SELECTIVE ORGANOMETALLIC VAPOR-PHASE EPITAXY OF GA AND IN COMPOUNDS - A COMPARISON OF TMIN AND TEGA VERSUS TMIN AND TMGA

The present experiments show that using TEGa as the Ga source in selective OMVPE leads to a higher growth rate enhancement of GaAs and GaP than using TMGa. The combination of TEGa with TMIn (+AsH3 or PH3) yields a lower In enrichment of selectively grown GaInAs and GaInP than TMIn + TMGa. These results agree with our previous hypothesis that the differences in growth rate enhancements observed in selective OMVPE can be related to the differences in the extents of decomposition of the source species above the mask, since the decomposition temperature of TEGa is much lower than that of TMGa. We also explain why, although the decomposition temperatures of TEGa and TMIn are similar, there is still a discrepancy in the growth rate enhancements of the Ga and of the In binaries selectively grown using these source reagents.