Incorporation of Si during vapor phase epitaxy of III-V compounds: Evidence of an enthalpy-entropy compensation effect

The incorporation of dopants in III-V compound semiconductor epilayers during chemical vapor deposition involves complex homogeneous and surface reaction kinetics and is expected to be an activated process. In particular, silicon is an element of choice for n-type doping of various III-V compound epilayers for which there is a wealth of data involving different growth and doping precursors. Kinetic arguments such as the role of multi-excitation entropy or quasi-equilibration at the growth interface during incorporation predict an enthalpy-entropy compensation effect (EECE), which is observed from compiled data for more than 14 orders of magnitude of the prefactor describing the activated incorporation rate. For this particular observation of the EECE, an explanation involving data pre-selection imposed by restrictive growth conditions may also be invoked.