Growth rate and critical temperatures to avoid the modulation of composition of InGaAs epitaxial layers

Ternary and quaternary semiconductor alloys are usually limited in their ba nd gap engineering by problems related to modulation of composition. In thi s contribution, we point out the importance of the growth rate in the evolu tion of a modulation profile in epitaxial films. As a consequence, a diagra m of phases for the epitaxial growth is proposed where a window of homogene ous composition is evidenced at low temperatures of growth. The model provi des a framework for the epitaxial growth where temperature and growth rate regulation permits the control of the composition modulation in heteroepita xies. (C) 1999 American Institute of Physics. [S0003-6951(99)00818-9].