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2D tin chalcogenides are promising materials for thin-film solar cells due to their excellent characteristics. SnS1−xSex alloy films have garnered attention from researchers over the last few decades due to their tunable physical features. Here, we report the successful preparation of SnS1−xSex powder using a temperature-assisted mechanochemical process and their subsequent deposition on glass substrates via thermal evaporation. X-ray diffraction (XRD) and Raman spectroscopy were used to extensively analyse SnS1−xSex thin films, elucidating their structural characteristics. The presence of a ternary alloy has been verified by both energy dispersive X-ray spectroscopy (EDAX) and X-ray photoelectron spectroscopy (XPS). The absorption spectrum shows that TSSe thin films have great potential for absorbing a wide range of visible light. Hall measurement revealed that n-type TSSe thin films have shown great promise with the highest hall mobility of up to 16.7 cm2 V−1 s−1. Our study demonstrates that TSSe has excellent potential as a 2D material for cutting-edge photovoltaic applications. [ABSTRACT FROM AUTHOR]

Multiferroic materials capable of robust magnetoelectric coupling at room temperature are currently being explored for their possible multifunctional device applications. Highly (100)-oriented Pb(Fe0.5Ta0.5)x(Zr0.53Ti0.47)1−x (PZTFTx) thin films (x = 0.2 and 0.3) with a thickness of about 300 nm were grown on La0.67Sr0.33CoO3 (LSCO)-buffered MgO 100-oriented substrates via the pulsed laser deposition method. An analysis of their X-ray diffraction patterns suggests the stabilization of the orthorhombic phase in the thin films at room temperature. Dielectric spectroscopic measurements of the metal–insulator–metal (Pt/PZTFTx/LSCO) thin-film capacitors as a function of temperature revealed a diffuse ferroelectric-to-paraelectric phase transition around Tm ~520 and 560 K for the x = 0.2 and 0.3 thin films, respectively. Well-saturated electrical hysteresis loops with large remanent (Pr) and saturation (Ps) polarizations were observed in these capacitors, which indicates the establishment of intrinsic ferroelectric ordering in the thin films at room temperature. These thin films retained ferromagnetic/ferrimagnetic ordering up to 300 K and showed saturation magnetization values of 8.3 (x = 0.2) and 6.1 (x = 0.3) emu/cm3 at room temperature. The magnetoelectric coupling constants of 2040 mV/cmOe (x = 0.2) and 850 mV/cmOe (x = 0.3), respectively, were obtained at an in-plane bias field at room temperature. The present study demonstrates that PZTFTx thin films are multiferroic at room temperature with large magnetoelectric couplings, and these materials may be suitable for use in magnetic sensors and spintronic device applications. [ABSTRACT FROM AUTHOR]

Alloy engineering are efficient methods to improve the physical properties of two‐dimensional (2D) material‐based photovoltaic application. Tin chalcogenide belonging to layered structured semiconducting family has been a significant compound due to its outstanding characteristics. Tin selenide (SnSe) is known as promising layered compound to develop 2D materials for optoelectronic devices. The current study focused onto the effect of tin sulfoselenide (SnSSe) alloy engineering on the structural, morphological, optical, and electrical characteristics. X‐ray Diffraction (XRD) confirmed that SnSSe and SnSe are exist in the orthorhombic crystal structure phase without other secondary phases, with the preferred high‐intensity peak along (111) oriented plane. Raman spectra was reported to give information about the vibrational characteristics of the compounds. The presence of Sulfur ion in SnSSe was further confirmed by Energy Dispersive X‐ray Spectroscopy (EDAX) and X‐ray Photoelectron Spectroscopy (XPS) analysis. Bandgap energy (Eg) has been analysed by Tauc's plot and the derivative of transmittance spectra. According to both sets of analyses, the bandgap of the SnSSe thin film is considerably smaller than that of the SnSe thin film. Hall measurements indicated that SnSSe exhibits the higher hole mobility. The present work's results offer useful insight into the prospective device applications of two‐dimensional alloy materials. [ABSTRACT FROM AUTHOR]

Magnetoelectric (ME) composite thin films are promising candidates for novel applications in future nanoelectronics, spintronics, memory, and other multifunctional devices as they exhibit much higher ME coupling and transition temperatures (Tc) than well-known single phase multiferroics discovered to date. Among the three types of multiferroic composite nanostructures, (2–2) layered and (1–3) vertically aligned composite nanostructures exhibit comparatively smaller ME coupling due to different shortcomings that restrict their use in many applications. Here, we study the morphological, piezoresponse force microscopic (PFM), ferroelectric, magnetic, and magnetodielectric properties of 0–3 [magnetic nanoparticles (0) homogeneously distributed in ferroelectric matrices (3)] multiferroic composite thin films. The Pb(Fe0.5Nb0.5)O3 (PFN)–Ni0.65Zn0.35Fe2O4 (NZFO) particulate composite films were synthesized by pulsed laser deposition. These particulate composite thin films are completely c-axis oriented with very low surface roughness. We observed magnetic and ferroelectric Tc above room temperature (RT) for all composite thin films. The PFN–NZFO 0–3 composites exhibit large polarization, high saturated magnetization with low coercive field, and low dielectric loss along with magnetodielectric coupling at RT. These nanocomposites might be utilized in next generation nano/microelectronics and spintronic devices. [ABSTRACT FROM AUTHOR]

Optical and structural properties of pulsed laser-deposited CdSSe thin films were grown using different temperatures on different substrates. The results of optical and structural investigation show that these films are suitable for optoelectronics applications. The energy band gap lies in the range that is suitable for the desired purpose. x-ray diffraction (XRD) analysis indicated preferential orientation in the (220) direction. The band gap energy of these films is in the range of 2.277 to 2.641 eV. [ABSTRACT FROM AUTHOR]

Vanadium sesquioxide V2O3, a transition metal oxide, is an important metal transition insulator due to its potential applications in novel electronic and memory devices. V2O3 thin films of thickness around 230 nm were grown on Si/SiO2/Ti/Pt substrates at deposition temperature of 723 K in a controlled Ar:O2 atmosphere of 35:2.5 sccm employing Direct Current (DC) magnetron sputtering. X-ray diffraction studies confirmed single phase of the material stabilized in corundum rhombohedral R 3 ¯ C phase. X-ray photoelectron spectroscopic results revealed chemical oxidation states are of V3+ and O2− and have nearly stochiometric elemental compositions in the films. Magnetization studies down to 10 K predicts a canted antiferromagnetic transition around 55 K. Out of 7 expected Raman active modes (2A1g + 5Eg), two A1g Raman active modes at 242 and 500 cm−1 were observed at ambient R 3 ¯ C phase. Temperature dependent Raman spectroscopic studies carried out from 80 to 300 K identified a monoclinic to rhombohedral phase transition at ~143 K. [ABSTRACT FROM AUTHOR]

In the present investigation, ZnO thin films were deposited on an ITO coated glass substrate using the Pulsed Laser Deposition technique at different annealing temperatures, from 150 to 300 °C. Investigation showed the post-annealing process affected the topological structure and optical properties of ZnO thin films, which were investigated by Atomic Force Microscopy (AFM), and UV–Vis spectroscopies respectively. Temperature-dependent Raman spectroscopy and X-ray Diffraction (XRD) were used to confirm the presence of ZnO material. Surface roughness was analyzed by the AFM technique which indicates that it is slightly affected by annealing temperature. Optical transmittance data showed high transmittance about ∼ 70% within the visible region. The direct energy bandgap, complex refractive index, the complex dielectric constant was calculated through transmittance and absorption data. The optical band gap was 3.143 eV, firstly dropped to 3.112 eV and then increased to 3.171 eV with increasing the annealing temperatures. The surface roughness of ZnO thin films was associated with variations in optical band gap, indicating that the post-growth annealing method has a substantial impact. [ABSTRACT FROM AUTHOR]

With the rapid development of new device miniaturization technology, there is invigorated interest in magnetic nanostructures for potential application in novel multifunctional devices. In continuation to our search for a suitable magnetic material having Curie temperature (Tc) well above room temperature for multifunctional applications, we have studied the dielectric, optical, magnetic, and resistance switching characteristics of Ni0.65Zn0.35Fe2O4 (NZFO) thin films. The observation of only (004) reflection in the X-ray diffraction patterns confirms the c-axis orientation and high quality growth of NZFO thin films. The presence of mixed valences of Fe2+/Fe3+ cations is probed by X-ray photon spectroscopy, which supports the cationic ordering-mediated large dielectric response. Our investigations reveal NZFO to be an indirect band gap material (~1.8eV) with a direct gap at ~2.55eV. These nanostructures exhibit high saturation magnetization and a low coercive field with a ferrimagnetic-paramagnetic phase transition of ~713K. Magnetic force microscopy studies revealed the stripe-like domain structure of the investigated thin films. In addition, these thin films exhibit reliable and repeatable unipolar resistive switching characteristics. The observed high dielectric permittivity with low loss tangent, large magnetization with soft magnetic behavior, striped magnetic domain structure and reliable resistance switching in NZFO thin films above room temperature suggest potential application in memory, spintronics, and multifunctional devices. [ABSTRACT FROM AUTHOR]

The evolution of device miniaturization and the potential application for next-generation nonvolatile memory devices Pb(Zr0.53Ti0.47)0.60(Fe0.5Ta0.5)0.40O3 (PZTFT) can be used as a barrier in multiferroic tunnel junctions. We report single-phase magnetoelectric multiferroic ultra-thin PZTFT at room temperature. The magnetic and ferroelectric properties have been investigated down to 7 nm thickness which are requisite properties for multiferroic tunnel barriers for multi-states memory applications. In the present study, we show that it remains a switching multiferroic at room temperature down to at least thickness d = 7 nm, which is thin enough for tunnel junctions. [ABSTRACT FROM AUTHOR]

We studied the resistive memory switching in pulsed laser deposited amorphous LaHoO3 (a-LHO) thin films for non-volatile resistive random access memory applications. Nonpolar resistive switching (RS) was achieved in Pt/a-LHO/Pt memory cells with all four possible RS modes (i.e., positive unipolar, positive bipolar, negative unipolar, and negative bipolar) having high RON/ROFF ratios (in the range of ~104-105) and non-overlapping switching voltages (set voltage, VON~±63.6-4.2V and reset voltage, VOFF~±1.3-1.6V) with a small variation of about 65-8%. Temperature dependent current-voltage (I-V) characteristics indicated the metallic conduction in low resistance states (LRS). We believe that the formation (set) and rupture (reset) of mixed conducting filaments formed out of oxygen vacancies and metallic Ho atoms could be responsible for the change in the resistance states of the memory cell. Detailed analysis of I-V characteristics further corroborated the formation of conductive nanofilaments based on metal-like (Ohmic) conduction in LRS. Simmons-Schottky emission was found to be the dominant charge transport mechanism in the high resistance state. [ABSTRACT FROM AUTHOR]

Bi5FeTi3O15 (BFTO) based Aurivillius rerroelectrlc thin films were rabrlcated on strontium ruthanate coated amorphous ffised silica substrates using pulsed laser deposition technique. Optical, rerroelectrlc, and piezoresponse properties or these thin films were investigated. The estimated refractive index (n) and extinction coefficient (k) for these films were in the range from 2.40 to 2.59 and 0.012 to 0.19, respectively. The bandgap or the BFTO thin layers was estimated to be 2.88 eV. Domain switching and hysteresis loops or BFTO films were studied utilizing piezoresponse force microscopy (PFM). The measured apparent polarization (Pr) and coercive field (Ec) for the samples were 20 µC/cm² and 250kV/cm, respectively. The amplitude and phase hysteresis curves obtained from PFM characterization reveal that these films can be switched below 5 V. These results suggest that BFTO in thin film form is a promising material for photo rerroelectrlc and optoelectronic devices applications. [ABSTRACT FROM AUTHOR]

Magnetoelectric multiferroics, because of their coupled electric and magnetic ordering in a single phase, are eminent for applications in logic and nonvolatile memory devices. Recent advances in computational modeling, synthesis, and characterization techniques are spurring significant advances in the study of these materials. During last several years, our group at University of Puerto Rico has been involved in synthesizing novel single-phase room temperature multiferroic materials that included not only solid solutions of lead zirconate titanate with lead iron tungstate, lead iron niobate, and lead iron tantalate, but also recently discovered palladium substituted room temperature multiferroics, namely PbPd0.3Ti0.7O3 and Pb(Zr0.2Ti0.8)Pd0.3O3. In this review, we have reported thin films of the above materials that were synthesized using pulsed laser deposition technique on various substrates at Speclab, University of Puerto Rico. We describe in detail thin film fabrication, structural diffraction analyses (XRD, TEM), dielectric, ferroelectric, piezo-response force microscopy, and magnetization results on recently grown Pd-substituted lead titanate and lead zirconate titanate thin films in an elaborate manner. The films were phase pure and stabilized in c-axis oriented tetragonal phase (P4mm) with surface roughness RQ of 2–4 nm. Temperature-dependent dielectric studies on metal-dielectric-metal heterostructure capacitors indicate that ferroelectric to paraelectric phase transition is above 500 K. A proof of ferroelectricity was confirmed from strong domain switching responses using piezo-response force microscopy. These films showed ferromagnetic ordering below 395 K. The origin of magnetic ordering in these materials was attributed to the existence of Pd2+ and Pd4+ mixed oxidation states of palladium dispersed in the polar matrices. We conclude with the above findings that these multiferroics may have potential applications.in nonvolatile memory and other multifunctional devices. [ABSTRACT FROM AUTHOR]

Amorphous YCrO3 (YCO) films were prepared on Pt/TiO2/SiO2/Si substrate by pulsed laser deposition in order to investigate resistive switching (RS) phenomenon. The Pt/YCO/Pt device showed stable unipolar RS with resistance ratio of ∼105 between low and high resistance states, excellent endurance and retention characteristics, as well as, non-overlapping switching voltages with narrow dispersions. Based on the x-ray photoelectron spectroscopy and temperature dependent switching characteristics, observed RS was mainly ascribed to the oxygen vacancies. Moreover, current-voltage characteristics of the device in low and high resistance states were described by Ohmic and trap controlled space-charge limited conduction mechanisms, respectively. [ABSTRACT FROM AUTHOR]

Antimony doped p-type ZnO films were grown on Al2O3 (0001) substrate by pulsed laser deposition. The structural properties of Zn1-xSbxO (3% and 5%) thin films were investigated by Raman scattering studies. The softening of local lattice due to the formation of (SbZn-2VZn) acceptor complexes was detected as the shift in E2high mode toward lower frequency side in ZnSbO thin films. Additional optical modes observed at 277, 333, 483, and 534 cm-1 are due to the breaking of translational symmetry in w-ZnO by Sb doping. The Zn-Sb related local vibrational mode was detected around 237 cm-1 in 5% Sb doped ZnO thin film. Room temperature Hall measurements exhibited low resistivity of 0.017 Ω cm, high hole concentration of 6.25×1018 cm-3, and mobility of 57.44 cm2/V s in the 5% Sb-doped ZnO thin film. [ABSTRACT FROM AUTHOR]

CuAlO2 thin films were grown on single crystalline sapphire substrates with c-axis orientation by rf sputtering method. The x-ray diffraction data indicate the formation of delafossite structure and tend to be oriented along (001). Temperature dependent Raman spectra of CuAlO2 thin films were measured from 80 to 1273 K, and we observed two optical modes at Eg (∼418 cm-1) and A1g(∼767 cm-1) showing anomalous frequency and linewidth shifts with temperature, which were interpreted as an experimental evidence of combined effect of lattice expansion and anharmonic phonon-phonon interaction in CuAlO2. At high temperature, polaronic state and change in effective mass due to lattice expansion also affect the frequency shift and the linewidth of the observed Raman modes. [ABSTRACT FROM AUTHOR]

Bismuth zinc niobate (Bi1.5Zn1.0Nb1.5O7) thin films were deposited on fused silica substrates by pulsed laser deposition. Its phase composition and microstructure were characterized by x-ray diffraction and atomic force microscopy. The as deposited films were amorphous and all of them were crystallized after a postdeposition annealing at 600 °C for 30 min in air. The crystallite size of the films was found to be varying between 31 and 60 nm with respect to the oxygen pressure in the deposition chamber. The films were found to be less oriented with the decreasing crystallite size. The films deposited under different oxygen pressures showed a microwave dielectric permittivity in between 98–124 and a loss tangent in between 0.005 and 0.007 over the X-band frequency range. From the Raman scattering data of the bulk and thin films, it was found that the Raman modes in thin films are relatively more intense and additional Raman modes were appearing in the films in the low frequency range, which reveal that the local symmetry in the films is different from that of the bulk. The variations in the microwave dielectric properties due to processing can be attributed to the change in the local symmetry of the film. [ABSTRACT FROM AUTHOR]

SrBi[SUB2]Ta[SUB2]O[SUB9] thin films on various bottom electrodes/substrates such as Pt/TiO[SUB2]/SiO[SUB2]/Si (Pt) and LaNiO[SUB3]/Pt/TiO[SUB2]SiO[SUB2]/Si (LNO) were grown using the pulsed laser deposition technique. X-ray diffraction studies revealed that as-grown (at 500°C) films were crystallized in the layered structure after annealing at 800°C. Films grown on platinized silicon exhibited maximum value of remanent polarization (2P[SUBr]˜21.5μC/cm[SUP2]) with coercive field (E[SUBc]) of˜67 kV/cm. The dielectric constant and dissipation factor also decreased with the introduction of a 50 nm conducting LaNiO3 oxide electrode at the interface of Pt and SBT thin films, which might be contributed by the high resistive oxide electrode layers. The dc leakage characteristics of the films were studied at elevated temperatures and the data were fitted with the Schottky emission model. The barrier heights of the films grown on Pt and LNO substrates were estimated to be 1.27 and 1.12 eV with optical dielectric constants of 6.3 and 17, respectively. The reduction in barrier height was attributed to the lower work function of the LNO electrode. [ABSTRACT FROM AUTHOR]

Temperature stability of voltage tunability and figure of merit (FOM) were investigated for the pulsed laser deposited Ba0.6Sr0.4TiO3(BST0.6) thin films on platinum coated silicon [Pt(111)/TiOx/SiOx/Si(100)] substrates. The structural and micro-structural properties of these films were analyzed using x-ray diffraction (XRD) and atomic force microscopy (AFM), respectively. Metal-ferroelectric-metal (MFM) mono-dielectric layer stacks were fabricated using these films and their temperature and voltage dependent dielectric properties were quantified. The temperature dependence of dielectric properties were analysed using the modified Curie-Weiss law. The films showed a good dielectric tunability of about 40% at a bias field of 125 kV/cm. The determined figure of merits are found to be highly sensitive to the temperature changes. The observed ferroelectric-like behaviour in these films above the Curie point (Tc) has been attributed to the thermal expansion mismatch and the substrate induced misfit strain with the Pt/Si substrate. [ABSTRACT FROM PUBLISHER]

We report a remarkable photovoltaic effect in pulsed laser deposited multiferroic aurivillius phase Bi5FeTi3O15 (BFTO) thin films sandwiched between ZnO:Al transparent conductive oxide top electrode and SrRuO3 bottom electrode fabricated on amorphous fused silica substrates. The structural and micro structural properties of these films were analysed by X-ray diffraction and atomic force microscopy techniques. The films were showing a photo sensitive ferroelectric behaviour with a notable apparent polarization in the range of 10-15 μC/cm². These films also exhibited a switchable photoresponse and this parameter was observed to be sensitive to polarisation field and the polarization direction. The device shows a large ON/OFF photo current ratio with an open circuit voltage of 0.14 V. The photo response at zero bias of this BFTO based heterostructures showed rapid increase to a saturation value of 6 μA at zero bias. [ABSTRACT FROM AUTHOR]

Multilevel resistive switching was observed in random access memory device using amorphous SmGdO3 (SGO) ternary oxide thin films. Non-volatile and stable 4-level resistance states with sufficient margin of resistance ratios were observed by varying compliance current which was attributed to compliance current dependent variation in size of conducting filaments. As fabricated Pt/SGO/Pt devices exhibited excellent switching parameters such as stable resistance ratios of reset (ON) to set (OFF) states, non-overlapping switching voltages, excellent data retention, and endurance. Temperature dependent variation of resistances of ON and OFF states of the device was studied to elucidate current conduction and resistive switching mechanisms. [ABSTRACT FROM AUTHOR]

PbZr0.53Ti0.47O3/CoFe2O4 multilayer nanostructures were grown on La0.5Sr0.5CoO3 coated MgO and Pt/TiO2/SiO2/Si substrates by pulsed laser deposition. Ferroelectric polarization decreased slowly in reducing the temperature from 300 to 200 K, with complete collapse of polarization at 100 K, but there was complete recovery of the polarization during heating. At the same time, the temperature dependent remanent magnetization of the multilayer nanostructures showed slow enhancement in the magnitude till 200 K with three-fold increase at 100 K compared to room temperature. Thus the enhancement in remanent magnetization and the decrease in polarization on lowering the temperature suggest that dynamic the magnetoelectric coupling existed in the multilayer systems. [ABSTRACT FROM AUTHOR]

The magnetic properties of BiFeO3(BFO) - CoFe2O4(CFO) heterostructure thin films, grown on (100), (110) and (111) SrTiO3 (STO) substrates by employing pulsed laser deposition (PLD) method, have been studied. The XRD patterns of BFO-CFO multilayer thin films compared with the pure CFO and BFO thin films grown using under identical conditions evidenced that all peaks present correspond to CFO and BFO structure in two separate phases. Micro-Raman spectra analysis also reveals the presence of BFO and CFO in two separate phases in the heterostructures thin films. The anomalous enhancement in magnetization has been observed for BFO-CFO multilayer thin films, relative to pure BFO thin films in all three different orientations. The saturation magnetization for (100), (111) and (110) oriented BFO-CFO thin films are 44, 62 and 80 emu/cc suggesting that (110) is most preferable direction to achieve the magneto electric (ME) coupling effect. [ABSTRACT FROM AUTHOR]

Development of lead-free BaTiO3/NiFe2O4/BaTiO3 (BTO/NFO/BTO) trilayer structure thin films is significant for the realization of eco-friendly and implantable microelectromechanical systems (MEMS)-based devices. In the present work, we report BTO/NFO/BTO trilayer structure as a representative ferroelectric/ferromagnetic/ferroelectric (FE/FM/FE) system deposited on Pt(111)/TiO2/SiO2/Si using Pulsed Laser Deposition (PLD) technique. We report the ferroelectric, magnetic, and ME properties of BTO/NFO/BTO trilayer nanoscale heterostructure having dimensions 140/80/140 nm, at room temperature. High room temperature dielectric constant ~2145 at 100 Hz with low dielectric loss ~0.05 at 1 MHz is observed. Further, the deposited (BTO/NFO/BTO) tri-layered thin films showed magnetoelectric, multiferroic behavior with remanent polarization of 8.63 μCcm−2 at about 0.25 MV/cm and a reasonably high saturation magnetization of ~16 emu/cm3 at ~10 kOe is witnessed at room temperature. Tri-layered films have shown interesting magnetoelectric (ME) coupling coefficient (αE) ~54.5 mV/cm Oe at room temperature. [ABSTRACT FROM AUTHOR]

Comparative studies of the microstructure, micro-Raman spectroscopy, and dielectric properties of PbSc0.50Nb0.25Ta0.25O3 (PSNT) thin films and nanoceramics were carried out over a wide range of temperature (100–520 K) and frequency (100 Hz to 1 MHz). The microstructure of PSNT films revealed an in-plane compressive strain, whereas PSNT nanoceramics showed an average grain size of 10–15 nm although these nanoordered regions are not capable of producing relaxor behavior. We have observed a shift of 65 K in the dielectric maxima temperature in PSNT films toward the lower temperature side compared with bulk, which confirms the in-plane compressive strain in the films. We have proposed a dielectric model to calculate the shift in dielectric maxima temperature. Using our experimental data of PSNT thin films, the theoretical model predicted a shift of 62 K in the dielectric maxima temperature, which matched well with our experimental observation. The modified Curie–Wiess law showed a broad relaxation (γ∼2) and a higher disorder level (δ=90 K) for PSNT thin films compared with PSNT nanoceramics having γ∼1.60 and δ=15 K. Well-behaved hysteresis loops were observed in a broad temperature range for PSNT thin films and slim hysteresis for nanoceramics, indicating a relaxor ferroelectric and diffused ferroelectric phase transition (DFPT) nature, respectively. The temperature-dependent micro-Raman spectroscopy revealed that the ferroelectric state in PSNT nanoceramics was accompanied by the appearance of a new peak as a shoulder at ∼80 cm−1 to the lowest F2g mode ∼57 cm−1. Its half-widths and intensity reduced to zero near the phase transition temperature, whereas the A1g mode showed a doublet namely at (805 and 830 cm−1) below DFPT and an intermediate singlet frequency at 820 cm−1 above DFPT. The micro-Raman spectra for the thin film matched quite well with the nanoceramics, except that the missing second F2g mode at ∼360 cm−1 was interpreted due to a shorter coherence length in the dipole arrangement in thin films. The in-plane compressive strain, dipole arrangement, and the size of the nanoordered regions vary the dielectric response of the PSNT films compared with the nanoceramics. [ABSTRACT FROM AUTHOR]

PbSc0.5Nb(1 -x)/2Tax/2O3(PSNT for x = 0.3, PST for x = 1) nanoceramics and thin films were prepared by high energy ball mill with solid state reaction technique and pulse laser deposition (PLD) respectively. A comparative study of the microstructure, dielectric properties, and polarization of PSNT and PST thin films and nano ceramics were carried out over a wide range of temperature (100 K-600 K) and frequency (100 Hz to 1 MHz). High Resolution Transmission Electron Microscopy (HRTEM) image of PSNT and PST thin films indicate the presence of small polar nano regions (PNRs) and long range ordered regions in crystal lattice plane respectively. PST nanoceramics (PST-N) showed normal ferroelectric behavior where as its thin film form (PST-F) illustrated relaxor behavior. PSNT nanoceramics (PSNT-N) and its films (PSNT-F) demonstrated weak frequency dispersion and strong frequency dispersion in dielectric spectra respectively. A shift in dielectric maximum temperature (Tm) towards lower temperature side i.e. 65 K and 85 K were observed for PSNT-F and PST-F compare to their nanoceramices indicates greater role of substrate-electrode-interface strain on dielectric properties. Well behaved hysteresis at room temperature for PSNT-F point toward strong competition between short range order and long range order. A weak slim hesteresis for PST-F were observed at room temperature suggesting the existence of polar nano regions far above dielectric maximum temperature. [ABSTRACT FROM AUTHOR]

Thin films of BaZr0.25Ti0.75O3 in which Ba2 + is partially substituted by Ca2 + are prepared by a sol-gel method. Phases and dielectric properties of the films are studied.The crystal structure of BaZr0.25Ti0.75O3 is cubic and does not change with Ca substitution upto x = 0.25 in Ba1-xCaxZr0.25Ti0.75O3. A change from a normal to relaxor behavior is observed for x = 0.20 as indicated by a change in the frequency of dielectric maxima with temperature and other parameters.The dielectric constant and transition temperatures are found to increase with increasing Ca substitution. A tunabilty of 71%, much higher than reported in literature for this material, is observed for x = 0.1 i.e for Ba0.9Ca0.1Zr0.25Ti0.75O3. [ABSTRACT FROM AUTHOR]

In this study, we have investigated the structural, interfacial and ferroelectric properties of Sr1-xCaxBi2Ta2O9 thin films grown on Pt/TiO2/SiO2/Si substrates using pulsed-laser-deposition technique. The decrease in lattice parameters with increasing Ca content was attributed to the smaller ionic radius of Ca. Atomic force microscopy shows that the average grain size and surface roughness of the films increases with the incorporation of Ca. Films with x=0.2 exhibited a maximum remanent polarization of ~23.8 μC/cm2 with a coercive field of 175 kV/cm. The higher remanent polarization was attributed to the increased grain size and to the increase in the lattice mismatch between TaO2 and SrO planes. The presence of metallic bismuth at the interface of the film and the substrates was confirmed using XPS depth profile analysis. The current transport property of the thin film capacitors suggests a bulk-limited dc-current conduction mechanism. [ABSTRACT FROM AUTHOR]

Bi-layered ferroelectric thin films of (Sr 0.8 Ba 0.2 )Bi 2 Ta 2 O 9 were grown on Pt/TiO 2 /SiO 2 /Si substrates using the pulsed laser deposition technique. The effect of oxygen pressure and annealing temperature on the structural and electrical properties were studied. The XRD results revealed that the films grown at lower oxygen pressure (100-200 mTorr) and annealed at higher temperature (>800 °C) have the evidence of secondary phase. Whereas, films grown at higher pressure (300 mTorr) and annealed at higher temperature ∼850 °C does not show any secondary phases. Increase in the intensity of optical phonon modes with annealing temperature is attributed to larger grain size at higher annealing temperatures. The films annealed at 800 °C show enhanced ferroelectric properties with remanent polarization (2P r ) of 23.5 μC/cm 2 and coercive field of ∼31 kV/cm. The Films annealed at higher temperature (800°C) have relatively higher dielectric constant with lower dissipation factor (∼0.02). Increased tangential loss with the annealing temperature (> 800 °C) is attributed to the interdiffusion of Bi in to Pt electrode. [ABSTRACT FROM AUTHOR]

Cadmium selenide (CdSe) thin films were deposited on indium tin oxide (ITO) coated glass substrates using pulsed laser deposition (PLD) technique under different growth temperatures. Samples were investigated for their structural, morphological, and optical properties through X-ray diffraction (XRD), atomic force microscopy (AFM), and UV-Vis-NIR spectroscopy. AFM analysis revealed that the surface roughness of the as-grown CdSe thin films increased with the increase in deposition temperature. The optical constants and film thickness were obtained from spectroscopic ellipsometry analysis and are discussed in detail. The optical band gap of the as-grown CdSe thin films, calculated from the Tauc plot analysis, matched with the ellipsometry measurements, with a band gap of ~1.71 eV for a growth temperature range of 150 °C to 400 °C. The CdSe thin films were found to have a refractive index of ~3.0 and extinction coefficient of ~1.0, making it a suitable candidate for photovoltaics. [ABSTRACT FROM AUTHOR]

Multiferroic materials have driven significant research interest due to their promising technological potential. Developing new room‐temperature multiferroics and understanding their fundamental properties are important to reveal unanticipated physical phenomena and potential applications. Here, a new room temperature multiferroic nanocomposite comprised of an ordered ferrimagnetic spinel α‐LiFe5O8 (LFO) and a ferroelectric perovskite BiFeO3 (BFO) is presented. It is observed that lithium (Li)‐doping in BFO favors the formation of LFO spinel as a secondary phase during the synthesis of LixBi1−xFeO3 ceramics. Multimodal functional and chemical imaging methods are used to map the relationship between doping‐induced phase separation and local ferroic properties in both the BFO‐LFO composite ceramics and self‐assembled nanocomposite thin films. The energetics of phase separation in Li doped BFO and the formation of BFO‐LFO composites are supported by first principles calculations. These findings shed light on Li's role in the formation of a functionally important room temperature multiferroic and open a new approach in the synthesis of light element doped nanocomposites for future energy, sensing, and memory applications. [ABSTRACT FROM AUTHOR]

Use of multilayer dielectric thin films provides opportunities to optimize properties for different applications. In this work, the changes in the leakage current in Ba0.8Sr0.2TiO3 thin films upon introduction of ZrO2 layers of different thicknesses are studied. Unusual changes in the leakage current and the transition field with variation in the number and thickness of the ZrO2 layers are observed. Profile of the oxygen concentration across the sample, as determined by x-ray photoelectron spectroscopy, shows that the oxygen diffusion length controls the modulation in the concentration of the charged oxygen vacancies, and hence the depletion layer thicknesses, at the interfaces. A qualitative model for the observed behavior is provided. [ABSTRACT FROM AUTHOR]

Raman spectra of epitaxal BiFeO3 thin films, grown on (111) SrTiO3 substrates, have been studied in temperature range 300-800 K. All four prominent A1-symmetry (81, 138, 170, and 214 cm-1) Raman modes show evolution with the temperature near the Néel temperature (TN), which is interpreted due to spin lattice coupling and it could be also linked with the structural instability originated by octahedral tilting near TN as reported by A. Palewicz et al., Acta Cryst B 63, 537 (2007). As another evidence of spin-phonon coupling, softening of the 214 cm-1 stretching mode is observed near and below the magnetic ordering temperature. [ABSTRACT FROM AUTHOR]

SrBi[sub 2]Ta[sub 2]O[sub 9] (SBT) thin films with different concentrations of Ca at the Sr-site were grown on platinized silicon substrates. A systematic shift of diffraction lines towards higher diffraction angle confirmed the decrease in lattice parameter and attributed to the smaller ionic radii of Ca than for Sr. The grain size of the films was found to be increased upon Ca incorporation in SBT. The dielectric constant of the SBT films was systematically decreased with increasing Ca contents and it was attributed to lower dielectric permittivity of CaBi[sub 2]Ta[sub 2]O[sub 9] system. The ferroelectric properties were gradually increased up to 25% Ca at the Sr site, above which the ferroelectric properties started degrading. The maximum value of remanent polarization (∼23.8 μC/cm[sup 2]) of the films was obtained at 20% Ca substituted SBT. The systematic increase in coercive field was attributed to the higher electronegativity of Ca. The films showed minimal fatigue degradation (<23%) after 10[sup 10] switching cycles. Substitution of Ca (up to 25%) in SBT thin films did not show any pronounced influence on leakage current characteristics. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Non-c-axis-oriented SrBi[sub 2]Nb[sub 2]O[sub 9] (SBN) thin films were grown on Pt/TiO[sub 2]/SiO[sub 2]/Si substrates using the pulsed-laser-deposition technique. X-ray diffraction results confirmed the textured growth of SBN thin films along (115) and (200) orientations. The increase in the value of the dielectric permittivity and decrease in the tangential loss of the films with an increase in annealing temperature were attributed to grain size dependence. SBN thin films annealed at 750 °C exhibited a maximum value of the dielectric constant of ∼346 with a dissipation factor of 0.02. Thin films with certain deposition parameters exhibited the highest remanent polarization (P[sub r]) and coercive field, 25.7 µC/cm² and 198 kV/cm, respectively. There was minimal (<20%) degradation in the switchable polarization (P[sup *] - P[sup ˆ]) after 10[sup 10] switching cycles. At lower field, the leakage current follows ohmic behavior, and at higher field, up to 100 kV/cm, the leakage current density was about 5 × 10[sup -7] A/cm². [ABSTRACT FROM AUTHOR]

A correction to the article "Direct observation of fatigue in epitaxially grown Pb(Zr, Ti)O3 thin films using second harmonic piezoresponse force microscopy," that was published in the 2010 issue is presented.

Films with designed surface morphologies are of great importance for high-performance devices and other applications such as gas sensors and catalysts. Na 2 WO 4 films with various surface morphologies have been fabricated via physical evaporation inside the chamber created by approaching mouth to mouth two alumina boats containing precursors and by covering alumina boat with aluminum foil, respectively. The temperature-dependence Raman investigation reveals red shifting of the Raman peaks with increasing temperature in all cases. The observed Raman shifts are relatively small confirming high stability of the Na 2 WO 4 films within the investigated temperature range. [ABSTRACT FROM AUTHOR]

Abstract: We here report the structural and optical studies of Zn1−x−y Be x Mg y O (0≤ x ≤0.15; 0≤ y ≤0.20) powders and thin films. From the Rietveld refinement of the powder X-ray diffraction (XRD) patterns it was revealed that the value of ‘a’ lattice parameter remains almost unchanged whereas ‘c’ parameter reduces with Be and Mg co-doping in ZnO. The Zn-O bond length also decreases in co-doped samples. Raman studies of the pure ZnO powder showed all the characteristic peaks of the wurtzite hexagonal structure and with (Be, Mg) co-doping new modes appeared which can be attributed to arise as a result of substitution. The XRD of the films prepared from the powders using pulsed laser deposition (PLD) technique exhibited the preferential orientation and with increase in co-doping the (0002) peak also shifts to higher 2θ values suggesting the incorporation of Be/Mg at the Zn-site. From the UV–visible optical transmittance measurement it was noticed that the band gap of the pristine ZnO film is 3.3eV which enhanced up to 4.51eV for Zn0.7Be0.1Mg0.2O film which lies in the solar blind region and is very useful in the realization of deep UV detectors. [ABSTRACT FROM AUTHOR]

Abstract: The PbZr0.53Ti0.47O3(PZT)/CoFe2O4(CFO) layered nanostructures show lowering of dielectric constant and polarization, and an enhanced magnetization with a decrease in temperature from 400K to 100K. The temperature dependence of the real part of the dielectric constant illustrates a step-like behavior, whereas the imaginary part gives a relaxation peak near the step maxima temperature. A slow decrease in the polarization was observed from 300K to 200K, with an eventual collapse of polarization at ~100K, and a complete polarization recovery with heating, these phenomena is reproducible over cycles of experiment. Remanent magnetization of the layered nanostructure was found to be three times higher at 100K than that at room temperature. There is a slow enhancement in remanent (internal) magnetization with lowering of temperature, resulting in slow polarization switch and finally the collapse. The temperature-dependent dielectric, polarization and magnetization were different from the parent layer, indicating a kind of dynamic magneto-electric coupling in the layered nanostructures. [Copyright &y& Elsevier]

MgxZn1−xO (MZO) thin films were deposited from MZO targets as well as sequential deposition of ZnO/MgO multilayers on c-plane Al2O3 substrates using pulsed laser deposition. The total thickness of the films used in this study was ∼300 nm. For multilayer deposition, the thickness of each single ZnO layer was varied in the range of 0.75–2.5 nm followed with the MgO layer thickness of 1 nm. The structural transition from the hexagonal to the cubic phase was observed with the increase in Mg concentration at/above 40% from the single targets. Similar structural change was also observed with the decrease in thickness of single ZnO layer from 2.5 to 0.75 nm in multilayer deposition. The bandgap was increased with increase of Mg contents from 3.3 to 6.2 eV as well as with the change of ZnO sublayer thickness. In both cases it has not been possible to fabricate single-phase stable MZO alloys with a bandgap between 4 and 6 eV. [Copyright &y& Elsevier]

Highly oriented Pb(Zr 0.53 Ti 0.47) 0.90 Sc 0.10 O 3 (PZTS) thin films were deposited on La 0.67 Sr 0.33 MnO 3 (LSMO) buffer layer coated on MgO (100) substrates by following two subsequent laser ablation processes in oxygen atmosphere employing pulse laser deposition technique. The PZTS films were found to grow in tetragonal phase with orientation along (100) plane as inferred from x-ray diffractometry analysis. The structural sensitive symmetric E (LO 2) Raman band softened at elevated temperature along with its intensity continuously decreased until it disappeared in the cubic phase above 350 K. The existence of broad Raman bands at high temperature (>350 K) is attributed to the symmetry forbidden Raman scattering in relaxor cubic phase due to symmetry breaking in nano length scale. The temperature dependent dielectric measurements were performed on metal-ferroelectric-metal capacitors in the frequencies range of 102–106 Hz was observed to be diffused over a wide range of temperature 300–650 K and exhibits high dielectric constant ~5700 at room temperature. An excellent high energy storage density (U re) ~54 J/cm3 with efficiency ~70% was estimated at applied voltage 1.82 MV/cm. High DC breakdown strength, larger dielectric constant and high restored energy density values of our PZTS thin films indicate its usage in high energy storage applications. • T-dependent dielectric studies on Pt/PZTS/LSMO capacitor suggest its relaxor behavior • Excellent high energy storage density ~54 J/cm3 with efficiency ~70% was achieved • The structurally sensitive E (LO 2) Raman band soften at elevated temperature and vanishes in the cubic phase above 350 K [ABSTRACT FROM AUTHOR]

Magnetoelectric multiferroic Properties of BTO/CFO/BTO thin films grown on Pt/TiO 2 /SiO 2 /Si. [Display omitted] • Multiferroic thin films were successfully grown using PLD. • Improved magnetoelectric properties for BTO-CFO-BTO. • Interesting multiferroic and magnetoelectric properties. A magnetoelectric multiferroic bi-phase system with robust ferroelectric and ferro/ferri-magnetism response at room temperature would be ideally suitable for microelectronics, memory devices, and for spintronic applications. BaTiO 3 /CoFe 2 O 4 /BaTiO 3 (BTO/CFO/BTO) heterostructured films were pulsed laser deposition grown on Pt(1 1 1)/TiO 2 /SiO 2 /Si substrates. High quality polycrystalline films were grown by thermal annealing at 750 °C, at an oxygen partial pressure of 100 mTorr for 1 h. Crystal quality and phase formation information was monitored using X-ray diffraction (XRD). XRD confirm the growth of polycrystalline heterostructures and the coexistence of both perovskite BTO and spinel CFO phases in heterostructures. In order to obtain robust magnetoelectric coupling, we studied the tri-layer structure as a representative ferroelectric/ferrimagnetic/ferroelectric system. We report the ferroelectric, leakage current behavior, ferrimagnetic, and frequency dependent ME properties of the films. Ferroelectric BTO and ferrimagnetic inverse spinel CFO nature is also confirmed using the piezoresponse force microscopy and magnetic force microscopy measurements. These nanostructures exhibit high saturation polarization (Ps ∼ 99.86 µC/cm2), saturation magnetization (Ms ∼ 51.48 emu/cm3), and a strong ME coupling coefficient of ∼ 274 mV/cm-Oe with a bias magnetic field of + 90 Oe, anda frequency of 1 kHz revealing them as prospective candidates for multifunctional applications. [ABSTRACT FROM AUTHOR]

Abstract Varying the substrate temperature changes structural and magnetic properties of spinel ferrite Ni 0.65 Zn 0.35 Fe 2 O 4 (NZFO) thin films. X-ray diffraction of films grown at different temperature display only (004) reflections, without any secondary peaks, showing growth orientation along the c-axis. We find an increase in crystalline quality of these thin films with the rise of substrate temperature. The surface topography of thin films grown at different growth temperatures reveal that these films are smooth with low roughness; however, the thin films grown at 800 °C exhibit lowest average and root mean square (rms) roughness among all thin films. We find iron and nickel to be more oxidized (greater Fe3+ and Ni3+ content) in films grown and annealed at 700 °C and 800 °C, compared to those films grown at lower temperatures. The magnetic moment is observed to increase with an increase of substrate temperature and all thin films possess high saturation magnetization and low coercive field at room temperature. Films grown at 800 °C exhibit a ferrimagnetic–paramagnetic phase transition well above room temperature. The observed large magnetizations with soft magnetic behavior in NZFO thin films above room temperature suggest potential applications in memory, spintronics, and multifunctional devices. Highlights • Highly c-axis oriented NZFO thin films were grown by PLD technique. • Varying the substrate temperature changes structural and magnetic properties. • All thin films exhibit high Ms, low Mr and low Hc at room temperature. • The M s is found to be increased with increase of substrate temperature. • Thin films grown at 800 °C exhibit a ferrimagnetic Tc ∼716 (±10) K. [ABSTRACT FROM AUTHOR]

Tin monosulfide (SnS) is promising candidate as a photovoltaic material due to its large tuneable physical properties, which can be achieved by altering the synthesis conditions. Synthesis of pure phase SnS with high crystallinity is really a challenging issue for researchers. The present work mainly focuses on synthesis SnS nanoparticles using a direct reaction approach and manipulate their properties by altering S content. The formation of orthorhombic α-SnS nanoparticles with preferential orientations along the (400) direction has been confirmed by X-ray Diffraction (XRD). Energy Dispersive X-ray analysis (EDX) is used to investigate the elemental composition of all synthesised SnS nanoparticles. SnS nanoparticles of different compositions are deposited on glass substrate using thermal evaporation. The crystal structures of deposited SnS thin films are analysed by XRD. Fourier Transform Infrared (FTIR) spectra indicate the Sn–S bond stretching around 580 - 950 cm−1 including a broad peak around 950 - 1450 cm−1. The Raman spectrum of all SnS thin films shows peaks at 136 ± 2, 190 ± 2, and 231 ± 2 cm−1 assigned as A g mode of SnS. The presence of excess sulphur impacts on the surface morphology of the SnS thin film and is noticeable in FESEM images. UV–Vis–NIR absorbance spectrum revealed that the visible-light absorption of the SnS thin film was significantly high (α ∼105 cm−1). The calculated direct bandgaps of SnS thin films are found to increase (1.63–2.43 eV) with increasing sulphur ratio. • Attempt a new approach to the synthesis of SnS nanoparticles via a direct reaction method. • Strong influence of Sulphur (S) content is noticeable in structural, morphological and vibrational properties in thin film. • The direct optical bandgap of SnS thin films is found to blue shift with increasing S content. • All the term are neccessary to represent the property of thin film. [ABSTRACT FROM AUTHOR]

We have investigated optical and band alignment properties of pulsed laser deposited amorphous thin films of bismuth based monoclinic pyrochlore Bi 2 Zn 2/3− x /3 Nb 4/3−2 x /3 Zr x O 7 (Zr–BZN) where x = 0.4 on quartz and silicon substrates, respectively. The optical parameters, such as complex refractive index ( n − jk ), energy bandgap ( E g ), complex dielectric function ( ε ′ - j ε ″ ), and complex conductivity ( σ ′ - j σ ″ ) and associated dispersion parameters were estimated from the UV–Visible transmission spectra. The analysis of refractive index dispersion confirmed the Wemple–DiDomenico single-effective-oscillator model for the direct inter-band transition. The valence band of Zr–BZN is found to be ∼0.1 eV above that of silicon. The numerical values for conduction band offset Δ E C on silicon and optical bandgap E g were estimated to be ∼2.46 eV and ∼3.46 eV, respectively for Zr–BZN samples. We determined a complete electron band offset dominated type II staggered band lineup of this high- k dielectric/semiconductor heterostructure, where a straight forward spatial confinement of electrons and holes is facilitated. These important results can play critical role and provide key insight for the practical applications of Zr–BZN material, especially in CMOS (complementary metal–oxide–semiconductor) logic and memory devices. [ABSTRACT FROM AUTHOR]

High quality (1 0 0) oriented thin films of (Y 0.9 Bi 0.1 )(Fe 0.5 Cr 0.5 )O 3 [YBFCO] were deposited on (1 0 0) LAO substrates with conducting LNO buffer layer as bottom electrode. YBFCO thin film was found to demonstrate interesting room temperature multiferroic properties where the origin of weak ferroelectricity could be mainly attributed to disordered transition metal ions of unlike spins, and magnetic behavior was ascribed to uncompensated weak ferromagnetism arises due to magnetic cluster state in disordered system. Dielectric anomaly near magnetization reversal temperature ( T irr ) revealed magnetodielectric effect in YBFCO film. In addition, leakage current behavior of the film was explained by trap-controlled space-charge-limited current conduction (SCLC) mechanism. [ABSTRACT FROM AUTHOR]

Rare-earth (Sm) and transition metal (Co) modified polycrystalline BiFeO3 (BFO) thin films have been deposited on Pt/TiO2/SiO2/Si substrate successfully through pulsed laser deposition (PLD) technique. Piezoelectric, leakage current and temperature dependent dielectric and magnetic behaviour were investigated for the films. Typical "butterfly-shaped" loop were observed in BSFCO films with an effective piezoelectric constant (d33) ~94 pm/V at 0.6 MV/cm. High dielectric constant ~900 and low dielectric loss ~0.25 were observed at room temperature. M-H loops have shown relatively high saturation magnetization ~35 emu/cm³ at a maximum field of H ~20 kOe. Enhanced magnetoelectric coupling response is observed under applied magnetic field. The multiferroic, piezoelectric, leakage current behaviours were explored. Such studies should be helpful in designing multiferroic materials based on BSFCO films. [ABSTRACT FROM AUTHOR]

Highlights: [•] High quality thin film of multiferroic BiFeO3 on SrRuO3 is grown by RF Sputtering. [•] The Pt/BFO/SRO structure showed diode like behavior through I–V measurement. [•] Appreciable VOC and JSC were observed with illumination of white light. [•] The photoresponse at zero bias of BFO film showed rapid increase in photocurrent. [•] Application of BFO film for photosensitive capacitor is demonstrated. [ABSTRACT FROM AUTHOR]

Abstract: Piezoresponse Force Microscopy (PFM) technique has been employed to acquire out-of-plane (OPP) piezoresponse images and local piezoelectric hysteresis loop in rhombohedrally distorted Bi1−x Pr x Fe1−y Co y O3 [x =0, 0.05; y =0.05] polycrystalline thin films fabricated via chemical solution deposition method. PFM images revealed that piezoelectric contrast is dependent upon the film composition. Furthermore, negative self-polarization effect was observed in the cobalt substituted BFO film. Well saturated local piezo-hysteresis loops were monitored and an increase was noticed in the piezoelectric coefficient (d 33) value with cobalt doping (25.1pm/V) whereas with Pr co-substitution in BFCO film, the piezoelectric behavior was almost suppressed. Pr and cobalt co-substituted film exhibited the lowest leakage current density. Magnetic behavior (M–H curves) exhibited nearly eight times enhancement in the saturation magnetization values in the Co- and Co–Pr substituted films. The present study provides the different elements’ substitution effect on the local piezoelectric and magnetic properties of BiFeO3 multiferroic thin film. [Copyright &y& Elsevier]

Abstract: Monoclinic Bi2Zn2/3Nb4/3O7 (m-BZN) thin films were deposited by pulsed laser deposition on fused silica substrates at different oxygen pressures. Microwave dielectric and Raman scattering studies were systematically carried out on films that had been annealed at 600 °C after deposition. The dielectric constant of films changes in the range 56–71 due to varying the oxygen pressure during deposition. X-ray diffraction measurements indicate that the BZN thin films deposited at the oxygen pressure of 10 Pa have the best crystalline quality. Atomic force microscopy results show that the surface roughness of the m-BZN film increases with the increase of oxygen pressure. The anomalous change in two higher-frequency Ag modes appearing at 774 and with varying oxygen pressure also suggests a nonequivalent change in the oxygen octahedra around the Nb and Zn and is closely related to the microwave dielectric properties of the thin films. [Copyright &y& Elsevier]