Liquid phase epitaxial growth of lattice mismatched InSb, GaInAs and GaInAsSb on GaAs substrates using a quaternary melt

We have developed and established a unique technique for growing highly lattice mismatched ternary and quaternary compounds on binary substrates using a quaternary melt thermo-chemistry. In this technique, growth is initiated from a pseudo-quaternary melt on compatible substrates. Growth of GaInAs, InAsSb, GaInAsSb and InSb epilayers on GaAs has been achieved using In-Ga-As-Sb melts. The grown epilayers have a uniform composition and are very thick (>100μm). Between the GaAs substrate and the uniform composition epilayer, there exists a graded composition quaternary which is found to be extremely beneficial in relieving misfit. No specific efforts were made to change growth conditions (during epi-growth) to compositionally grade the buffer layers. Hence, this growth scheme is extremely simple to implement and can be used for the growth of a variety of alloy semiconductors by appropriately selecting the growth temperature and melt composition. One of the key highlights of this work is the growth of InxGa1-xAsySb1-y epilayers with cut-off wavelength of 10μm on GaAs substrates. This paper will discuss the melt thermo-chemistries and the process for this new epilayer growth method.