Transport Layer Structures for Rhombohedral Si/Ge/SiGe Devices

Performance of solar cells and other electronic devices, such as transistors, can be improved greatly if carrier mobility is increased. Si and Ge have Type-II bandgap alignment in cubically strained and relaxed layers. Quantum well and superlattice with Si, Ge, and SiGe have been good noble structures to build high electron mobility layer and high hole mobility layers.