Effect Of Post-annealing Research Articles

Thermal annealing effect on phase evolution, physical properties of DC sputtered copper oxide thin films and transport behavior of ITO/CuO/Al Schottky diodes

Herein, we report on the post-annealing temperature effect on the transport behavior of p-CuO/Al Schottky barrier diodes. In addition, the transformation of phase from Cu4O3 to CuO phase was studied. Copper oxide thin films were grown on soda lime glass substrates, and post-annealing temperature's influence on the films’ structural, chemical, morphological, and electrical characteristics was comprehensively examined. X-ray diffraction study revealed the development of polycrystalline tenorite phase (CuO) on annealing. Raman analysis also confirmed the formation of the tenorite phase (CuO) at higher annealing temperatures (400 °C and 500 °C). XPS study revealed the occurrence of the Cu4O3 phase for room temperature deposited sample and CuO phase at the higher annealing temperature. Using current–voltage analysis, the Chueng model, and the thermoelectric emission model, the Schottky behavior between the metal and semiconductor were investigated. The fabricated diode showed a rectification ratio of 103 at ± 2 V, with the barrier height ranging from 0.84 to 1.12 eV due to different annealing treatments. The attributes of the power law were employed to elucidate space charge-limited conduction and the process of tunneling across the density of interface traps in p-CuO/Al Schottky diodes. This study provides valuable insights into the behavior of the p-CuO/Al Schottky junction, enhancing our understanding of its characteristics.

γ-Ray Irradiation Enables Annealing- and Light-Soaking-Free Solution Processable SnO2 Electron Transport Layer for Inverted Organic Solar Cells.

The electrode buffer layer is crucial for high-performance and stable OSCs, optimizing charge transport and energy level alignment at the interface between the polymer active layer and electrode. Recently, SnO2 has emerged as a promising material for the cathode buffer layer due to its desirable properties, such as high electron mobility, transparency, and stability. Typically, SnO2 nanoparticle layers require a postannealing treatment above 150°C in an air environment to remove the surfactant ligands and obtain high-quality thin films. However, this poses challenges for flexible electronics as flexible substrates can't tolerate temperatures exceeding 100°C. This study presents solution-processable and annealing-free SnO2 nanoparticles by employing y-ray irradiation to disrupt the bonding between surfactant ligands and SnO2 nanoparticles. The SnO2 layer treated with y-ray irradiation is used as an electron transport layer in OSCs based on PTB7-Th:IEICO-4F. Compared to the conventional SnO2 nanoparticles that required high-temperature annealing, the y-SnO2 nanoparticle-based devices exhibit an 11% comparable efficiency without postannealing at a high temperature. Additionally, y-ray treatment has been observed to eliminate the light-soaking effect of SnO2. By eliminating the high-temperature postannealing and light-soaking effect, y-SnO2 nanoparticles offer a promising, cost-effective solution for future flexible solar cells fabricated using roll-to-roll mass processing.

Effect of Ar‐Based Reactive Ion Etching on the Ohmic Contacts in Gallium Oxide Field Effect Transistor

Herein, ultra‐wideband gap semiconductor β‐gallium oxide (β–Ga2O3) over sapphire ( orientation) is investigated for ohmic contact improvement with the help of argon (Ar)‐based reactive ion etching (RIE). Postannealing effects of these contacts over ( orientation) gallium oxide samples are also investigated. The surface defects and oxygen vacancies generated by Ar etching lead to the formation of as‐deposited ohmic contacts with the Ti/Au metal stack. A contact resistance of 10.52 Ω mm with a specific contact resistivity of 2.24 × 10−4 Ω cm2 is achieved with 10 min Ar RIE prior metallization. However, the contacts further degrade when samples are subjected to annealing. The electrical measurements and energy‐dispersive X‐ray spectroscopy elemental mappings at samples after annealing reveal that it is due to the formation of titanium oxide (TiOx) compound which acts as an insulator and concurrent with the out‐diffusion of Ga and in‐diffusion of gold. These results show the impact of anisotropy of gallium oxide over different annealing temperatures. These results and techniques may pave the way for better ohmic contacts for gallium oxide‐based high‐voltage and high‐power applications.

Rapid post-annealing effect on the TiO2-based electrochromic films

The electrochromic (EC) window is a promising energy-saving smart window that can vary between three states: transparent, translucent, and opaque by applying low voltages. One of the potential EC materials is known as titanium dioxide (TiO2) due to its unique chemical and physical properties. Conventional post-annealing has been commonly employed for phase transition in EC thin films, but it suffers from drawbacks such as long treatment time and high energy consumption. Hence, in this study, TiO2 thin films were deposited on indium-doped tin oxide (ITO) and fluoride-doped tin oxide (FTO) glass substrates using a sol-gel spin coating technique, followed by a rapid post-annealing interval of 5 min at temperatures ranging from 300 to 450 °C. The optical, morphological, structural, and EC properties of TiO2 thin films were investigated. The measurement depicted that rapid post-annealing was a cost-effective and time-saving method for realising high-quality TiO2 EC thin films. Hence, this approach reduces the overall fabrication time and minimises energy consumption, rendering it an environmentally friendly process. The successful deployment of TiO2 in EC applications paves the way for integrating EC and photovoltaic technologies in energy-saving window glass applications, considering TiO2 is a crucial element in photovoltaic devices.

Effects of Post-Annealing on the Properties of ZnO:Ga Films with High Transparency (94%) and Low Sheet Resistance (29 Ω/square).

This study presents gallium-doped zinc oxide (ZnO:Ga, GZO) thin films. GZO thin films with both high transparency and low sheet resistance were prepared by RF sputtering and then post-annealed under nitrogen and hydrogen forming gas. With post-annealing at 450 °C, the proposed films with a film thickness of 100 nm showed high transparency (94%), while the sheet resistance of the films was reduced to 29 Ω/square, which was comparable with the performances of commercial indium tin oxide (ITO) samples. Post-annealing under nitrogen and hydrogen forming gas enhanced the films' conductivity while altering the thin-film composition and crystallinity. Nitrogen gas played a role in improving the crystallinity while maintaining the oxygen vacancy of the proposed films, whereas hydrogen did not dope into the thin film, thus maintaining its transparency. Furthermore, hydrogen lowered the resistance of GZO thin films during the annealing process. Then, the detailed mechanisms were discussed. Hydrogen post-annealing helped in the removal of oxygen, therefore increasing the Ga3+ content, which provided extra electrons to lower the resistivity of the films. After the preferable nitrogen/hydrogen forming gas treatment, our proposed films maintained high transparency and low sheet resistance, thus being highly useful for further opto-electronic applications.

Enhanced thermoelectric performance of P-type SnTe thin film through Sr doping and Post-Annealing treatment

Lead-free tin telluride (SnTe) has gained significant attention for its potential use in mid-temperature thermoelectric power generation. In this work, we systematically analyzed the thermoelectric power factor of Sn0.7Sr0.3Te thin films at various post-annealing temperatures through structural, morphological, and thermoelectric property measurements. Our findings show that Sr-doping in the SnTe thin film matrix and post-annealing treatment can significantly enhance the thermoelectric properties by modifying the band structure and introducing an energy-filtering effect at grain boundaries. We achieved a maximum power factor of 29.4 μWm-1K−2 at 523 K for Sn0.7Sr0.3Te thin films post-annealed at 1073 K, which is three times greater than that of pure SnTe. This work demonstrates that Sr-doping and post-annealing effects can tune the band gap, induce band degeneration, and reduce grain size, resulting in a high thermoelectric power factor of the SnTe thin film.

Simultaneously-doping of HfO2 thin films by Ni with sputtering technique and effect of post annealing on structural and electrical properties

This article reports a detailed structural and electrical characterization study of Ni:HfO2 dielectrics grown by rf and dc sputtering and variations in the rapid thermal annealing temperature. Annealing produced obvious changes in the morphological structure of films and XRD confirmed that the crystallite size increased from 1.3 nm to 14.4 nm with the annealing temperature. XPS showed that the amount of non-lattice oxygen decreased owing to the effects of annealing and resistivity. Dc resistivity measurements showed that the lowest sheet resistance of 1.182 × 106 Ω/□ was achieved by as-deposited films and increased to 70.960 Ω/□ with annealing. Structural differences in films due to the effect of annealing caused equivalent circuit models to vary and different resistance values in electrochemical impedance spectrometry. This study illustrates that HfO2 thin films, boosted by doping and rapid thermal annealing, provide a route toward advanced gate oxide stack structures in electronic devices beyond conventional high-dielectric-constant materials.

Effect of post annealing on DC magnetron sputtered tungsten oxide (WO3) thin films for smartwindow applications

Tungsten oxide (WO3) thin films were deposited on Fluorine Doped Tin Oxide (FTO) and Corning Glass (CG) glass substrate by DC magnetron sputtering. The annealing temperature was varied to study its effect on surface morphology, structural, electrochromic (EC), and optical properties and these are investigated by Scanning Electron Microscope (SEM), X-ray Diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, Cyclic voltammetry, and ultraviolet (UV) spectroscopy. From SEM analysis WO3 thin films annealed at 27 °C, 100 °C, 200 °C, and 300 °C were shown to crack free after that cracked film was observed for 400 °C. From the XRD investigation that the WO3 thin films annealed at 27 °C, 100 °C, 200 °C, and 300 °C were amorphous and crystallized at 400 °C. The optical band gap (Eg) of WO3 films was decreased from 2.98 eV to 2.30 eV with an increase in annealed temperature. The coloration efficiency (CE) was observed at 51.26 cm2/C at 300 °C and 35.06 cm2/C at 400 °C and the lowest diffusion coefficient was observed at 5.86 × 10−10 cm2/s at 400 °C. On coloring efficiency, which can be very important in electrochromic (EC) applications, post-annealing has been seen to have a strong influence.

Postannealing Temperature Effects on the Etching Behavior and Field Emission Properties of Cu‐Implanted Diamond

To investigate the postannealing temperature effects on the surface etching behavior and electron field emission (EFE) properties of the Cu‐implanted microcrystalline diamond (MCD) films, they are subjected to furnace annealing in a temperature range of 600–900 °C under N2 atmosphere at a rapid annealing rate. The etching behavior happens when the samples are annealed at 700 °C and above. The EFE performances enhance first and then decrease with the increasing annealing temperature. The optimum EFE property with a low turn‐on field of 6.42 V μm−1 is obtained after the Cu‐implanted MCD film is annealed at 700 °C. The enhancement in EFE properties originates from the presence of nanographitic phase and the formation of electron‐rich Cu nanoparticles, which encourage a higher efficient electron transport. In contrast, the structural studies reveal that when the samples annealed at 800 °C and above, Cu nanoparticles evaporate from the diamond surface and the sp2‐bonded carbon decomposes. Consequently, etch pits appear on the surface of the MCD sample. Moreover, it demonstrates that graphitization is the dominant mechanism of the diamond surface etching behavior and the enhancing of EFE properties.

Post-annealing temperature effects on the structural and optical properties and Cr(VI) removal performance of laser-ablated copper oxide nanoparticles

Post-annealing temperature effects on the structural and optical properties and Cr(VI) removal performance of laser-ablated copper oxide nanoparticles

Effects of post annealing on the microstructure, precipitation behavior, and mechanical property of a (CoCrNi)94Al3Ti3 medium-entropy alloy fabricated by laser powder bed fusion

• The (CoCrNi) 94 Al 3 Ti 3 medium-entropy alloys with different strength-ductility combinations were fabricated by laser powder bed fusion and subsequent annealing processes. • Cr-rich σ-phase precipitates formed after 1073 K and then gradually dissolved at 1373 K, while fine L1 2 coherent precipitates were formed at 1373 K. • Precipitation and grain boundary strengthening both markedly increased owing to the formation of precipitation particles and recrystallization-induced grain refinement after annealing at 1073 K. The additive manufacturing of multi-principal element alloys has remarkable potential for industrial applications. In this study, a (CoCrNi) 94 Al 3 Ti 3 medium-entropy alloy (MEA) with adequate strength-ductility synergy was prepared via laser powder bed fusion. The microstructural evolution, mechanical property, and deformation mechanisms of the MEA were investigated after post annealing for a short period (0.5 h) at a temperature range of 773-1373 K using various microstructural characterization techniques and quantitative analysis. The static recrystallization temperature of the (CoCrNi) 94 Al 3 Ti 3 MEA ranged from 973 to 1073 K. The average grain size first decreased and then increased, while the dislocation density persistently decreased and texture gradually weakened with increasing annealing temperature. Cr-rich σ-phase precipitates formed after 1073 K and then gradually dissolved at 1373 K, while Ni, Al, and Ti elements were aggregated to form a small amount of fine L1 2 coherent precipitates with an average diameter of approximately 70 nm at 1373 K. The evolution of the dislocation density, grain size, and precipitates significantly influenced the propensity of deformation twins and stacking faults, which consequently affected the strain hardening behavior and mechanical properties. The quantitative calculation of strengthening mechanisms showed that dislocation strengthening played a dominant role at annealing temperatures below 1073 K, and it significantly weakened at 1373 K. Precipitation and grain boundary strengthening both markedly increased owing to the formation of precipitation particles and recrystallization-induced grain refinement after annealing at 1073 K.

Growth-control of hexagonal CdS-decorated ZnO nanorod arrays with low-temperature preheating treatment for improved properties and efficient photoelectrochemical applications.

The limitations of oxide semiconductor-based solar cells in achieving high energy conversion efficiencies have prompted incessant research efforts towards the creation of efficient heterostructures. Despite its toxicity, no other semiconducting material can fully replace CdS as a versatile visible light-absorbing sensitizer. Herein, we explore the aptness of preheating treatment in the successive ionic layer adsorption and reaction (SILAR) deposition technique and improve the understanding of the principle and the effects of a controlled growth environment on thus-formed CdS thin films. Single hexagonal phases of nanostructured cadmium sulfide (CdS)-sensitized zinc oxide nanorods arrays (ZnO NRs) have been developed without the support of any complexing agent. The influences of film thickness, cationic solution pH and post-thermal treatment temperature on the characteristics of binary photoelectrodes have been investigated experimentally. Interestingly, the preheating-assisted deposition of CdS, which is rarely applied for the SILAR technique, resulted in improved photoelectrochemical performance similar to the post-annealing effect. The X-ray diffraction pattern revealed that optimized ZnO/CdS thin films were polycrystalline with high crystallinity. Examination of the morphology of the fabricated films via field emission scanning electron microscopy showed that film thickness and medium pH altered the growth mechanism of nanoparticles, thereby changing their particle sizes, which had a significant influence on the film's optical behavior. The effectiveness of CdS as a photosensitizer and the band edge alignment for ZnO/CdS heterostructures were evaluated using ultra-violet visible spectroscopy. Facile electron transfer in the binary system as evidenced in electrochemical impedance spectroscopy Nyquist plots, therefore, promotes higher photoelectrochemical efficiencies from 0.40% to 4.30% under visible light illumination as compared with the pristine ZnO NRs photoanode.

Post-Annealing Effects on Optical Properties of GaAs/AlGaAs Quantum Dots Grown by Droplet Epitaxy

Post-Annealing Effects on Optical Properties of GaAs/AlGaAs Quantum Dots Grown by Droplet Epitaxy

High-temperature post-annealing effect on the device performance of B-doped p-type BaSi2/n-Si heterojunction solar cells grown by molecular beam epitaxy

AstractWe fabricated B-doped p-BaSi2/n-Si heterojunction solar cells by molecular beam epitaxy, and performed post-annealing at 1000 °C in an Ar atmosphere for various annealing durations (t a) in the range 15–300 s. At t a = 15 s, the conversion efficiency (η) under AM 1.5 G illumination was degraded unexpectedly from η = 1.96% for the as-grown sample to η = 0.8%. At t a ≥ 30 s, improvement of the open-circuit voltage (V OC) was obtained. V OC was increased from 0.28 V for the as-grown sample to 0.45 V at t a = 30 s, and the η reached 5.1%. Deep level transient spectroscopy measurement indicated the presence of hole traps coming from point defects near the BaSi2/Si interface. The surface morphology remained almost unchanged at t a ≤ 60 s. However, part of the surface peeled off at t a ≥ 120 s when we separated the attached samples from each other.

Effect of Post-Annealing on Magnetotransport and Magnetic Properties of TaCo2Te2 Single Crystals.

The extreme magnetoresistance (XMR) of some compounds, challenging our understanding of magnetoresistance, is an interesting topic in condensed-matter and materials physics and future device applications. Here, we reported magnetotransport and magnetic properties of the as-grown and post-annealed TaCo2Te2 single crystals. The resistivity evolution with temperature in the two TaCo2Te2 single crystals shows a metallic behavior. Below 50 K, the XMR effect for the two crystals is found, and MR values at 3 K under 9 T are about 3.72 × 103% for the as-grown TaCo2Te2 and 5.71 × 102% for the annealed samples, larger than that of the previous report. The studies on the Hall effect of the two TaCo2Te2 single crystals indicate the multiband feature with high carrier mobilities from a two-band model. Electron and hole concentrations and mobilities of as-grown samples are comparable, while for the annealed sample, the hole concentration and mobility are larger than the electron concentration and mobility. The carrier mobilities for the two TaCo2Te2 single crystals have the same order of magnitude, ∼103 cm2 V-1 s-1. The XMR effect may be from high carrier mobilities. Magnetization of the as-grown TaCo2Te2 decreases with increasing temperature, and a weaker magnetic transition at ∼150 K is observed. The annealed TaCo2Te2 shows no magnetic transition and just a paramagnetic behavior with rising temperature. These results indicate that defects/deficiencies may play an important role in magnetotransport and magnetic properties of the two TaCo2Te2 single crystals. These results are helpful in deeply understanding the XMR mechanism and magnetic properties in TaCo2Te2 and offer a way to study the magnetic properties of the XMR Co-Te system.

Post-annealing Effect on Surface Wettability by Electron Beam Evaporated Ag/In2O3 Thin Films

Post-annealing Effect on Surface Wettability by Electron Beam Evaporated Ag/In2O3 Thin Films

Effect of Post-Annealing on Barrier Modulations in Pd/IGZO/SiO2/p+-Si Memristors.

In this article, we study the post-annealing effect on the synaptic characteristics in Pd/IGZO/SiO2/p+-Si memristor devices. The O-H bond in IGZO films affects the switching characteristics that can be controlled by the annealing process. We propose a switching model based on using a native oxide as the Schottky barrier. The barrier height is extracted by the conduction mechanism of thermionic emission in samples with different annealing temperatures. Additionally, the change in conductance is explained by an energy band diagram including trap models. The activation energy is obtained by the depression curve of the samples with different annealing temperatures to better understand the switching mechanism. Moreover, our results reveal that the annealing temperature and retention can affect the linearity of potentiation and depression. Finally, we investigate the effect of the annealing temperature on the recognition rate of MNIST in the proposed neural network.

Annealing effects on epitaxial (K,Na)NbO3 thin films grown on Si substrates

Epitaxial (K,Na)NbO3 (KNN) thin films were deposited on (001)SrRuO3/Pt/ZrO2/Si substrates by RF magnetron sputtering, and post-annealing effects on the as-deposited epitaxial KNN thin films were investigated. According to the findings, by annealing, the crystal system of these thin films changes from a tetragonal to an orthorhombic system because of the release of internal stress. The asymmetry of polarization–electric field hysteresis loops along the electric field changes from a positive to a negative side by annealing. This means that stable spontaneous polarization P s changes from the upward to downward direction with an increase in the number of A-site vacancies. In addition, the displacement–electric field curves of epitaxial KNN/Si unimorph cantilevers exhibit asymmetric behaviors. A relatively high converse piezoelectric coefficient ∣e 31,f ∣ = 6.4 C m−2 is obtained for 5 h annealed epitaxial KNN thin films.

Post-annealing effect of thin platinum oxide film on tin oxide film for an application enhancing gas sensitivity

A thin platinum oxide film was stacked on a tin oxide film, a well-known gas-sensing semiconductor, to improve its gas sensitivity. The response property to ethanol gas was enhanced by about three times by the stacking annealed at 600 °C. Post-annealing, platinum oxide was reduced to platinum and tin oxide was in a polycrystalline state. The results indicate that applying platinum oxide is effective in improving sensitivity when annealing at a high temperature of 600 °C is required for the fabrication of gas sensors.

Improved Photovoltaic Properties of Nano-Flake-Based Mesoporous Dip- SILAR Prepared BiOI Electrochemical Cell By Tuning Post-Annealing Treatment Time at 100°C

Background: This research article reports on the post-annealing treatment time effect on the dip-successive ionic layer adsorption and reaction (SILAR) prepared nano-flake-based mesoporous BiOI electrochemical cell's photovoltaic properties. Objective: Our study clarifies that the post-annealing time has a great impact on the photovoltaic behavior and the nano-flake morphology. Methods: At 100°C for 90 mins of post-annealing treatment conditions, the surface morphology converted into a connected uniform crystallized flaky structure, which improves the effective surface area and reduces the BiOI/electrolyte charge transfer resistance confirmed via electrochemical impedance spectroscopy (EIS) analysis. Therefore, the maximum photovoltaic properties (short-circuit current density, Jsc = 1.83mA/cm2, open-circuit voltage, Voc = 0.48V and efficiency = 0.28%) have been observed. However, without annealing and beyond 90 mins of post-annealing time, the film quality and crystallinity decreased as a consequence of photovoltaic properties degradation. Results and Conclusion: Our investigation finding is that 90 mins is the optimal post-annealing treatment duration for the dip-SILAR prepared nano-flake-based mesoporous BiOI electrochemical photovoltaic cell at 100°C post-annealing temperature.