Molecular‐beam epitaxial growth of CdTe(112) on Si(112) substrates

High crystalline quality epitaxial CdTe(112)B/ZnTe films were deposited by molecular‐beam epitaxy directly onto vicinal Si(112) substrates, without use of GaAs interfacial layers. The films were characterized with x‐ray diffraction, optical microscopy, and wet chemical defect etching. Single crystal, twin‐free CdTe(112)B films exhibit structural quality exceeding that previously reported for CdTe(112)B heteroepitaxy on GaAs/Si(112) or GaAs(112)B substrates. X‐ray rocking curve full width at half‐maximum of 72 arcsec for CdTe(224) reflection and near‐surface etch pit densities (EPD) of 2×106 cm−2 have been observed for 8‐μm‐thick CdTe films. EPD depth profiles indicate that the threading dislocation density decreases with increasing II–VI epilayer thickness up to approximately 5 μm thickness and saturates at 2×106 cm−2 for thickness exceeding 5 μm. The CdTe epilayer orientation was observed to tilt 2° away from the Si(112) substrate orientation toward the [001] direction.