Browse
Submit Data
Databases
API
Help

Dataset Information

26 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Novel Physical Vapor Deposition Approach to Hybrid Perovskites: Growth of MAPbI₃ Thin Films by RF-Magnetron Sputtering.

ABSTRACT: Solution-based methods represent the most widespread approach used to deposit hybrid organic-inorganic perovskite films for low-cost but efficient solar cells. However, solution-process techniques offer limited control over film morphology and crystallinity, and most importantly do not allow sequential film deposition to produce perovskite-perovskite heterostructures. Here the successful deposition of CH₃NH₃PbI₃ (MAPI) thin films by RF-magnetron sputtering is reported, an industry-tested method to grow large area devices with precisely controlled stoichiometry. MAPI films are grown starting from a single-target made of CH₃NH₃I (MAI) and PbI₂. Films are single-phase, with a barely detectable content of unreacted PbI₂, full surface coverage and thickness ranging from less than 200 nm to more than 3 μm. Light absorption and emission properties of the deposited films are comparable to as-grown solution-processed MAPI films. The development of vapor-phase deposition methods is of interest to advance perovskite photovoltaic devices with the possibility of fabricating perovskite multijunction solar cells or multicolor bright light-emitting devices in the whole visible spectrum.

SUBMITTER: Bonomi S

PROVIDER: S-EPMC6193984 | biostudies-literature |

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Similar Datasets

Combined magnetron sputtering and pulsed laser deposition of TiO 2 and BFCO thin films.

Project description:We report the successful demonstration of a hybrid system that combines pulsed laser deposition (PLD) and magnetron sputtering (MS) to deposit high quality thin films. The PLD and MS simultaneously use the same target, leading to an enhanced deposition rate. The performance of this technique is demonstrated through the deposition of titanium dioxide and bismuth-based perovskite oxide Bi2FeCrO6 (BFCO) thin films on Si(100) and LaAlO3 (LAO) (100). These specific oxides were chosen due to their functionalities, such as multiferroic and photovoltaic properties (BFCO) and photocatalysis (TiO2). We compare films deposited by conventional PLD, MS and PLD combined with MS, and show that under all conditions the latter technique offers an increased deposition rate (+50%) and produces films denser (+20%) than those produced by MS or PLD alone, and without the large clusters found in the PLD-deposited films. Under optimized conditions, the hybrid technique produces films that are two times smoother than either technique alone.

| S-EPMC5451404 | biostudies-literature

Reset First Resistive Switching in Ni1-xO Thin Films as Charge Transfer Insulator Deposited by Reactive RF Magnetron Sputtering.

Project description:Reset-first resistive random access memory (RRAM) devices were demonstrated for off-stoichiometric Ni1-xO thin films deposited using reactive sputtering with a high oxygen partial pressure. The Ni1-xO based RRAM devices exhibited both unipolar and bipolar resistive switching characteristics without an electroforming step. Auger electron spectroscopy showed nickel deficiency in the Ni1-xO films, and X-ray photoemission spectroscopy showed that the Ni3+ valence state in the Ni1-xO films increased with increasing oxygen partial pressure. Conductive atomic force microscopy showed that the conductivity of the Ni1-xO films increased with increasing oxygen partial pressure during deposition, possibly contributing to the reset-first switching of the Ni1-xO films.

| S-EPMC9268175 | biostudies-literature

Radio Frequency Magnetron Sputtering Deposition of TiO2 Thin Films and Their Perovskite Solar Cell Applications.

Project description:In this work, we report a physical deposition based, compact (cp) layer synthesis for planar heterojunction perovskite solar cells. Typical solution-based synthesis of cp layer for perovskite solar cells involves low-quality of thin films, high-temperature annealing, non-flexible devices, limitation of large-scale production and that the effects of the cp layer on carrier transport have not been fully understood. In this research, using radio frequency magnetron sputtering (RFMS), TiO2 cp layers were fabricated and the thickness could be controlled by deposition time; CH3NH3PbI3 films were prepared by evaporation &immersion (E &I) method, in which PbI2 films made by thermal evaporation technique were immersed in CH3NH3I solution. The devices exhibit power conversion efficiency (PCE) of 12.1% and the photovoltaic performance can maintain 77% of its initial PCE after 1440 h. The method developed in this study has the capability of fabricating large active area devices (40 × 40 mm(2)) showing a promising PCE of 4.8%. Low temperature and flexible devices were realized and a PCE of 8.9% was obtained on the PET/ITO substrates. These approaches could be used in thin film based solar cells which require high-quality films leading to reduced fabrication cost and improved device performance.

| S-EPMC4668551 | biostudies-literature

HRTEM Microstructural Characterization of β-WO3 Thin Films Deposited by Reactive RF Magnetron Sputtering.

Project description:Though tungsten trioxide (WO3) in bulk, nanosphere, and thin film samples has been extensively studied, few studies have been dedicated to the crystallographic structure of WO3 thin films. In this work, the evolution from amorphous WO3 thin films to crystalline WO3 thin films is discussed. WO3 thin films were fabricated on silicon substrates (Si/SiO2) by RF reactive magnetron sputtering. Once a thin film was deposited, two successive annealing treatments were made: an initial annealing at 400 °C for 6 h was followed by a second annealing at 350 °C for 1 h. Film characterization was carried out by X-ray diffraction (XRD), high-resolution electron transmission microscopy (HRTEM), scanning electron microscopy (SEM), and atomic force microscopy (AFM) techniques. The β-WO3 final phase grew in form of columnar crystals and its growth plane was determined by HRTEM.

| S-EPMC5459164 | biostudies-other

Optically Active TiO2:Er Thin Films Deposited by Magnetron Sputtering.

Project description:Titanium dioxide photoanodes for hydrogen generation suffer from a profound mismatch between the optical absorption of TiO2 and the solar spectrum. To solve the problem of low solar-to-chemical efficiency, optically active materials are proposed. In this work, TiO2 thin films containing erbium were deposited by radio frequency RF magnetron sputtering under ultrahigh vacuum conditions UHV. Morphology, structural, optical and electronic properties were studied. TiO2:Er thin films are homogenous, with uniform distribution of Er ions and high transparency over the visible VIS range of the light spectrum. However, a profound 0.4 eV blue shift of the fundamental absorption edge with respect to undoped TiO2 was observed, which can be attributed either to the size effect due to amorphization of TiO2 host or to the onset of precipitation of Er2Ti2O7 nanocrystals. Near-infrared NIR to VIS up-conversion is demonstrated upon excitation at 980 nm, while strong green photoluminescence at 525 and 550 nm occurs upon photon absorption at 488 nm.

| S-EPMC8348420 | biostudies-literature

First Proof-of-Principle of Inorganic Lead Halide Perovskites Deposition by Magnetron-Sputtering.

Project description:The present work reports the application of RF-magnetron sputtering technique to realize CsPbBr 3 70 nm thick films on glass substrate by means of a one-step procedure. The obtained films show highly uniform surface morphology and homogeneous thickness as evidenced by AFM and SEM investigations. XRD measurements demonstrate the presence of two phases: a dominant orthorhombic CsPbBr 3 and a subordinate CsPb 2 Br 5 . Finally, XPS data reveals surface bromine depletion respect to the stoichiometrical CsPbBr 3 composition, nevertheless photoluminescence spectroscopy results confirm the formation of a highly luminescent film. These preliminary results demonstrate that our approach could be of great relevance for easy fabrication of large area perovskite thin films. Future developments, based on this approach, may include the realization of multijunction solar cells and multicolor light emitting devices.

| S-EPMC7022632 | biostudies-literature

Deposition of Visible Light Active Photocatalytic Bismuth Molybdate Thin Films by Reactive Magnetron Sputtering.

Project description:Bismuth molybdate thin films were deposited by reactive magnetron co-sputtering from two metallic targets in an argon/oxygen atmosphere, reportedly for the first time. Energy dispersive X-ray spectroscopy (EDX) analysis showed that the ratio of bismuth to molybdenum in the coatings can be effectively controlled by varying the power applied to each target. Deposited coatings were annealed in air at 673 K for 30 min. The crystalline structure was assessed by means of Raman spectroscopy and X-ray diffraction (XRD). Oxidation state information was obtained by X-ray photoelectron spectroscopy (XPS). Photodegradation of organic dyes methylene blue and rhodamine B was used for evaluation of the photocatalytic properties of the coatings under a visible light source. The photocatalytic properties of the deposited coatings were then compared to a sample of commercial titanium dioxide-based photocatalytic product. The repeatability of the dye degradation reactions and photocatalytic coating reusability are discussed. It was found that coatings with a Bi:Mo ratio of approximately 2:1 exhibited the highest photocatalytic activity of the coatings studied; its efficacy in dye photodegradation significantly outperformed a sample of commercial photocatalytic coating.

| S-EPMC5456504 | biostudies-other

Formation of Thin NiGe Films by Magnetron Sputtering and Flash Lamp Annealing.

Project description:The nickel monogermanide (NiGe) phase is known for its electrical properties such as low ohmic and low contact resistance in group-IV-based electronics. In this work, thin films of nickel germanides (Ni-Ge) were formed by magnetron sputtering followed by flash lamp annealing (FLA). The formation of NiGe was investigated on three types of substrates: on amorphous (a-Ge) as well as polycrystalline Ge (poly-Ge) and on monocrystalline (100)-Ge (c-Ge) wafers. Substrate and NiGe structure characterization was performed by Raman, TEM, and XRD analyses. Hall Effect and four-point-probe measurements were used to characterize the films electrically. NiGe layers were successfully formed on different Ge substrates using 3-ms FLA. Electrical as well as XRD and TEM measurements are revealing the formation of Ni-rich hexagonal and cubic phases at lower temperatures accompanied by the formation of the low-resistivity orthorhombic NiGe phase. At higher annealing temperatures, Ni-rich phases are transforming into NiGe, as long as the supply of Ge is ensured. NiGe layer formation on a-Ge is accompanied by metal-induced crystallization and its elevated electrical resistivity compared with that of poly-Ge and c-Ge substrates. Specific resistivities for 30 nm Ni on Ge were determined to be 13.5 ??·cm for poly-Ge, 14.6 ??·cm for c-Ge, and 20.1 ??·cm for a-Ge.

| S-EPMC7221967 | biostudies-literature

Superparamagnetic state in La0.7Sr0.3MnO3 thin films obtained by rf-sputtering.

Project description:A novel superparamagnetic state has been observed in high quality La0.7Sr0.3MnO3 (LSMO) thin films directly grown by rf-sputtering on SiOx/Si(100) substrates. The films are nanostructured without grain boundaries, constituted by locally epitaxial nanoregions grown layer-by-layer with out-of-plane (012) preferential orientation, induced by the constrain of the native silicon oxide. Low magnetic field ZFC-FC magnetization curves show a cross-over from superparamagnetic to ferromagnetic state dependent of the thickness. The thicker film (140 nm) exhibits typical ferromagnetic order. The thinner films (40 and 60 nm) exhibit superparamagnetic behavior attributed to interacting ferromagnetic monodomain nanoregions with critical size, random in-plane oriented, where the inter-monodomain boundaries with surface spin-glass structure regulate the blocking of magnetization depending on the magnetic field intensity. M(H) hysteresis loops showed noticeable coercive fields in all samples, larger than those reported for LSMO. Such properties of half-metal LSMO film foresee potential integration in new Si-technology nanodevices in Spintronics.

| S-EPMC7018749 | biostudies-literature

Resistive Switching Characteristics of Li-Doped ZnO Thin Films Based on Magnetron Sputtering.

Project description:A kind of devices Pt/Ag/ZnO:Li/Pt/Ti with high resistive switching behaviors were prepared on a SiO2/Si substrate by using magnetron sputtering method and mask technology, composed of a bottom electrode (BE) of Pt/Ti, a resistive switching layer of ZnO:Li thin film and a top electrode (TE) of Pt/Ag. To determine the crystal lattice structure and the Li-doped concentration in the resulted ZnO thin films, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) tests were carried out. Resistive switching behaviors of the devices with different thicknesses of Li-doped ZnO thin films were studied at different set and reset voltages based on analog and digital resistive switching characteristics. At room temperature, the fabricated devices represent stable bipolar resistive switching behaviors with a low set voltage, a high switching current ratio and a long retention up to 104 s. In addition, the device can sustain an excellent endurance more than 103 cycles at an applied pulse voltage. The mechanism on how the thicknesses of the Li-doped ZnO thin films affect the resistive switching behaviors was investigated by installing conduction mechanism models. This study provides a new strategy for fabricating the resistive random access memory (ReRAM) device used in practice.

| S-EPMC6515171 | biostudies-literature