THE REACTIVITY OF DIMETHYLCADMIUM ON GAAS(100) AND CDTE(100)

The reactivity of dimethylcadmium (DMCd) on GaAs(100) and CdTe(100) wa s investigated by temperature programmed desorption. DMCd decomposed o n GaAs(100) yielding methyl groups that reacted with Ga atoms to form adsorbed alkylgallium complexes. These complexes desorbed in the tempe rature range 200-550 K. DMCd, on the other hand, desorbed molecularly from CdTe(100) at similar to 280K, which indicates that DMCd adsorbed reversibly on CdTe(100). Based on these results, we propose that durin g the growth of CdTe films by organometallic vapor-phase epitaxy DMCd adsorbs reversibly instead of the irreversible adsorption usually assu med in previously proposed mechanisms.