رسوب نشانی الکتروشیمیایی کادمیوم تلوریم نانوکریستال

Synthesis and characterization of electrochemically

deposited nanocrystalline CdTe thin films

شناسایی و سنتز لایه های نازک نانوکریستال CdTe

به روش رسوب نشانی الکتروشیمیایی

ABSTRACT

Electrodeposition is emerging as a method for the synthesis of semiconductor thin films and nanostructures. In this work we prepared the nanocrystalline CdTe thin films on indium tin oxide coated glass substrate from aqueous acidic bath at the deposition temperature 50 ± 1 °C. The films were grown potentiostatically from −0.60 V to −0.82 V with respect to saturated calomel reference electrode. The structural, compositional, morphological and optical properties were investigated using X-ray diffraction (XRD), energy dispersive analysis by X-rays (EDAX), atomic force microscopy (AFM), and UV–vis spectroscopy respectively and cyclic voltammetery. The structural and optical studies revealed that films are nanocrystalline in nature and possess cubic phase, also the films are preferentially oriented along the cubic (1 1 1) plane. The effect of cadmium composition on the deposited morphology was also investigated. The size dependent blue shift in the experimentally determined absorption edge has been compared with the theoretical predictions based on the effective mass approximation and tight binding approximation. It is shown that the experimentally determined absorption edges depart from the theoretically calculated values.

 

رسوب نشانی لایه های نازک زیرکونیای پایدار شده با ایتریا

Yttria-stabilized zirconia thin films deposited by

pulsed-laser deposition and magnetron sputtering

رسوب نشانی لایه های نازک زیرکونیای پایدار شده با ایتریا،

به روش رسوب دهی لیزری پالسی  و کندوپاش ماگنترونی

ABSTRACT

Yttria-stabilized zirconia (YSZ, ZrO2:Y2O3) was deposited on (100) silicon by two physical vapor deposition techniques: pulsed laser deposition (PLD) and reactive magnetron sputtering (RMS). PLD thin films were grown on silicon substrates at 500 °C from the ablation of a 8YSZ ceramic target by a KrF excimer laser. RMS thin films were obtained by direct current magnetron sputtering of a Zr/Y metallic target in an oxygen/argon atmosphere. The deposition rate of the PLD technique using an UV excimer laser delivering pulses at a repetition rate of 40 Hz was found two orders of magnitude lower than the RMS method one. Both techniques led to the growth of crystalline films with a (111) preferential orientation. PLD films were dense and featureless whereas RMS ones exhibited well defined but compact columnar structure. Growth of a YSZ film of about 1 μm covering a rough and porous commercial anode support (NiO–YSZ cermet) was successfully carried out with both methods.