IN-SITU OPTICAL MONITORING OF THE MOVPE GROWTH OF ZNSE ON GAAS

In situ optical reflection measurement was employed to study surface p rocesses during the MOVPE growth of ZnSe films under an alternate supp ly of diethylzinc (DEZn) and dimethylselenide (DMSe) using H-2 and/or N-2 as carrier gases. We have found that the time-dependent reflection signal exhibits a unique saw-toothed pattern during the DEZn supply, which is attributed to the adsorption and structural change of the DEZ n. In contrast, the influence of DMSe on the time-dependent signal app ears to be rather marginal. A growth mechanism is proposed based on th ese experimental results, through which the important role of ambient hydrogen is discussed.