13 June 1997 RF sputtering deposition of CdTe on GaAs substrate
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Proceedings Volume 3179, Solid State Crystals in Optoelectronics and Semiconductor Technology; (1997) https://doi.org/10.1117/12.276217
Event: XII Conference on Solid State Crystals: Materials Science and Applications, 1996, Zakopane, Poland
The fabrication of HgCdTe IR detectors demands high-quality CdTe or CdZnTe substrates. Bulk CdTe tends to twin, therefore large single crystals are generally not available. This problem could be circumvented by growing CdTe epilayers on an alternative large area substrate. Several studies have been made on the growth of CdTe on different substrates such as InSb, GaAs, Si and sapphire by MOCVD and MBE techniques. We report the initial results for the growth of CdTe buffer films on GaAs (100) substrates by sputter epitaxy. This crystal was chosen as the substrate material because of its transparency to IR radiation and availability as large area wafers with high structural perfection. Epitaxial films of CdTe were deposited in a sputtering system with a base pressure of 2 X 10-4 Pa. The GaAs substrate was degreased, etched in standard solution, and mounted immediately on a cooper substrate holder in the system. The substrates were ion etched in the sputtering system to remove surface oxide. The CdTe films were deposited in a wide substrate temperature range from 50 to 450 degrees C. Film thickness ranged from 0.1 to 5 micrometers , and deposition rates from 1 to 5 micrometers /h. The orientations and crystalline quality epitaxial films were characterized by x-ray diffraction. The surface morphology and the cross section of the gown CdTe layers were investigated by Nomarski interference contrast microscope. The optical and the electrical properties of the epitaxial films were investigated too. Structural characterization reveals that crystalline quality is a function of temperature of substrates. The single-crystals films grown at 300 degrees C on GaAs showed a best surface morphology.
© (1997) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Krzysztof Adamiec, Krzysztof Adamiec, Jaroslaw Rutkowski, Jaroslaw Rutkowski, S. Bednarek, S. Bednarek, E. Michalski, E. Michalski, } "RF sputtering deposition of CdTe on GaAs substrate", Proc. SPIE 3179, Solid State Crystals in Optoelectronics and Semiconductor Technology, (13 June 1997); doi: 10.1117/12.276217; https://doi.org/10.1117/12.276217

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