Thermal stability of InGaAs/InP quantum well structures grown by gas source molecular beam epitaxy

Single InGaAs/InP quantum wells and superlattices grown by gas source molecular beam epitaxy were subjected to brief anneals at temperatures in the 600-850 °C range. The resulting increases in the well thickness and changes in composition were monitored by low-temperature photoluminescence and transmission electron microscopy. Very sharp well-barrier interfaces are found to be present even after annealing at the highest anneal temperature. These results can be modeled assuming diffusivity proportional to the square of concentration with D₀=7×10¹⁰ cm²/s and an activation energy of Q=5.8 eV.