NEW PRECURSORS FOR WIDE-GAP-II-VI SEMICONDUCTORS

Recent advances in the growth of wide-gap II-VI semiconductors by MOVPE have been greatly facilitated by the development of new precursor materials. For instance, the use of adducts such as Me2ZnNEt3 and Me2Zn (triazine)2 has served to eliminate a formerly severe pre-reaction during the growth of ZnSe and ZnS and has allowed the growth of high-quality layers at low to moderate temperatures. The use of adducts has also been extended to the growth of cadmium-based II-VI alloys. The bis-tetrahydrothiophene adduct of Me2Cd has been used as a precursor to CdS and CdSe. However, in this case, pre-reaction with the group VI hydride is only slightly inhibited. From a consideration of possible reaction mechanisms we have developed a novel technique for the in situ control of gas-phase premature reactions.