Fabrication and Characterization of CZTS Thin Films Prepared by the Sulfurization of RF-Sputtered Stacked Metal Precursors

In this work, Cu₂ZnSnS₄ (CZTS) thin films were prepared by the sulfurization of metal precursors deposited sequentially via radio frequency magnetron sputtering on Mo-coated soda-lime glass. The stack order of the precursors was Mo/Zn/Sn/Cu. Sputtered precursors were annealed in sulfur atmosphere with nine different conditions to study the impact of sulfurization time and substrate temperature on the structural, morphological, and optical properties of the final CZTS films. X-ray fluorescence was used to determine the elemental composition ratio of the metal precursors. Final CZTS films were characterized by x-ray diffraction (XRD), scanning electron microscopy (SEM), and energy-dispersive spectroscopy (EDS). XRD and EDS were combined to investigate the films’ structure and to identify the presence of secondary phases. XRD analysis indicated an improvement in film crystallinity with an increase of the substrate temperature and annealing times. Also indicated was the minimization and/or elimination of secondary phases when the films experienced longer annealing time. EDS revealed slight Sn loss in films sulfurized at 550°C; however, an increase of the sulfurization temperature to 600°C did not confirm these results. SEM study showed that films treated with higher temperatures exhibited dense morphology, indicating the completion of the sulfurization process. The estimated absorption coefficient was on the order of 10⁴ cm^?1 for all CZTS films, and the values obtained for the optical bandgap energy of the films were between 1.33 eV and 1.52 eV.     

Development of 3.7 % Efficient Cu2ZnSnSe4 Solar Cells by Selenizing Cu-Zn-Sn Films Deposited by DC Sputtering on TiN-Protected Mo/Glass Substrates

Cu₂ZnSnSe₄ (CZTSe) films for solar cell devices were fabricated by sputtering of a Cu-Zn-Sn target followed by post-selenization at 500–600 °C for 1 h in the presence of single or double compensation discs to supply Se vapor. The optimized selenization conditions avoided the Se deficiency and enhanced the grain growth of CZTSe films. The 600 °C-selenized CZTSe films adjacent with double discs obtained the large grains of 2–5 μm and had a [Cu]/([Zn]+[Sn]) ratio of 0.94 and a [Zn]/[Sn] ratio of 1.34. In order to fabricate the device on Mo-coated glass substrates, a TiN reaction barrier layer was coated before the Cu-Zn-Sn sputtering coating. The TiN-CZTSe device had 3.7 % efficiency (η), as compared to 0.58 % for the TiN-free one. The efficient device had the CZTSe layer with hole concentration (n _p) of 3.4 × 10¹⁷ cm^?3, Hall mobility (μ) of 54 cm² V^?1 s^?1, and electrical conductivity (σ) of 2.9 Ω^?1 cm^?1.     

Enhanced Thermoelectric Properties of Antimony Telluride Thin Films with Preferred Orientation Prepared by Sputtering a Fan-Shaped Binary Composite Target

p-Type antimony telluride (Sb₂Te₃) thermoelectric thin films were deposited on BK7 glass substrates by ion beam sputter deposition using a fan-shaped binary composite target. The deposition temperature was varied from 100°C to 300°C in increments of 50°C. The influence of the deposition temperature on the microstructure, surface morphology, and thermoelectric properties of the thin films was systematically investigated. x-Ray diffraction results show that various alloy composition phases of the Sb₂Te₃ materials are grown when the deposition temperature is lower than 200°C. Preferred c-axis orientation of the Sb₂Te₃ thin film became obvious when the deposition temperature was above 200°C, and thin film with single-phase Sb₂Te₃ was obtained when the deposition temperature was 250°C. Scanning electron microscopy reveals that the average grain size of the films increases with increasing deposition temperature and that the thin film deposited at 250°C shows rhombohedral shape corresponding to the original Sb₂Te₃ structure. The room-temperature Seebeck coefficient and electrical conductivity range from 101 μV K^?1 to 161 μV K^?1 and 0.81 × 10³ S cm^?1 to 3.91 × 10³ S cm^?1, respectively, as the deposition temperature is increased from 100°C to 300°C. An optimal power factor of 6.12 × 10^?3 W m^?1 K^?2 is obtained for deposition temperature of 250°C. The thermoelectric properties of Sb₂Te₃ thin films have been found to be strongly enhanced when prepared using the fan-shaped binary composite target method with an appropriate substrate temperature.     

Effects of Growth Temperature and Annealing on Properties of Zn3Sn2O7 Thin Films and Application in TFTs

The effects of growth temperature and annealing on the physical properties of Zn₃Sn₂O₇ thin films were investigated in this work. The Zn₃Sn₂O₇ thin films were deposited on glass substrates by radio frequency (rf) magnetron sputtering. It is found that the films are amorphous regardless of the growth temperature. The film grown at room temperature shows the highest mobility of 8.1 cm² V^?1 s^?1 and the lowest carrier concentration of 2.0 × 10¹⁵ cm^?3. The highest carrier concentration of 1.6 × 10¹⁹ cm^?3 is obtained at the growth temperature of 250°C. Annealing treatment of the Zn₃Sn₂O₇ thin films resulted in increases of carrier concentration and mobility. The average transmittance of the as-deposited and annealed films reaches 80%. By using a Zn₃Sn₂O₇ thin film as the channel and a Ta₂O₅ thin film as the insulating layer, we fabricated transparent Zn₃Sn₂O₇ thin-film transistors with field-effect mobility of 21.2 cm² V^?1 s^?1, on/off current ratio of 10⁵, threshold voltage of 0.8 V, and subthreshold swing of 0.8 V/decade.     

Fabrication of a Flexible Bismuth Telluride Power Generation Module Using Microporous Polyimide Films as Substrates

In this study, we investigated the effect of the structure of microporous p-type (Bi_0.4Te₃Sb_1.6) and n-type (Bi_2.0Te_2.7Se_0.3) BiTe-based thin films on their thermoelectric performance. High-aspect-ratio porous thin films with pore depth greater than 1 μm and pore diameter ranging from 300 nm to 500 nm were prepared by oxygen plasma etching of polyimide (PI) layers capped with a heat-resistant block copolymer, which acted as the template. The cross-plane thermal conductivities of the porous p- and n-type thin films were 0.4 W m^?1 K^?1 and 0.42 W m^?1 K^?1, respectively, and the dimensionless figures of merit, ZT, of the p- and n-type BiTe films were estimated as 1.0 and 1.0, respectively, at room temperature. A prototype thermoelectric module consisting of 20 pairs of p- and n-type strips over an area of 3 cm × 5 cm was fabricated on the porous PI substrate. This module produced an output power of 0.1 mW and an output voltage of 0.6 V for a temperature difference of 130°C. The output power of the submicrostructured module was 1.5 times greater than that of a module based on smooth BiTe-based thin films. Thus, the thermoelectric performance of the thin films was improved owing to their submicroscale structure.     

Thermoelectric Properties of Polycrystalline SrZn2Sb2 Prepared by Spark Plasma Sintering

Compact polycrystalline samples of SrZn₂Sb₂ [space group $ P\overline{3} m1 $ , a = 4.503(1) Å, c = 7.721(1) Å] were prepared by spark plasma sintering. Thermoelectric performance, Hall effect, and magnetic properties were investigated in the temperature range from 2 K to 650 K. The thermoelectric figure of merit ZT was found to increase with temperature up to ZT = 0.15 at 650 K. At this temperature the material showed a high Seebeck coefficient of +230 μV K^?1, low thermal conductivity of 1.3 W m^?1 K^?1, but rather low electrical conductivity of 54 S cm^?1, together with a complex temperature behavior. SrZn₂Sb₂ is a diamagnetic p-type conductor with a carrier concentration of 5 × 10¹⁸ cm^?3 at 300 K. The electronic structure was calculated within the density-functional theory (DFT), revealing a low density of states (DOS) of 0.43 states eV^?1 cell^?1 at the Fermi level.     

DLTS Analysis and Interface Engineering of Solution Route Fabricated Zirconia Based MIS Devices Using Plasma Treatment

In this work, we have fabricated low-temperature sol–gel spin-coated and oxygen (O₂) plasma treated ZrO₂ thin film-based metal–insulator–semiconductor devices. To understand the impact of plasma treatment on the Si/ZrO₂ interface, deep level transient spectroscopy measurements were performed. It is reported that the interface state density (D _it) comes down to 7.1 × 10¹⁰ eV^?1 cm^?2 from 4 × 10¹¹ eV^?1 cm^?2, after plasma treatment. The reduction in D _it is around five times and can be attributed to the passivation of oxygen vacancies near the Si/ZrO₂ interface, as they try to relocate near the interface. The energy level position (E _T) of interfacial traps is estimated to be 0.36 eV below the conduction band edge. The untreated ZrO₂ film displayed poor leakage behavior due to the presence of several traps within the film and at the interface; O₂ plasma treated films show improved leakage current density as they have been reduced from 5.4 × 10^?8 A/cm² to 1.98 × 10^?9 A/cm² for gate injection mode and 6.4 × 10^?8 A/cm² to 6.3 × 10^?10 A/cm² for substrate injection mode at 1 V. Hence, we suggest that plasma treatment might be useful in future device fabrication technology.     

Generation of High-Power Sub-THz Waves in Magnetized Turbulent Electron Beam Plasmas

Sub-THz radiation can be generated by conversion of plasma waves into electromagnetic (EM) radiation in a plasma with strong Langmuir (LT) turbulence produced via a two-stream instability of a high current relativistic electron beam (REB). Nonlinear plasmon-plasmon merging results in the generation of photons nearby the 2^nd harmonic of the plasma frequency 2ω _p (“2ω _p -process”). For plasma densities of 10¹⁴???10¹⁵?cm^?3, these frequencies are in the range of sub-THz waves at 370–570 GHz. The specific power density of sub-THz-wave emission from plasmas in the multi-mirror magnetic trap GOL-3 (at BINP) during injection of a 10-μs-REB with a current density of about 1 kA/cm² at plasma densities n _e ?≈?5?10¹⁴?cm^?3, electron temperatures T _e ?≈?1.5 keV and magnetic induction B?≈?4 T was measured to be approx. 1 kW/cm³ in the frequency band around 300 GHz. In the case of a weakly relativistic 100-μs-electron beam (90 keV) with 250 A/cm² the corresponding results are 700 W/cm³ around 90 GHz with an efficiency of 1–2 % at n _e ?≈?3?10¹³?cm^?3 (total power?≈?30 kW). Theoretical investigations show that at a density of n _e ?≈?3?10¹⁵?cm^?3 and a turbulence level of 5 % the generated sub-THz power can reach?≈?1 MW/cm³.     

Thermoelectric Properties of Al-Doped ZnO Thin Films

We have prepared 2 % Al-doped ZnO (AZO) thin films on SrTiO₃ substrates by a pulsed laser deposition technique at various deposition temperatures (T _dep = 300–600 °C). The thermoelectric properties of AZO thin films were studied in a low temperature range (300–600 K). Thin film deposited at 300 °C is fully c-axis-oriented and presents electrical conductivity 310 S/cm with Seebeck coefficient ?65 μV/K and power factor 0.13 × 10^?3 Wm^?1 K^?2 at 300 K. The performance of thin films increases with temperature. For instance, the power factor is enhanced up to 0.55 × 10^?3 Wm^?1 K^?2 at 600 K, surpassing the best AZO film previously reported in the literature.     

Sol–Gel Grown SnO<Subscript>2</Subscript> Nanoparticles: Evaluation of Structure,Morphology, and Raman Spectra

Tin oxide (SnO₂) nanoparticles (TONPs) were prepared using sol–gel method under different growth conditions. The influence of calcination temperature (450°C and 600°C) and molecular weight of polyethylene glycol (PEG 300 and PEG 4000) on the nanocrystallinity, surface morphology, and Raman spectra of as-prepared TONPs were evaluated. Variation of calcination temperature and dopant (sulfosuccinic acid, SA) was found to affect considerably the structure, surface morphology, and Raman activities of the TONPs. The size of TONPs estimated using Scherrer equation was discerned to be in the range of 15–32 nm. The observed intensity enhancement in the Raman vibrational modes at lower calcination temperature was attributed to the enlargement of TONPs size. The absorption of molecules at the TONPs surface led to a quenching in the A ₂ g and Eu Raman peaks. Raman peaks centered around 673 cm^?1, 799 cm^?1, 640 cm^?1 , and 432 cm^?1 corresponding to A1g, B2g, A1g, and Eg modes, respectively have manifested highest peaks intensity. Furthermore, the enhancement of the Eg mode due to the addition of SA dopant was ascribed to the Jahn–Teller distortion mechanism.     

Effects of Rapid Thermal Annealing on Electrical Transport in Heavily Doped ZnO Thin Films Deposited at Different Substrate Temperatures

In this work, heavily doped ZnO thin films with carrier concentrations of 1.7 × 10²⁰–1.1 × 10²¹ cm^?3 were prepared on glass substrates using direct current magnetron sputtering combined with rapid thermal annealing (RTA). The effects of RTA on the electrical transport properties of the thin films were investigated. Results showed that the resistivities of the thin films deposited at low temperatures were markedly improved due to the increased mobilities and/or carrier concentrations. Temperature-dependent Hall measurements and theoretical calculations suggested that the influence of grain boundary scattering was negligible for all the samples and the mobility was mainly determined by ionized impurity scattering. The influence of crystallographic defects on the mobility could be effectively reduced via RTA when the carrier concentration was above 4.0 × 10²⁰ cm^?3, resulting in a mobility and resistivity close to the ionized impurity scattering theoretical estimation. The highest mobility of 46 cm² V^?1 s^?1 at the resistivity of 2.8 × 10^?4 Ω cm and the lowest resistivity of 2.6 × 10^?4 Ω cm were achieved for the RTA-treated 1 wt.% Al-doped ZnO and 5 wt.% Ga-doped ZnO thin films, respectively.     

Properties of ZnO Thin Films Codoped with Lithium and Phosphorus

The properties of ZnO thin films codoped with lithium and phosphorus have been characterized. The films were deposited from high-purity ZnO and Li₃PO₄ solid targets onto c-plane sapphire substrates by radiofrequency (RF) magnetron sputtering. A substrate temperature of 900°C was determined as optimum for depositing undoped ZnO films with background electron concentration of 9.9 × 10¹⁵ cm^?3 as the buffer layer on the sapphire substrate. Postdeposition annealing was carried out using rapid thermal processing in O₂ at temperatures ranging from 500°C to 1000°C for 3 min. Analyses performed using low-temperature photoluminescence spectroscopy measurements revealed luminescence peaks at 3.356 eV, 3.307 eV, 3.248 eV, and 3.203 eV at 12 K for the codoped samples. X-ray diffraction 2θ-scans showed a single peak at about 34.4° with full-width at half-maximum of about 0.09°. Hall-effect measurements revealed initial p-type conductivities, but these were unstable and toggled between p-type and n-type over time with Hall concentrations that varied between 2.05 × 10¹³ cm^?3 and 2.89 × 10¹⁵ cm^?3. The fluctuation in the carrier type could be due to lateral inhomogeneity in the hole concentration caused by stacking faults in the films. An additional cause could be the small Hall voltages in the measurements, which could be significantly impacted by even small spikes in signal noise inherent in the measurements.     

Effects of Nb Content on the Ferroelectric and Dielectric Properties of Nb/Nd-Co-doped Bi<Subscript>4</Subscript>Ti<Subscript>3</Subscript>O<Subscript>12</Subscript> Thin Films

Nd/Nb-co-substituted Bi_3.15Nd_0.85Ti_3?x Nb _x O₁₂ (BNTN _x , x = 0.01, 0.03, 0.05 and 0.07) thin films were grown on Pt/Ti/SiO₂/Si (100) substrates by chemical solution deposition. The effects of Nb content on the micro-structural, dielectric, ferroelectric, leakage current and capacitive properties of the BNTN _x thin films were investigated. A low-concentration substitution with Nb ions in BNTN _x can greatly enhance its remanent polarization (2P _r) and reduce the coercive field (2E _c) compared with those of Bi₄Ti₃O₁₂ (BIT) thin film. The highest 2P _r (71.4 μC/cm²) was observed in the BNTN_0.03 thin film when the 2E _c was 202 kV/cm. Leakage currents of all the films were on the order of 10^?6 to 10^?5 A/cm², and the BNTN_0.03 thin film has a minimum leakage current (2.1 × 10^?6 A/cm²) under the high electric field (267 kV/cm). Besides, the C–V curve of the BNTN_0.03 thin film is the most symmetrical, and the maximum tunability (21.0%) was also observed in this film. The BNTN_0.03 thin film shows the largest dielectric constant and the lowest dielectric loss and its maximum Curie temperature is 410 ± 5°C.     

Defect Characterization in Ge/(001)Si Epitaxial Films Grown by Reduced-Pressure Chemical Vapor Deposition

We studied the microstructural characteristics and electrical properties of epitaxial Ge films grown on Si(001) substrates by x-ray diffraction, atomic force microscopy, and transmission electron microscopy. The films were grown using a two-step technique by reduced-pressure chemical vapor deposition, where the first step promotes two-dimensional growth at a lower substrate temperature. We observed a decrease in defect density with increasing film thickness. Ge films with thickness of 3.5 μm exhibited threading dislocation densities of 5 × 10⁶ cm^?2, which yielded devices with dark current density of 5 mA cm^?2 (1 V reverse bias). We also noted the presence of stacking faults in the form of lines in the films and establish that this is an important defect for Ge films grown by this deposition technique.     

Ultrafine-Grain and Isotropic Cu/SAC305/Cu Solder Interconnects Fabricated by High-Intensity Ultrasound-Assisted Solidification

With the miniaturization of portable electronic devices, the size of solder joint interconnects is decreasing to micrometer levels. These joints possess only several or even one or two grains, resulting in anisotropy and failure issues. Direct ultrasound-assisted solidification of Cu/SAC305/Cu interconnects for grain refinement and fabrication of isotropic solder joints is presented herein. These joints consist of many β-Sn grains. The average cross-sectional area of the Sn-rich phase is significantly reduced by up to 99% when compared with conventional as-reflowed samples. The ultrasonic power density exhibits a threshold value for affecting the microstructures. Below 200 W cm^?2, the β-Sn grains were refined and had circular shape. The Ag₃Sn phase grew in a manner similar to branched coral to sizes reaching 30 μm, or as rods aggregated together with Cu₆Sn₅ tube fragments. Above 200 W cm^?2, the microstructures were coarsened and Ag₃Sn had plate-like shape. The thickness of Cu₆Sn₅ intermetallic layers at the Cu/solder interfaces was reduced by more than 26%. The relationships among the ultrasonic power, nucleation rate, local temperature drop, and pressure were identified. At the highest power density of 267 W cm^?2, the nucleation rate was about 4.05 × 10¹⁴ m^?3 s^?1, the local temperature drop was 248 K, and the local pressure was on the order of several GPa.     

Synthesis and Characterization of the 25Ga2S3-(75 − x) GeS2-xCsCl System for Engineering a Chemically Stable,Mid-IR Transparent Glass

25Ga₂S₃-(75 ? x)GeS₂-xCsCl (x = 5, 10, 15, 20, 25, 30, 35, 40, 45, and 50) compositions were synthesized and characterized. The glass-forming ability of each sample corresponds to the quantity of GeS₂ and CsCl present in the sample. The density of the glasses sample was determined. Raman and Infrared (IR) spectra were conducted to determine the structures of the glasses. In the Raman spectra, the dominant GeS₂ peak is assigned at ～340 cm^?1. As the CsCl content increases over 20 mol.%, the peak broadens and separates at ～40 mol.% CsCl. As the CsCl content continues to increase, the intensity of the peak at ～315 cm^?1, which is assigned to Ga₂S₃-Cl, also increases. For the IR transmittance spectra of the glasses, five representative samples, 25Ga₂S₃-(75 ? x)GeS₂-xCsCl glasses (x = 5, 15, 30, 45, and 50), were prepared. As CsCl content increases, the absorption bands at 2.8 μm (3600 cm^?1) and 6.3 μm (1600 cm^?1), which are related to H₂O, increases. The absorption band at 7.7 μm (1600 cm^?1), which is assigned to OH^? bonding, were not changed significantly with addition of CsCl. The T _g’s range from ～400°C to 260°C as the amount of CsCl increases from 5 mol.% to 50 mol.%. The index of refraction of the Ga₂S₃-GeS₂ system is ～2.4, whereas the index of refraction of CsCl is ～1.5. Therefore, by increasing the amount of CsCl in the system, the index of refraction decreases.     

Effect of Temperature Cycling on Conduction Mechanisms in CdTe Thin Films

CdTe thin films of 500 Å thickness prepared by thermal evaporation technique were analyzed for leakage current and conduction mechanisms. Metal–insulator–metal (MIM) capacitors were fabricated using these films as a dielectric. These films have many possible applications, such as passivation for infrared diodes that operate at low temperatures (80 K). Direct-current (DC) current–voltage (I–V) and capacitance–voltage (C–V) measurements were performed on these films. Furthermore, the films were subjected to thermal cycling from 300 K to 80 K and back to 300 K. Typical minimum leakage currents near zero bias at room temperature varied between 0.9 nA and 0.1 μA, while low-temperature leakage currents were in the range of 9.5 pA to 0.5 nA, corresponding to resistivity values on the order of 10⁸ Ω-cm and 10¹⁰ Ω-cm, respectively. Well-known conduction mechanisms from the literature were utilized for fitting of measured I–V data. Our analysis indicates that the conduction mechanism in general is Ohmic for low fields <5 × 10⁴ V cm^?1, while the conduction mechanism for fields >6 × 10⁴ V cm^?1 is modified Poole–Frenkel (MPF) and Fowler–Nordheim (FN) tunneling at room temperature. At 80 K, Schottky-type conduction dominates. A significant observation is that the film did not show any appreciable degradation in leakage current characteristics due to the thermal cycling.     

Effects of Al/Sb Double Doping on the Thermoelectric Properties of Mg2Si0.75Sn0.25

Al/Sb double-doped Mg₂Si_0.75Sn_0.25 materials were prepared by liquid–solid reaction synthesis and the hot-pressing technique. The effects of Al/Sb double doping on the thermoelectric properties were investigated at temperatures between room temperature and 900 K, and the resistivity and Hall coefficient were investigated at 80 K to 900 K. Al/Sb double-doped samples were found to be n-type semiconductors in the investigated temperature range. The absolute Seebeck coefficient (α), resistivity (ρ), and thermal conductivity (κ) for Al/Sb double-doped samples at room temperature were in the ranges of 152.5 μV K^?1 to 109.2 μV K^?1, 2.92 × 10^?5 Ω m to 1.29 × 10^?5 Ω m, and 2.50 W K^?1 m^?1 to 2.86 W K^?1 m^?1, respectively. The absolute values of α increased with increasing temperature up to a maximum, and decreased thereafter. This could be attributed to mixed carrier conduction in the intrinsic region. κ decreased linearly with increasing temperature to a minimum near the intrinsic region, then increased rapidly because of bipolar components. The highest ZT value measured was 0.94 at 850 K for Mg_1.9975Al_0.0025Si_0.75Sn_0.2425Sb_0.0075. Sb doping was effective for enhancement of ZT, because of a remarkable increase in the carrier concentration. However, Al doping was almost ineffective for enhancing ZT.     

Sb2Te3 and Bi2Te3 Thin Films Grown by Room-Temperature MBE

Sb₂Te₃ and Bi₂Te₃ thin films were grown on SiO₂ and BaF₂ substrates at room temperature using molecular beam epitaxy. Metallic layers with thicknesses of 0.2?nm were alternately deposited at room temperature, and the films were subsequently annealed at 250°C for 2?h. x-Ray diffraction and energy-filtered transmission electron microscopy (TEM) combined with high-accuracy energy-dispersive x-ray spectrometry revealed stoichiometric films, grain sizes of less than 500?nm, and a texture. High-quality in-plane thermoelectric properties were obtained for Sb₂Te₃ films at room temperature, i.e., low charge carrier density (2.6?×?10¹⁹?cm^?3), large thermopower (130???V?K^?1), large charge carrier mobility (402?cm²?V^?1?s^?1), and resulting large power factor (29???W?cm^?1?K^?2). Bi₂Te₃ films also showed low charge carrier density (2.7?×?10¹⁹?cm^?3), moderate thermopower (?153???V?K^?1), but very low charge carrier mobility (80?cm²?V^?1?s^?1), yielding low power factor (8???W?cm^?1?K^?2). The low mobilities were attributed to Bi-rich grain boundary phases identified by analytical energy-filtered TEM.     

Vibrational and morphological properties of Sn-doped CdS films deposited by ultrasonic spray pyrolysis method

Cd_1?xSn_xS films (x=0.0, 0.1 and 0.2) were prepared by the ultrasonic spray pyrolysis (USP) method on the glass substrate at 300 °C. Effect of Sn doping on the vibrational and morphological properties of CdS films has been investigated by scanning electron microscopy (SEM), atomic force microscopy (AFM), FT-IR and Raman spectroscopy. The SEM and AFM measurements showed that the surface morphology of the films was affected by the tin incorporation. The Raman (200–700 cm^?1) and FT-IR (400–4000 cm^?1) spectra of Cd_1?xSn_xS were recorded. The Raman spectrum for Cd_1?xSn_xS films is dominated by an intense band at 300 cm^?1, assigned to the first-order longitudinal optic phonon and the second-order phonon peak 599 cm^?1. The absorption peaks in the FT-IR spectra of Cd_1?xSn_xS located at 540–700 and 1004–1045 cm^?1 can be assigned to the Cd–S and C–O stretching frequencies, respectively. Raman and FT-IR spectra shows decrease in the peak intensity with increasing Sn concentration.