Investigation of Upper and Lower Limits of Carrier Concentration for Two-Dimensional Electron Gas in Strained Silicon

Both the simulation and experimental results confirm that there exist upper and lower limits of carrier concentration in the quantum well. The small difference between the upper and lower limits explains the narrow distribution of 2DEG density from all published experimental observations in strained Si. We report the lowest as-grown carrier density to date in Si/SiGe heterostructures