Spray pyrolysis deposition of Sn_xS_ythin films

Abstract

Tin sulphide (Sn,S,) thin films have been prepared on Pyrex glass substrates by the spray pyrolysis technique using tin chloride (SnCl,) and n, ndimethylthiourea (CH3NHCSNHCH3) as starting materials. The depositions were carried out in the range of substrate temperatures from 320 to 450 "C. From x-ray diffraction measurements and SEM micrographs, it is found that the values of x and y, which determine the type of deposited compound, depend on the substrate temperature. At lower substrate temperatures (320-360 "C), mixed phases such as SnpSs and y-SnzS3 are present. At intermediate substrate temperatures (370-390 "C), the SnS phase Is predominant. For substrate temperatures higher than 490 "C the deposited material is mainly Sn02. The optical reflectance and transmitfance of SnS were used in an iterative method to obtain the refractive index (n) and the extinction coefficient (k). These values of n and k were used to calculate the absorption coefficient (a) and the bandgap (&), giving the result EG = 1.27 eV. Measurements of the dark conductance (a) as a function of T were made and an activation energy of 0.54 eV was determined from the slope of a plot of In U versus 1 IT.

SnxSy compounds growth by controlled sulfurisation of SnO2

“…The authors have observed, in agreement with the reports of Lopez et al [45] and Thangaraju et al [46], that Sn-S compounds are predominant for sulfurisation temperatures superior to 300 • C. Koteeswara-Reddy et al [47] stated similarly that Sn x S y films grown at high temperatures were nearly stoichiometric in nature with an elemental Sn/S ratio of 1.03. In fact, under high temperatures, the Sn-O bonds are weakened inside the structure (Fig.…”

Electrical properties of PbxSn1‐xS thin films prepared by hot wall deposition method

“…As-deposited SnS films exhibited activation energy of 0.121 eV. The activation energy of the SnS films is attributed to shallow acceptor states due to Snvacancies [5,17]. These Sn vacancies are characteristics of IV-VI compounds that play a significant role in establishing the p-type conductivity of these compounds.…”

“…Devica et al [7] reported an activation energy of 0.26 eV for thermal evaporation SnS films, Noguchi et al [18] observed the activation energy between 0.28 eV and 0.34 eV in thermal evaporated SnS films. Lopez et al [17] reported an activation energy of 0.54 eV for sprayed SnS films. Therefore, the activation energy of the SnS films depends on the film thickness, the preparation technique and the film composition.…”

Structural, Optical, and Electro-Optical Properties of Thermally Evaporated Tin Sulphide Layers

“…Similar observations have been made in our previous work, reported elsewhere, and by other workers. [10][11][12][13][14] The behaviour is presented in Fig. 4.…”