The metalorganic vapour phase epitaxy of ZnTe on single crystal (100)ZnTe:P wafers is reported. The technological steps to prepare a substrate surface suitable for the high quality homoepitaxy of ZnTe are identified and optimised in terms of structural and morphological properties of overgrown epilayers. Removal of ~7 μm of material from the ZnTe:P wafers by chemical etching in 1% Br₂-methanol solution proved necessary to achieve a sufficiently smooth and homogeneous surface; in-situ H₂ heat treatment of the wafers at 350°C immediately before growth ensures optimal desorption of residual oxides, allowing epilayer crystalline quality comparable to the substrate. However, the structure of epilayers degrades for growth temperatures (TG) above 350°C due to the occurrence of stacking faults (SFs) within ~200-300 nm from the epilayer-substrate interface. Accordingly, the epilayer band-edge luminescence vanishes below 350 nm, indicating a worsening of the material radiative efficiency in very thin epilayers.
The epilayer surface morphology is the result of a complex interplay between SF nucleation and Te:Zn ad-atom stoichiometry during growth. Almost featureless morphologies are obtained for growth at 350°C, i.e. under nearly stoichiometric surface conditions. Pyramid-like hillocks develop instead for T_G ≥ 360°C, corresponding to Te-rich surface conditions, their density rapidly increasing up to around 9x10⁶ cm^-2 at T_G

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