Interface roughness in short-period InGaAs∕InP superlattices

Electron mobility was studied in lattice-matched short-period InGaAs∕InP superlattices as a function of the width of the wells. The decreasing mobility with decreasing well width was shown to occur due to the interface roughness. The roughnesses of InGaAs∕InP and GaAs∕AlGaAs interfaces were compared. Much smoother InGaAs∕InP interfaces resulted in higher electron mobility limited by interface roughness.