Abstract
CdTe crystals were grown by a modified Bridgman technique with the Cd pressure kept equal to the equilibrium value. 6N purity Cd and Te were used to synthesize the CdTe. Metallographic observation of the as-grown crystals showed that no inclusions were present. The deviation of composition from stoichiometry was investigated by microprobe analysis and was found to be below the limit of detection. The Cd and Te distribution obtained by microprobe scanning was homogeneous. Microscopic observation of preferentially etched crystals showed a dislocation density of 103 − 105cm−2. The structural perfection is good, as seen from X-ray diffraction Laue patterns. The lattice parameter determined by X-ray diffraction is 6.4846 Å. The resistivity is 103 − 105 Ω cm and the Hall mobility is about 90 cm2/V … s. The carrier concentration is 1012 − 1013cm−3 and the maximum infrared transmittance for a 100 μm thick crystal is 62%. The photoluminescence spectra indicate that the full width at half maximum (FWHM) of the 1.58 eV edge emission band is 11.2 meV and the homogeneity parameter σr = σ/〈I0〉 = 29%. The broadening parameter of the electroreflectance spectrum is less than 60 meV for the 3660 Å band and 20 meV for the 8220 Å band. Our CdTe crystals have been used as substrates for hot wall epitaxial growth of CdTe films and for the fabrication of temperature sensors coupling with optical fibers.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call