The effective distribution coefficient of phosphorus during growth of Ga1minus;xAlxAs1minus;yPyby liquidhyphen;phase epitaxy is of particular importance to the growth of heteroepitaxial structures for injection lasers and lighthyphen;emitting diodes. In these structures small additions of P (y0.02) can be used for stress compensation and for lowering of laser threshold. In this work, Auger spectroscopy was combined with ion milling for quantitative chemical analysis and depth profiling. Belowy=0.02 (withx=0.36) and cooling rate of 0.1thinsp;deg;C/min for growth,kpwas found to be 290 at a growth temperature of 790thinsp;deg;C and remained constant down to at leasty=0.002. This high value ofkpcaused depletion of P from the growth solution and gave rise to P concentration profiles in the epitaxial layer which decreased with distance away from the substrate.
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