Structural, optical and electrical properties of zinc oxide thin films deposited by a spray pyrolysis technique

Zinc oxide（ZnO） thin films were deposited on glass substrates by spray pyrolysis technique decomposition of zinc acetate dihydrate in an ethanol solution with 30 m L of deposition rate, the ZnO thin films were deposited at two different temperatures： 300 and 350℃. The substrates were heated using the solar cells method.The substrate was R217102 glass, whose size was 30×17.5×1 mm^3. The films exhibit a hexagonal wurtzite structure with a strong（002） preferred orientation. The higher value of crystallite size is attained for sprayed films at 350℃, which is probably due to an improvement of the crystallinity of the films at this point. The average transmittance of obtain films is about 90%–95%, as measured by a UV–vis analyzer. The band gap energy varies from 3.265 to 3.294 e V for the deposited Zn O thin film at 300 and 350℃, respectively. The electrical resistivity measured of our films are in the order 0.36 Ω·cm.

Reply to Comments on "Structural,Optical,and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique'' by K.Usharani and A.R.Balu published in Acta Metall.Sin.(Engl.Lett.) 28(1),64–71(2015)

Following are the comments for the queries raised by Prof. Pawel E. Tomaszewski on our published paper entitled ＂Structural, Optical, and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique＂ by K. Usharani and A.R. Balu published in Acta Metall. Sin.

Comments on "Structural,Optical,and Electrical Properties of Zn-Doped CdO Thin Films Fabricated by a Simplified Spray Pyrolysis Technique'' by K.Usharani and A.R.Balu Published in Acta Metall.Sin.(Engl.Lett.) 28(1),64–71(2015)

The commented paper [1] presents the results on structural, optical, and electrical properties of Zn-doped CdO thin films. Unfortunately, there are several mistakes and errors not found by any of referees. It is necessary to show these mistakes or misleading statements to avoid their use in the future papers by authors and other peoples.

Spray pyrolysis of tin selenide thin-film semiconductors:the effect of selenium concentration on the properties of the thin films

Thin films of tin selenide（Sn_xSe_y） with an atomic ratio of r =[y/x]= 0.5,1 and 1.5 were prepared on a glass substrate at T = 470℃using a spray pyrolysis technique.The initial materials for the preparation of the thin films were an alcoholic solution consisting of tin chloride（SnCl_4·5H_2O） and selenide acide（H_2SeO_3）.The prepared thin films were characterized by X-ray diffraction（XRD）,scanning electron microscopy,scanning tunneling microscopy,scanning helium ion microscopy,and UV-vis spectroscopy.The photoconductivity and thermoelectric effects of the Sn_xSe_ythin films were then studied.The Sn_xSe_y thin films had a polycrystalline structure with an almost uniform surface and cluster type growth.The increasing atomic ratio of r in the films,the optical gap,photosensitivity and Seebeck coefficient were changed from 1.6 to 1.37 eV,0.01 to 0.31 and -26.2 to—42.7 mV/K （at T = 350 K）,respectively.In addition,the XRD patterns indicated intensity peaks in r = 1 that corresponded to the increase in the SnSe and SnSe_2 phases.

Substrate temperature dependent studies on properties of chemical spray pyrolysis deposited CdS thin films for solar cell applications

Thin films of CdS have been prepared by chemical spray pyrolysis by spraying precursor solution directly onto soda lime glass（SLG） substrates. Influence of substrate temperature on structural, optical, morphological and electrical properties have been investigated by using various techniques such as low angle X-ray diffraction（XRD）, Raman spectroscopy, X-ray photoelectron spectroscopy（XPS）, field emission scanning electron microscopy（FESEM）, atomic force microscopy（AFM）, transmission electron microscopy（TEM）, UV–visible spectroscopy photoluminescence（PL） spectroscopy etc. Formation of CdS has been confirmed by low angle XRD,Raman spectroscopy and XPS analysis. XRD pattern showed that CdS films are polycrystalline, have hexagonal structure and prefer orientation of crystallites shifts from（101） to（002） with increase in substrate temperature.Raman spectroscopy revealed that exciton-phonon coupling depends on substrate temperature and hence on crystallite size. Optical band gap increased from 2.43 to 2.99 eV when substrate temperature increased from 325 to 475 ℃. Transmittance of the film also showed an increasing trend from 52% to 80% with increase in substrate temperature. Such high band gap and transmittance values of CdS films prepared at 475℃ make it a useful window material in CdS/CdTe and CdS/Cu_2S heterojunction solar cells.

Preparation of n-type semiconductor SnO_2 thin films

We studied fluorine-doped tin oxide on a glass substrate at 350℃using an ultrasonic spray technique. Tin（Ⅱ） chloride dehydrate,ammonium fluoride dehydrate,ethanol and NaOH were used as the starting material, dopant source,solvent and stabilizer,respectively.The SnO_2：F thin films were deposited at 350℃and a pending time of 60 and 90 s.The as-grown films exhibit a hexagonal wurtzite structure and have（101） orientation.The G = 31.82 nm value of the grain size is attained from SnO_2：F film grown at 90 s,and the transmittance is greater than 80%in the visible region.The optical gap energy is found to measure 4.05 eV for the film prepared at 90 s, and the increase in the electrical conductivity of the film with the temperature of the sample is up to a maximum value of 265.58（Ω·cm）^（-1）,with the maximum activation energy value of the films being found to measure 22.85 meV,indicating that the films exhibit an n-type semiconducting nature.