Abstract
Thermodynamic calculations, or computer simulation of the equilibrium composition, offer an excellent possibility to reduce drastically the elaborate trial-and-error experimental efforts of finding the optimal preparation conditions for MOCVD processes (temperature T, pressure P, initial composition of the vapors X), to limit them only to the P-T-X field of existence of the solid to be prepared and an acceptable yield of the product. In this communication equilibrium composition was investigated for MOCVD processes of CdTe, ZnTe, HgTe and solid solutions CdxZn1-xTe and HgxCd1-xTe. A number of volatile organometallic compounds have been used as precursors for MOCVD growth. These are dimethylcadmium (CH3)2Cd, DMCd; diethylzinc (C2H5)2Zn, DEZn; diisopropylzinc [CH(CH3)2]2Zn, DiPZn; diethyltellurium (C2H5)2Te, DETe; diisopropyltellurium [CH(CH3)2]2Te, DiPTe; methylallytellurium CH3TeCH2CHCH2, MATe. A choice of the particular combination of the precursors largely depends on the desired composition of the film to be prepared, especially in cases of solid solutions CdxZn1-xTe and HgxCd1-xTe where the vapor pressure of the precursors is instrumental for the composition of the vapor in the reaction zone and, ultimately, for the composition x of the solid solution. Equilibrium composition for II-VI telluride MOCVD systems was investigated at temperatures up to 873 K in hydrogen and inert gas atmospheres at pressures up to 1 atm. P-T-X regions of existence were outlined for each of the five materials.
Original language | English |
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Pages (from-to) | 1151-1156 |
Number of pages | 6 |
Journal | Journal of Crystal Growth |
Volume | 198-199 |
Issue number | pt 2 |
DOIs | |
State | Published - Mar 1999 |
Event | Proceedings of the 1998 10th International Conference on Vapor Growth and Epitaxy and Specialist Workshops on Crystal Growth, ICVGE-10 - Jerusalem, Isr Duration: 26 Jul 1998 → 31 Jul 1998 |