رسوب دهی لیزر پالسی لایه های نازک CdTe و اثر دمای زیرلایه

CdTe thin films grown by pulsed laser deposition

using powder as target: Effect of substrate temperature

لایه های نازک CdTe رشد کرده به روش رسوب دهی لیزر پالسی و با استفاده از

پودر به عنوان ماده هدف : اثر دمای زیرلایه

ABSTRACT

CdTe thin films were deposited by pulsed laser deposition on Corning glass slides using CdTe powder as target. Films were grown at substrate temperatures ranging from room temperature (~25 °C) to 300 °C. The structural, compositional and optical properties were analyzed as a function of substrate temperature. X-ray diffraction shows that CdTe films grown at room temperature have hexagonal phase, while for higher temperatures the films have cubic phase. Raman and EDS indicate that films grew with Te excess, which suggests that CdTe films have p-type conductivity.

 

شناسایی و سنتز نانوکریستال های CdTe شفاف فوتولومینسنت

Synthesis and characterization of

brightly photoluminescent CdTe nanocrystals

شناسایی و سنتز نانوکریستال های CdTe شفاف فوتولومینسنت

ABSTRACT

A new synthesis procedure for the preparation of spherical shaped CdTe nanocrystals (NCs) is presented, exhibiting bright luminescence with exceptionally high quantum efficiency (up to 85%). The growth of these NCs occurs in a non-coordinating solvent, octadecene, with the addition of oleic acid/tri-octylphosphine stabilizers, CdO as a precursor for the Cd monomers and additional Cd metal particles as a supplementary Cd reservoir source. The dependence of the crystalline quality and the optical properties of the CdTe NCs, on the initial Cd:Te precursors’ molar ratio, and the reaction duration were investigated. It was demonstrated that the NCs’ properties improved significantly as the initial Cd:Te molar ratios are increased. The obtained NCs’ properties were correlated with measurements of the Cd0 concentration in Cd metal particles, CdTe NCs and in Cd monomer solutions.