Incorporation of group V elements in GaxIn1-xAsyP1-y grown by gas source molecular beam epitaxy

A simple growth model has been successfully developed for the determination of the As to P incorporation ratio, i.e., mole fraction y, in growing GaxIn1-xAsyP1-y quaternary alloys by gas source molecular beam epitaxy. The model covers the whole composition range with only two fitting parameters, k(In) and k(Ga), whose physical meanings are the product of As to P desorption time constant ratio and incorporation rate constant ratio for InAsyB1-y and GaAsyP1-y, respectively. The best fitting values of k(In) and k(Ga), from out experimental results are 28 and 3, respectively, at a growth temperature of 480 degrees C. The temperature dependency of the parameters were also studied. The activation energies of k(In) and k(Ga) are +30 and -330 meV, respectively. The significant differences between the parameters may be due to the different bond energies of binary alloys.