SnS Thin Films Research Articles

Characterization of Nanocrystalline SnS Thin Film Fabricated used PLD Method for Photodetection Applications

Pulsed laser deposition was used to create tin sulfide (SnS) nanoparticles with a Nd:YAG laser (700 mJ) with laser pulses of (200, 250, 300, and 350 pulses). Nanoparticles were created and investigated using XRD, AFM, and UV-Vis spectroscopy to understand their optical, topographical, and electrical properties. After that, a SnS photodetector was built for the first time, and its performance, photoresponse, and sensitivity were evaluated. The development of monocrystalline SnS films was confirmed by X-ray diffraction (XRD) examination. Clear crystallization with increased crystalline size and the optimum orientation was observed in the sample synthesized SnS thin film treated with 300 pulses. The crystallite size increased from 44 at 200 to 77 nm for 350 pulses. These films were characterized by better surface morphology with (111) preferred crystals. In addition, atomic force microscopy (AFM) studies showed that the average diameter of generated SnS nanoparticles rose from (39.4 nm to 64.7) nm when the laser pulses increased in pulsed laser deposition. Transmission measurements were used to determine the films' absorption coefficient energy gap (Eg), and they showed that the optical transition was direct and that the transmittance value dropped with increasing laser pulses. Band gap energy is reduced from 2.139 to 1.773 eV. Moreover, Hall Effect measurements on all samples demonstrate that all thin films were n-type, with charge carrier concentration increasing with increased pulses and carrier mobility decreasing with increased pulses. The photodetectors ' photosensitivity was evaluated in the dark after depositing Al contacts on SnS thin films through a metal mask. The Pulses of enhancement cause a red shift in the values of particular detectivity and quantum efficiency. The highest responsivity was obtained at 350 pulses, 6.72×10−1 AW−1. The high (QE) of 150% at 200 p and detectivity of 2.9×1011 cm, Hz1/2.W-1 at 300p.

Chemical bath deposition-based synthesis of tin sulfide on silicon substrate and its application as a photodetector

Tin sulfide (SnS) is an attractive compound semiconductor for photovoltaic and sensing applications because of its abundance and non-toxicity. In the present work, the synthesis of SnS thin films on silicon substrates by chemical bath deposition (CBD) technique has been demonstrated. Tin chloride (SnCl2.2H2O) and thiourea were used as the tin and sulfur sources to deposit the SnS films with triethanolamine (TEA) as the complexing agent and sodium hydroxide (NaOH) as alkaline bath. To understand the growth mechanism, a time interrupted growth series was adopted at a temperature of 90 °C for different time durations i.e., 60 min, 120 min, and 180 min. A photosensor was fabricated using the SnS/Si heterojunction and its performance was investigated through electrical (current-voltage) and optical (photo-response) measurements. The I–V characteristics of the developed photodetector were recorded under dark and different light intensities. The device exhibited significant response to light even without a bias voltage.

Tuning of electronic properties of co-evaporated Ag:SnS thin films for heterojunction devices

Tuning of electronic properties of co-evaporated Ag:SnS thin films for heterojunction devices

The impact of silver incorporation on the structural, morphological, and optical properties of spray-pyrolyzed cubic SnS thin films

Cubic/π-SnS phase has a strong optical absorption onset and larger dielectric constant, which is favorable for solar energy conversion. Hence, these cubic SnS phase films are gaining intense interest in the research community. However, the physical properties and thus its practical application heavily depends on the synthesis condition. We present here the effects of incorporation of silver (Ag) on the physical characteristics of cubic-SnS thin films synthesized by spray pyrolysis. Ag was incorporated at different atomic concentrations of 5, 10, 15, and 20% on cubic SnS thin films. A variety of methods were used to characterize and analyze Ag-incorporated thin films. Structural and vibrational properties were analyzed using x-ray diffraction (XRD) and Raman Spectroscopy, which shows that 5 at% Ag incorporated cubic-SnS have most desirable properties. However, on higher incorporation of Ag, the deterioration of cubic SnS and formation of secondary phases (SnS2 and Sn2S3) is evident. The existence of Sn, S, and Ag ions in the necessary oxidation state has been confirmed by XPS analysis. A direct bandgap was observed in the region of 1.79 and 1.59 eV for the SnS and Ag: SnS thin films, respectively with the aid of Ultraviolet-Visible Spectroscopy (UV–vis Spectroscopy). The Photoluminescence Spectroscopy (PL) showed the near-band edge emission peak for all the samples. The needle shape morphology was observed in Scanning Electron Microscopy (SEM) images and roughness variation is estimated using optical profilometer.

Effect of molar concentration on SnS thin films using chemical spray pyrolysis technique

Effect of molar concentration on SnS thin films using chemical spray pyrolysis technique

The effect investigates of temperature on the optical and electrical properties of sprayed SnS: experimental and theoretical study

In this study, Tin monosulfide SnS semiconductor absorbers was deposited by chemical spray pyrolysis route on the glass substrate. We examined the impact of substrate temperature on the structural, morphological, linear optical and electrical characteristics of SnS absorber at many substrate temperatures such as 50 °C, 375 °C and 400 °C. The SnS films have been analysed by diverse techniques like X-ray diffraction, Raman spectroscopy, Scanning electron microscopy and UV-Vis spectrophotometer. The X-ray diffraction (XRD) spectra revealed that the SnS crystallize in the orthorhombic crystal system with the apparition of the preferential crystallographic direction oriented along (111) planes. The SEM micrographs indicate a great uniformity and granular morphological surface of SnS films. Linear optical constants such as energy gap (Eg), coefficient of extinction (k), index of refraction (n), optical conductivity (σopt), as well as the electrical properties confirm the suitable application of SnS thin films as absorber layer in the optoelectronic device applications. Additionally, we have applied the density functional theory DFT and GGA generalized gradient approximation to study the electronic characteristics; as a result of the electronic band structure the SnS absorber has a suitable energy gap.

Controlled synthesis of SnSxSe2-x thin films for solar energy water splitting

Earth-abundant and ecofriendly minerals SnSxSe2–x can be promising candidates for photoelectrochemical (PEC) cells because of their tunable band gaps and high absorption efficiency in the visible light range. In this paper, p type SnS thin films with sheet-like morphologies were successfully prepared by CBD method and then n-type SnSxSe2-x thin films were achieved by selenization annealing of SnS thin films. The physical properties and PEC performances of SnSxSe2-x thin films influenced by the annealing process were detailed studied. The photocurrent densities and stability of SnSxSe2-x films were further improved by the deposition of p-type CdS:Cu buffer layer. And the fabrication of FTO/SnSxSe2-x/CdS:Cu/TiO2/Pt photocathode improved the PEC performance further and the photocurrent as high as 10.5 mA/cm2 had been achieved. IPCE tests indicated that the FTO/SnSxSe2-x/CdS:Cu/TiO2/Pt structure achieved a power conversion efficiency of 31.3 %.

Influence Annealing Process on Structural and Optical Properties of SnS Thin Films

Thin film technology has helped offer an understanding of the crystalline structure of substances, further to the characteristics of electronic transitions and how they are used effectively in different applications. This research focused on the effect of the process of annealing on the structural and optical characteristics of tin sulfide (SnS) thin films. The technique of thermal evaporation was used to synthesize the film samples under a vacuum of about 10–7 mbar. The coated SnS thin films were annealed at 200 °C and the structural and optical characteristics parameters, such as absorbance and transmittance, as well as optical bandgap and band-tail energies in the range )300–1150( nm, were discussed. Under the influence of the annealing process, the average crystal size changed from 14 nm to 11 nm. The energy gap value increased from 1.53 eV to 1.85 eV, while Urbach energy was seen to reduce from 0.913 eV for fabricated samples to be 0.824 eV after the annealing process.

Electrochemically deposited nanostructured Cd-doped SnS thin films: Structural and optical characterizations

This paper investigates the impact of Cd-doping on the structural and optical properties of electrochemically deposited SnS thin films. The synthesized samples underwent characterization through various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman, Fourier transform infrared spectrometer (FTIR), and UV–vis spectroscopy. According to the XRD analysis, the undoped SnS material exhibited a crystallite size (D) of 20 nm. However, as the Cd-doping concentration increased, the D initially increased and then decreased. The substitutional incorporation of Cd into SnS lattice was confirmed by XRD results. The inclusion of Cd-dopant into SnS lattice was validated through EDX analysis. SEM images demonstrated that appropriate Cd-doping into the SnS lattice can enhance crystalline nucleation, growth, and morphology. The absorption spectra of Cd 2–4 samples were higher than that of Cd 1, primary due to their increased film thickness and altered morphology type. The Cd 2 and Cd 3 samples exhibited higher R % values than Cd 1, associated with their superior crystalline quality. The deposited SnS samples exhibited a very high absorption coefficient (α) ranging from 10 to 25 × 104 cm−1, making them suitable as an absorber layer. The refractive index (n) value of the Cd 2 sample at wavelengths of 400–1000 nm surpassed all other samples due to its larger crystallite size. The Eg for undoped SnS was 1.57 eV, which initially decreased to 1.30 eV and then increased to 1.81 eV after Cd-doping. The Raman analysis confirmed the successful formation of the SnS phase in all samples. Based on the obtained results, it can be concluded that the Cd-dopant improves the structural and optical characterizations of SnS thin films.

Deposition of SnS thin films on various substrates at room temperature

This study describes a modified SILAR technique for depositing Tin monosulphide (SnS) thin films on diverse substrates, such as glass, ITO coated glass, and OHP sheet, all at room temperature. This simple, less expensive, environmentally friendly, and industrially scalable method allows excellent control over the deposition rate and thickness, as well as many experimental flexibilities. The advantages of depositing films at room temperature include energy efficiency, cost-effectiveness, and suitability for heat-sensitive materials. The deposited SnS thin films underwent comprehensive analysis through XRD, FESEM, EDAX, XPS, TGA, and UV–visible spectroscopy to thoroughly understand their properties. The results showed that the films were polycrystalline, orthorhombic, single-phase, and nearly stoichiometric, with a bandgap value in the visible region. The deposition conditions were optimized to achieve high-quality thin films, and the impact of substrate variations on film characteristics was also investigated. The study showcased the simplicity of doping in the modified SILAR process. Furthermore, the study demonstrated the photocatalytic degradation effectiveness of SnS thin films against the dye Rhodamine B. Various analyses, including UV-visible spectroscopy studies, ROS scavenger tests, ROS indicator tests, and kinetic analysis, were performed. The photodegradation process was effectively described by the Langmuir-Hinshelwood (L-H) mechanism.

Effect of Cu Doping on Structural, Optical, and Electrical Properties of Sn2S3 Thin Films Prepared by Spray Pyrolysis

Effect of Cu Doping on Structural, Optical, and Electrical Properties of Sn2S3 Thin Films Prepared by Spray Pyrolysis

Performance analysis of P-SnS thin films fabricated using CBD technique for photo detector applications

In the present work, SnS thin films were prepared using the CBD technique at room temperature and varying annealing temperaturesfrom300 to 450 °C for photo detector applications. The prepared samples were characterized using different techniques for analyzing the structural, optical, morphological, and photo sensing properties of the samples. From XRD analysis, the diffraction pattern of all the prepared thin films shows the pristine SnS phase of the samples possessing an orthorhombic phase without the presence of any impurity phases. Among the fabricated thin films, the SnS thin film annealed at a temperature of 350 °C reveals the highest crystallite size. The Raman results showed the vibrational modes of SnS films and with the increase in growth temperature, the peaks are slightly shifted towards the lower wavelength region. Morphological results show that the SnS thin films exhibit a uniform morphology of 2-D petal-like morphology with different sizes. The UV-vis spectroscopic study shows the decrease in the bandgap value of the samples with the increase in annealing temperature. The photo sensing properties of the fabricated samples show the SnS sample annealed at 400 °C has a higherresponsivityvalueof6.40×10⁻²AW⁻¹,externalquantumefficiency(EQE)valueof14.9%, and the detectivity value of 6.05 × 10⁹ Jones. Finally, the transient photo response results suggest that the SnS annealed at 350 °C shows a rise and fall time of 1.5 and 2.5 s compared to the othersampleswhichwouldbebettersuitedforphotodetectorapplications. The electrical conductivity and photo-conductivity of the films increase by more than two orders with increase of film thickness from 170 nm to 915 nm. Hall Effect measurements confirm the p-type nature of the as-prepared SnS thin films.

The effect of Zn doping on the optical properties and conductivity of SnS thin film formed by chemical bath deposition

The effect of Zn doping on the optical properties and conductivity of SnS thin film formed by chemical bath deposition

High-responsivity self-powered deep-ultraviolet photodetector based on n-SnS2/p-GaN heterostructures

Deep-ultraviolet (DUV) photodetectors (PDs) have important applications in various fields, however, high manufacturing costs, complex fabrication processes, and high-power consumption limit their further development. Here, the combination of physical vapor deposition (PVD) and chemical vapor deposition (CVD) methods are used to grow in-situ vertical SnS2 (v-SnS2) thin film on a gallium nitride (GaN) substrate, thereby forming a v-SnS2/GaN p-n heterojunction (type-Ⅱ). With zero bias, the device exhibits excellent self-powered performance under 265 nm illumination. The sensor has a large responsivity of 3.525 A/W, a high specific detectivity of 1.767 × 1014 Jones, a high linear dynamic range of 97 dB, and a fast response speed (rise/decay time of 150.5/266.4 µs). This work demonstrates the great potential of SnS2/GaN heterojunction devices for deep-ultraviolet detection.

Optimization of growth of large-area SnS thin films and heterostructures for spin pumping and spin-orbit torque

Optimization of growth of large-area SnS thin films and heterostructures for spin pumping and spin-orbit torque

Broadband SnS/Te photodetector to long-wavelength infrared: breaking the spectrum limit through alloy engineering.

Materials based on group IV chalcogenides, are considered to be one of the most promising materials for high-performance, broadband photodetectors due to their wide bandgap coverage, intriguing chemical bonding and excellent physical properties. However, the reported photodetectors based on SnS are still worked at relatively narrow near-infrared band (as far as 1550 nm) hampered by the nonnegligible bandgap of 1.1-1.5 eV. Here, a novel photodetector based on Te alloyed SnS thin film was demonstrated with an ultra-broadband response up to 10.6 µm. By controlling the Te alloyed concentration in SnS increasing to 37.64%, the bandgap narrows to 0.23 eV, exhibiting a photoresponse potential at long-wavelength infrared excitation. Our results show Te-alloying can remarkably enhance the detection properties of SnS/Te photodetectors. The photoresponsivity and detectivity of 1.59 mA/W and 2.3 × 108 Jones were realized at 10.6 µm at room temperature. Moreover, the nonzero photogain was observed generated by nonlinearly increased photocurrent density, resulting in a superlinear dependency between photoresponsivity and light intensity. Our studies successfully broaden photoresponse spectrum of SnS toward the mid-infrared range for the first time. It also suggests that alloying is an effective technique for tuning the band edges of group IV chalcogenides, contributing deep implications for developing future optoelectronic applications.

Nanostructured SnS-Si hybrid photodetectors by pulsed laser processed nanocolloids

This research investigates the fabrication of SnS-Si hybrids for photodetection and photocatalysis using nanocolloids of tin sulfide (SnS), monocrystalline silicon (Sim) and polycrystalline silicon (Sip) produced by laser-assisted techniques (pulsed laser fragmentation as well as ablation in liquid). Characterization of the nanocolloids and the hybrid thin films obtained by techniques such as transmission electron microscopy (TEM), scanning electron microscopy (SEM), X-ray diffraction (XRD), X-ray photoelectron Spectroscopy (XPS), Raman spectroscopy, UV–Visible spectroscopy and photoluminescence spectroscopy (PL) are presented in this work. Post-deposition annealing improved the material properties of the hybrid films and the films exhibited optical bandgaps between 1.51 and 1.68 eV, suitable for light detection. In the case of hybrid SnS-Si films, SnS-Sim showed two orders of current higher than the SnS-Sip films. The photocurrent dynamic curves (current vs time) and current-voltage (I–V) characteristics are investigated to verify the improved device performances. The photodetector parameters such as sensitivity, responsivity, detectivity are also reported. Compared with conventional SnS thin film devices, all the films (SnS and SnS-Si hybrids) in this work responded to illumination sources of wavelengths up to 1064 nm. This is one of the initial studies on hybrid devices with Si nanoparticles for photodetector applications. All the films showed ultra-short response/recovery times in the range of 400–800 ms and their photodetector parameters were recorded. The films demonstrated good stability and cyclic photocatalytic activity to visible light.

Spray coated of newly La-doped SnS2 thin films for photocatalytic degradation application

In the present study, we present a comprehensive investigation on the synthesis and thorough characterization of La (2 and 4 at. %)-doped 2D-SnS2 thin films, which were prepared by a spray-coating method with a clear molecular ink. These thin films were specifically targeted for their potential application in photodegradation. The impact of La doping on the structural, morphological, mechanical, and electrical properties of the thin films was analyzed using a range of appropriate techniques. Additionally, the mechanical properties were assessed through Vickers micro-indentation. The results indicate that the pristine SnS2 films predominantly exhibit a preferred (101) crystal planes, while the introduction of La doping results in the appearance of a secondary Sn2S3 phase. The bandgap of the films was measured to range from 2 eV to 2.22 eV. Moreover, the thermoelectric power analysis revealed that the films exhibit n-type characteristics, and the mechanical properties showed an increase in hardness with La doping. Notably, the photocatalytic degradation rate was found to be 58.2%, 60.27%, and 62.92% for pristine SnS2, La (2 at.%)-SnS2, and La (4 at.%)-SnS2, respectively, when tested against Malachite green dyes under visible light. This enhancement in degradation efficiency can be attributed to the presence of La3+ ions, which promote electron-hole pair generation.

Annealing effect on the photocurrent response of SnS thin films prepared by the chemical spray pyrolysis method

SnS thin films were synthesized using the spray pyrolysis method and then annealed at 350, 400, and 450°C. According to the crystallographic analysis, the obtained SnS thin films crystallized in the polycrystalline orthorhombic system. The grains measured 47, 66, and 37 nm for the samples annealed at 350, 400, and 450°C, respectively. SEM and AFM images indicate that the samples’ surfaces were completely covered. Thus, the grains of SnS nanostructures have a granular-like shape and vary in size depending on the annealing temperatures. The transmittance measurement shows that annealing the sample at 400 °C extends and improves its absorption range to 600 nm. The resulting band gap energies were 1.60 eV, 1.30 eV, and 2.55 eV for annealing at 350 °C, 400 °C, and 450 °C, respectively. Hall Effect measurements reveal that annealing SnS films at 400 °C enhances their electrical properties. The values of carrier mobility, conductivity, and carrier concentration are 1.678 ×105 Cm2/Vs, 9.756 ×10-5 Ω-1 cm-1 , and 3.168 ×1010Cm-3 , respectively. Additionally, the photocurrent response validates that all samples annealed at 350, 400, and 450 °C have p-type conductivity, with values of 13, 28, and 2.5 µA/Cm2, respectively. The best conductivity, carrier mobility, and photocurrent values are obtained by annealing at 400 °C. Therefore, SnS thin films can be an interesting choice for absorber layer applications in photovoltaic systems.

Effect of substrate temperature on physical properties of Co doped SnS2 thin films deposited by ultrasonic spray pyrolysis

Ultrasonic Spray Pyrolysis (USP) was used to deposited Co doped SnS2 thin films on a glass substrate at different substrate temperatures (Ts = 350 °C, 375 °C, 400 °C, and 425 °C). DRX patterns shows that the synthesized films revealed a pure SnS2 phase with hexagonal structure. The mean crystalline grain sizes were showed an increasing– decreasing trend between 15.67 and 29.84 nm with an increment in the substrate temperature. The SEM images were significantly affected by the substrate temperature. Also, the optical band gap increases from 2.62 to 3.00 eV with the substrate temperatures increasing. Hall Effect measurements confirm the n-type conductivity of the as-deposited films. Furthermore, the films resistivity varies between 117 Ω.cm to 0.20 Ω.cm, as the substrate temperature increases from 350 to 425 °C.