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In this study, we compare the performance of ferroelectric memristor devices based on the fabrication method for the top electrode, focusing on atomic layer deposition (ALD) and physical vapor deposition techniques. We investigate the effects of these methods on the formation of the orthorhombic phase (o-phase) in HfAlOx (HAO) ferroelectric films, which is crucial for ferroelectric properties. The devices were fabricated with HAO films doped with 3.4% aluminum, followed by rapid thermal annealing at 700 °C. Our results demonstrate that the atomic layer deposition process forms a TiOxNy capping layer at the interface between the HAO film and the TiN top electrode, which promotes the o-phase formation. This capping layer effect leads to enhanced polarization characteristics, as evidenced by higher remnant polarization and tunneling electroresistance (TER) in the ALD-fabricated devices. The ALD method also results in a better interfacial layer condition, confirmed by a lower interfacial non-ferroelectric capacitance (Ci). Characterization techniques, including transmission electron microscopy, energy dispersive x-ray spectroscopy, and x-ray diffraction. These structural advantages contribute to enhanced electrical performance, demonstrating neuromorphic applications. Here, our study highlights the significant impact of the ALD deposition method on enhancing the ferroelectric properties and overall performance of ferroelectric memristor devices, making it a promising approach for advanced memory and neuromorphic computing applications. [ABSTRACT FROM AUTHOR]

Laser annealing was employed to trigger the solid-state reaction of a thin Co film (2.5 nm) with undoped Si. A metastable disilicide layer was obtained after one laser pulse close to the melt threshold. Its diffraction pattern, relaxed lattice parameter, and residual resisitivity are consistent with the formation of the defective CsCl structure. The CoSi2 phase was found after prolonging the thermal treatment with additional pulses or rapid thermal annealing. Because CoSi is skipped in the phase sequence, CoSi2 layers are more uniform in thickness, have an increased superconductivity and a reduced formation temperature. This approach is compatible with the SALICIDE process and can be used to form smooth contacts in superconducting or regular transistors. [ABSTRACT FROM AUTHOR]

In this contribution, we investigate the formation and dissociation of boron–hydrogen (BH) pairs in crystalline silicon under thermal equilibrium conditions. Our samples span doping concentrations of nearly two orders of magnitude and are passivated with a layer stack consisting of thin aluminum oxide and hydrogen-rich silicon nitride (Al 2 O 3 /SiN x :H). This layer stack acts as a hydrogen source during a following rapid thermal annealing. We characterize the samples using low-temperature Fourier-transform infrared spectroscopy and four-point-probe resistivity measurements. Our findings show that the proportion of hydrogen atoms initially bound to boron (BH pairs) rises with increasing boron concentration. Upon isothermal dark annealing at (163 ± 2) °C, hydrogen present in molecular form, H 2 , dissociates at a rate directly proportional to the concentration of boron atoms, ∝ [ B − ], leading to the formation of BH pairs. With prolonged annealing, an unknown hydrogen complex is formed at a rate that is inversely proportional to the square of the boron concentration, ∝ 1/[B − ] 2 , resulting in the disappearance of BH pairs. Based on experimental observations, we derive a kinetic model in which we describe the formation of the unknown complex through neutral hydrogen H 0 binding to a sink. Additionally, we investigate the temperature dependence of the reaction rates and find that the H 2 dissociation process has an activation energy of (1.11 ± 0.05) eV, which is in close agreement with theoretical predictions. [ABSTRACT FROM AUTHOR]

Rare-earth iron garnets (REIGs) are the benchmark systems for magnonics, including the longitudinal spin Seebeck effect (LSSE). While most research has focused on single-crystalline REIGs on complimentary garnet substrates, moving to more, cost-effective complementary metal-oxide semiconductor (CMOS)-compatible substrates is important to integrate REIG thin films with existing technology. In this regard, we grow a 130 nm-thick polycrystalline gadolinium iron garnet (GdIG) film on the Si/SiO2 substrate and investigate the temperature-dependent LSSE. Interestingly, the polycrystalline GdIG film exhibits perpendicular magnetic anisotropy (PMA) at room temperature which is induced by tensile in-plane (IP)-strain originating from the thermal-expansion mismatch between the GdIG film and the substrate during rapid thermal annealing. Further, a spin-reorientation transition from the out-of-plane IP direction below TS = 180 K is observed. Additionally, the film reveals a magnetic compensation temperature, T Comp , of ≈240 K. The LSSE voltage not only demonstrates a sign-inversion around T Comp , but also shows noticeable changes around T S. As compared to a single-crystalline GdIG film, the lower LSSE voltage for the polycrystalline GdIG is attributed to the higher effective magnetic anisotropy and enhanced magnon scattering at the grain boundaries. Our study not only paves the way for the cost-effective growth of CMOS-compatible REIG-based systems with PMA for magnonic memory and information processing applications, but also highlights the fact that the spincaloritronic and spin-insulatronic properties of the polycrystalline REIGs follow those of their single-crystalline counterparts with reduced spin-to-charge conversion efficiency through LSSE which can be tuned further by controlling the average gran size and interface engineering. [ABSTRACT FROM AUTHOR]

Al0.85Sc0.15N thin films, about 920 nm thick, have been deposited on the Si (001) substrate by reactive magnetron sputtering at 600 °C. X-ray diffraction and pole-figure measurements revealed [0002]-oriented texture structures of the nitride films without any phase separations before and after cyclic annealing at 600–900 °C for up to 48 min. Cross-sectional studies by transmission electron microscopy and energy dispersive x-ray analysis revealed an intermediate Al0.85Sc0.15N layer of ∼24.6 nm thick with smaller grains and tilted [0002]-orientations compared to its overlayer, i.e., a nucleation layer (NL), on the Si substrate. After annealing, apparent morphological changes have been observed at the near-interface regions, including the NL, the NL/Si interface, and the Si substrate, rather than in the Al0.85Sc0.15N overlay. Undesired oxygen has been observed in the nitride film and its composition increased during post-growth thermal annealing without forming oxides. These observations shed new light on crystal growth and post-growth thermal annealing of AlScN toward their high-performance piezoelectric applications. [ABSTRACT FROM AUTHOR]

Most semiconductors exhibit a saturation of free carriers when heavily doped with extrinsic dopants. This carrier saturation or "doping limit" is known to be related to the formation of native compensating defects, which, in turn, depends on the energy positions of their conduction band minimum and valence band maximum. Here, we carried out a systematic study on the n-type doping limit of GaAs via ion implantation and showed that this doping limitation can be alleviated by the transient process of pulsed laser melting (PLM). For n-type doping, both group VI (S) and amphoteric group IV (Si and Ge) dopants were implanted in GaAs. For comparison, p-type doping was also studied using Zn as the acceptor. Implanted dopants were activated by the PLM method, and the results are compared to rapid thermal annealing (RTA). Our results reveal that for all n-type dopants, while implantation followed by the RTA results in a similar saturation electron concentration of 2–3 × 1018 cm−3, the transient PLM process is capable of trapping high concentration of dopants in the substitutional site, giving rise to a carrier concentration of >1019 cm−3, exceeding the doping limit of GaAs. However, due to scatterings from point defects generated during PLM, the mobility of n-type GaAs after PLM is low (∼80–260 cm2/V s). Subsequent RTA after PLM (PLM + RTA) is able to remove these point defects and recover the mobility to ∼1000–2000 cm2/V s. The carrier concentrations of these PLM + RTA samples are reduced but are still a factor of 3 higher than RTA only GaAs. This can be understood as the dopants are already incorporated in the substitutional site after PLM; they are less likely to be "deactivated" by subsequent RTA. This work is significant to the understanding of doping mechanisms in semiconductors and provides a means for device applications, which require materials with ultra-high doping. [ABSTRACT FROM AUTHOR]

We have attained low leakage current, low interfacial traps, and low border traps by effectively passivating both p- and n-In0.53Ga0.47As (InGaAs) surfaces using the same gate dielectrics of ultra-high-vacuum deposited Al2O3/Y2O3. Gate leakage currents below 2 × 10−7 A/cm2 at gate fields of ±4 MV/cm were obtained after 800 °C rapid thermal annealing, demonstrating the intactness of the interface and heterostructure. Negligibly small frequency dispersions in the capacitance–voltage (C–V) characteristics of p- and n-type metal-oxide-semiconductor capacitors (MOSCAPs) were obtained from accumulation, flatband, to depletion as measured from 300 K to 77 K, indicative of low border and interfacial trap density; the C–V frequency dispersions in the accumulation region are 1.5%/dec (300 K) and 0.19%/dec (77 K) for p-InGaAs, and 2.2%/dec (300 K) and 0.97%/dec (77 K) for n-InGaAs. Very low interfacial trap densities (Dit's) of (1.7–3.2) × 1011 eV−1cm−2 and (6.7–8.5) × 1010 eV−1cm−2, as extracted from the conductance method, were achieved on p- and n-InGaAs MOSCAPs, respectively. [ABSTRACT FROM AUTHOR]

This work presents the effect of the rapid thermal annealing (RTA) process on the performance of Ti/MoOx/Pt resistive random access memory (RRAM). Compared with the device without RTA treatment, the device processed in vacuum RTA (300 ℃,80 s) exhibits better resistance switching (RS) characteristics, including smaller forming voltage (Vf = 5.7 V) and set voltage (Vset = 1.41 V), stable high-resistance state (coefficient of variation = 5.91%) and 100 times storage window. This may be attributed to changes in oxygen vacancies (VO) content. The X-ray diffraction (XRD) analysis results indicate that the prepared MoOx thin films are all amorphous. X-ray photoelectron spectroscopic (XPS) analysis results indicate that vacuum RTA treatment increases the VO content in the MoOx dielectric layer, which may make it easier for thick conductive filaments to form. This leads to a reduction in the Vf and Vset, while also establishing a relatively fixed fracture position for conductive filaments, thereby achieving a stable high-resistance state. XPS depth profiling results of Device B before and after applying positive voltage indicate the formation of TiOx layer at the interface and the increase of VO in the MoOx dielectric layer (33.90% → 55.37%), which may indicate the establishment process of VO conductive filaments in the device. In addition, we have explored synaptic applications of RRAM devices with this structure and simulated a range of synaptic behaviors, demonstrating the potential of MoOx-based RRAM as an artificial synaptic device in neural morphology computing systems. [ABSTRACT FROM AUTHOR]

The examination on β-FeSi2 thin films prepared via facing-target sputtering onto Si(111), subjected to rapid thermal annealing under varying temperatures of 200–800 °C, revealed numerous changes in the film's physical traits. The energy-dispersive X-ray spectroscope findings corroborate the anticipated atomic composition, displaying strong Si and small Fe peaks, including C and Al impurities. The Fe/Si proportions barely changed after rapid annealing. Under 200 °C and 400 °C, the X-ray diffractometer spectra indicated that orientation (202/220) and (404/440) of β-FeSi2 were improved by rapid annealing, while surface morphology also revealed gradual enhancement in grain structure and roughness. Temperatures of over 600 °C induced recrystallization of the films, resulting in the reduced orientation peak's intensities, grain compression, and coarsening. These changes caused the air gap to collapse, turning the film's surface hydrophilic with contact angles of 86.15° at 600 °C and 63.00° at 800 °C. In contrast, the films retained hydrophobicity with contact angles of 93.40° at 200 °C and 91.20° at 400 °C compared to the as-prepared films of 96.75°. The hardness and Young's modulus improved with rising temperature to 15.2 GPa and 225.8 GPa at maximum. This has ramifications for their prospective use in self-cleaning and hard-coating applications. [ABSTRACT FROM AUTHOR]

Rapid thermal annealing (RTA) has been widely used in semiconductor device processing. However, the rise time of RTA, limited to the millisecond (ms) range, is unsuitable for advanced nanometer-scale electronic devices. Using sub-energy bandgap (EG) 532 nm ultra-fast 15 nanosecond (ns) pulsed laser annealing, a record-high dielectric constant (high-κ) of 67.8 and a capacitance density of 75 fF/μm2 at −0.2 V were achieved in Ni/ZrO2/TiN capacitors. According to heat source and diffusion equations, the surface temperature of TiN can reach as high as 870 °C at a laser energy density of 16.2 J/cm2, effectively annealing the ZrO2 material. These record-breaking results are enabled by a novel annealing method—the surface plasma effect generated on the TiN metal. This is because the 2.3 eV (532 nm) pulsed laser energy is significantly lower than the 5.0–5.8 eV energy bandgap (EG) of ZrO2, making it unabsorbable by the ZrO2 dielectric. X-ray diffraction analysis reveals that the large κ value and capacitance density are attributed to the enhanced crystallinity of the cubic-phase ZrO2, which is improved through laser annealing. This advancement is critical for monolithic three-dimensional device integration in the backend of advanced integrated circuits. [ABSTRACT FROM AUTHOR]

The examination on β-FeSi2 thin films prepared via facing-target sputtering onto Si(111), subjected to rapid thermal annealing under varying temperatures of 200–800 °C, revealed numerous changes in the film's physical traits. The energy-dispersive X-ray spectroscope findings corroborate the anticipated atomic composition, displaying strong Si and small Fe peaks, including C and Al impurities. The Fe/Si proportions barely changed after rapid annealing. Under 200 °C and 400 °C, the X-ray diffractometer spectra indicated that orientation (202/220) and (404/440) of β-FeSi2 were improved by rapid annealing, while surface morphology also revealed gradual enhancement in grain structure and roughness. Temperatures of over 600 °C induced recrystallization of the films, resulting in the reduced orientation peak's intensities, grain compression, and coarsening. These changes caused the air gap to collapse, turning the film's surface hydrophilic with contact angles of 86.15° at 600 °C and 63.00° at 800 °C. In contrast, the films retained hydrophobicity with contact angles of 93.40° at 200 °C and 91.20° at 400 °C compared to the as-prepared films of 96.75°. The hardness and Young's modulus improved with rising temperature to 15.2 GPa and 225.8 GPa at maximum. This has ramifications for their prospective use in self-cleaning and hard-coating applications. [ABSTRACT FROM AUTHOR]

Biomass is considered as a desirable carbon source due to its abundance, low cost, environmental friendliness and sustainability. The traditional preparation methods of biomass-derived carbon materials, typically in-furnace pyrolysis, involve tedious and energy-consuming processes and require harsh operation conditions. In contrast, laser-induced carbonization is a facile, environmentally friendly and high-efficiency technique that can create an instantaneous thermal shock process for the rapid conversion of biomass into carbon, enabling it to more easily possess unique active sites that play powerful roles in energy storage and conversion applications. Besides, the microstructure and composition of laser-induced biomass-derived carbon materials (LIBCs) can be precisely regulated by adjusting precursor types and laser processing parameters. In this review, the current developments on LIBCs are elaborated. The laser-induced carbonization mechanism is first introduced, and the effects of laser parameters including laser power, scanning speed, laser spot defocus, and atmosphere on the carbonization process are discussed. A special focus is put on the functionalization treatment of LIBCs, including the doping of heteroatoms as well as the incorporation of metals or metal compounds. The applications of LIBCs in the fields of micro-supercapacitors, batteries, electrocatalysis, sensors, and so on are highlighted. Finally, the current challenges and future prospects of LIBCs are discussed. [ABSTRACT FROM AUTHOR]

NiOx is a p-type semiconductor with excellent stability, which makes it interesting for a wide range of applications. Broadband photodetectors with high responsivity (R) were fabricated by depositing r.f.-sputtered NiOx layers on n-Si at room temperature (RT), 50 °C and 100 °C. In self-powered mode the RT diodes have R between 0.95 and 0.39 A/W for wavelengths between 365 and 635 nm, while at a reverse bias of −4 V, the responsivity increases to values between 22 A/W and 10.7 A/W for wavelengths in the same range. The increase of the deposition temperature leads to a decrease of R but also to a smaller reverse dark current. Thus, the 100 °C photodiodes might be more appropriate for applications where high responsivity is required, because of their smaller power consumption compared to the RT diodes. In addition, it was found that the increase of the deposition temperature leads to an increase of the diodes' series resistance and the resistivity of NiOx. The effect of Rapid Thermal Annealing (RTA) on the properties of the photodiodes was studied. Annealing at 550 °C for 6 min leads to much higher responsivity compared to R of diodes with as-deposited NiOx. However, a disadvantage of the annealed diode is that the reverse current depends on the amplitude and polarity of previously applied bias voltage. The higher responsivity of the RTA photodiodes makes them useful as light sensors. [ABSTRACT FROM AUTHOR]

This study examines the electrical properties and material characteristics of hafnium zirconium oxide thin films under various annealing and etching processes. High-pressure annealing is shown to significantly enhance the orthorhombic phase fraction, reaching 42% at 700 °C, with supercritical fluids treatment further increasing this to 46%. The impact of atomic layer etching and reactive ion etching on surface roughness is also analyzed, revealing increases of approximately 3.5 and 7 Å, respectively, which are mitigated by subsequent rapid thermal annealing. Additionally, high-pressure annealed capacitors exhibit a reduction in leakage current density from 10−7 to 10−9 A/cm2 and an increase in remnant polarization from 14 to 18 μC/cm2. Transmission electron microscopy and x-ray photoelectron spectroscopy confirm these processes' significant impact on the structure and performance, highlighting their value for future high-performance electronic devices. [ABSTRACT FROM AUTHOR]

Ultra-thin HfTiOx dielectric films (Ti ~ 26.6%) of thickness ~ 12 nm have been deposited through an RF magnetron co-sputtering process on strained Si0.81Ge0.19 substrates. Samples (HT1, HT2, and HT3) treated by rapid thermal annealing at temperatures ranging from 350 °C to 550 °C were compared with as-deposited samples. From the C–V characteristics of the Au/HfTiOx/p-Si0.81Ge0.19 metal–insulator–semiconductor capacitors, recorded at various frequencies ranging between 50 kHz and 1 MHz, it has been observed that the maximum accumulation capacitance, Cmax , was enhanced to 94 pF after a post-deposition anneal at 350 °C, indicating the formation of a superior interface. The smallest frequency-dependent flat band voltage shift of 0.26 V and the minimum interface trap density (Dit) of 8.62 × 1011 eV−1 cm−2 were both recorded for the HT1 sample. Inelastic tunneling spectroscopy (IETS), a highly sensitive and reliable technique for defect analysis, was then used to evaluate the quality of metal–insulator–semiconductor capacitors. It has been demonstrated that the IETS technique can be used to identify the signatures of different traps. Defect analysis using IETS also helps to understand the microscopic origins of traps and thus can be subsequently used for the estimation of their energy levels, as well as their spatial locations within the dielectric. A comprehensive analysis of the microscopic bonding structures and chemical compositions of hafnium-based high-k gate dielectrics and strained-SiGe interface layers is presented. [ABSTRACT FROM AUTHOR]

Our study aims to clarify the morphotropic phase boundary observed in Zr-doped hafnia systems. We utilize density-functional-theory calculations to examine various structural phases of (Hf,Zr)O 2 thin films on TiN electrodes. We account for Zr composition, film thickness, and temperature to model the free energy of (Hf,Zr)O 2 on TiN electrodes. Our assessment of the thermodynamic stability of each structural phase in terms of surface and interface energies under the substrate strain allows us to determine that the substrate strain and temperature significantly reduce the energy differences between different phases. Our findings lead to the energy reversal between tetragonal and orthorhombic phases when the film thickness increases. Based on our results, we propose that the formation of a high-temperature tetragonal phase, arising from the rapid thermal or annealing processes, is crucial to the appearance of the morphotropic phase boundary in Hf 0.5 Zr 0.5 O 2. Understanding the origin of the morphotropic phase boundary can have significant implications for device applications. [ABSTRACT FROM AUTHOR]

We report abrupt Te doping of GaInP solar cells grown by molecular beam epitaxy (MBE) through the use of a low substrate temperature of 420 °C and subsequent elimination of surface segregation. First, a Te surface pre-dose layer and reduced substrate temperature were required to achieve abrupt profiles at doping >1 × 1018 cm−3 in calibration samples, while reduced doping of 5.7 × 1017 cm−3 did not require the surface layer. Next, we demonstrate front-junction n+/p GaInP cells with an improved internal quantum efficiency (IQE) after Te doping of the n-type emitter directly attributable to an ∼2.5× higher carrier diffusion length, with IQE-derived short-circuit current density increasing from 13.2 to 14.1 mA/cm2. Rapid thermal annealing further boosted the performance through improvements in the minority carrier lifetime of the p-GaInP base. The use of low substrate temperature in MBE-grown GaInP enables abrupt Te doping profiles to be attained in a straightforward manner and is promising for both solar cells and tunnel junctions. [ABSTRACT FROM AUTHOR]

Materials with room‐temperature phosphorescence (RTP) from deep red to near‐infrared (NIR) region exhibit great potential for emerging applications. However, such molecules typically require a low‐lying first triplet (T1) excited state, which may not be optimal for exciton stabilization, potentially compromising the phosphorescence lifetime. This study reports the design of four 9H‐carbazole (Cz) analogs with extended conjugation lengths used as dopants to achieve RTP emissions in deep red and NIR regions with lifetimes exceeding 700 ms. These findings reveal that substituting reactive hydrogen atoms in Cz analogs with methyl groups significantly enhances the photoluminescence quantum yield (PLQY) of these materials compared to their non‐methylated counterparts. Additionally, these doping systems can be activated by visible light, achieving persistent phosphorescence even under the excitation of 450 nm light. Theoretical calculations demonstrate the crucial roles of charge transfer state and the enhanced spin‐orbital coupling (SOC) matrix elements upon doping for achieving long‐lifetime phosphorescence beyond 600 nm. This research presents a strategy employing Cz‐based doping systems to facilitate RTP emissions extending from visible to deep red and NIR regions. [ABSTRACT FROM AUTHOR]

Al 2 O 3 /ZnO nanolaminates are promising for thin-film transistors and photoluminescence applications. In this work, the thermal induced interface changes of Al 2 O 3 /ZnO nanolaminates were studied as a function of the in site deposition temperature and rapid post-annealing temperature. The Al 2 O 3 /ZnO nanolaminates were grown by atomic layer deposition system at 80 °C, 120 °C, and 250 °C, and further post-annealed in a rapid thermal processing (RTP) furnace at 600 °C, 700 °C, and 800 °C for 10 min, separately. Then the microstructures, interfacial diffusion and solid-phase reactions of the Al 2 O 3 /ZnO nanolayers were systematically investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HR-TEM). The results show that the in situ growth temperature directly affects the crystallinity and selective orientation of the ZnO interlayers, which further induce the ZnO interlayers to undergo completely different interfacial diffusion and solid-phase reactions during the rapid post-annealing processing. The films grown at 80 °C were close to amorphous, while those grown at 120 °C had a distinctly dominant orientation and exhibited better crystallization at 250 °C. The presence of the ZnAl 2 O 4 grains indicates the solid-phase reactions have occurred on the ZnO/Al 2 O 3 interface during the rapid post-annealing at 700 °C or above. [ABSTRACT FROM AUTHOR]

Synthesis of color‐tunable ultralong room temperature phosphorescence (RTP) crystals with multilevel stimuli‐responsive properties is highly desirable due to their tremendous application prospects but has rarely been explored. Herein, a 2D organic–inorganic metal‐halide hybrid (ABA2CdCl4) has been originally designed and synthesized with efficient blue fluorescence and green RTP through Cd induced heavy atom effect. Due to the improved intermolecular interactions and enhanced light absorption, a high RTP efficiency up to 34% is achieved in ABA2CdCl4. With ABA2CdCl4 as a prototype, Mn2+‐doping strategy is successfully employed to construct multicomponent RTP material with wide‐tunable RTP property in response to multilevel external stimulus such as time, temperature and light. More importantly, Mn2+ pairs are formed in Mn2+‐doped ABA2CdCl4, which are observed in 2D metal‐halide hybrids for the first time. Due to the thermal assisted energy transfer from triplet excitons (organic unit) to Mn2+ pairs, and the thermally activated emission from Mn2+ pairs, tunable RTP colors between 270 and 333 K are easily realized, showing the highest sensitivity against temperature reported so far. By virtue of the above advantages, such materials are successfully applied in multilevel information storage and temperature sensors. The work promotes the development of multi‐stimuli responsive RTP systems based on hybrid metal halides. [ABSTRACT FROM AUTHOR]

As interest in transparent electronics increases, ensuring the reliability of transparent RRAM (T-RRAM) devices, which can be used to construct transparent electronics, has become increasingly important. However, defects and traps within these T-RRAM devices can degrade their reliability. In this study, we investigated the improvement of transparency and reliability of T-RRAM devices with an AZO/HfO2/Ti structure through rapid thermal annealing (RTA) at 450 °C for 60 s in a nitrogen atmosphere. The device without RTA exhibited a low transmittance of 30%, whereas the device with RTA showed a significantly higher transmittance of over 75%. Furthermore, the device operated at lower current levels after RTA, which resulted in a reduction in its operating voltages, and the forming, setting, and reset voltages changed from 3.3, 2.4, and −5.1 V, respectively, to 2, 1, and −2.7 V. This led to an improvement in the endurance characteristics of the device, which thereby suggests that these improvements can be attributed to a reduction in the defects and trap density within the T-RRAM device caused by RTA. [ABSTRACT FROM AUTHOR]

α‐Sn, a new elemental topological quantum material, has drawn substantial attention lately. Unique transport properties and intriguing spintronics applications of α‐Sn are demonstrated, resurrecting this material from its notorious "tin pest" infamy. With a diamond cubic crystal structure, group‐IV α‐Sn holds the potential for integrated topological quantum devices on Si. However, directly growing α‐Sn on Si is still challenging due to the ≈20% lattice mismatch. Here, a new method is demonstrated to grow 200 nm‐thick α‐Sn microstructures on a 2 nm‐thick Ge seed layer on Si substrate by physical vapor deposition. In situ Raman spectroscopy reveals that the as‐deposited β‐Sn melts upon rapid thermal annealing at 350–450 °C and solidifies to α‐Sn after cooling back to room temperature, seeded by heterogeneous nucleation on the Ge layer. Cooling condition and HCl etching are tuned to achieve phase‐pure α‐Sn microstructures toward quantum devices. Approximately 1 at.% Ge is alloyed into α‐Sn due to diffusion from the Ge seed layer, which helps stabilize α‐Sn thermodynamically to facilitate device processing. A compressive strain is incorporated into these α‐Sn microstructures, making them 3D topological Dirac semimetals for integrated quantum devices on Si. [ABSTRACT FROM AUTHOR]

We evaluate the material characteristics of superconducting platinum silicide (PtSi) thin films as candidate materials for superconducting quantum information devices compatible with silicon technology. These films were synthesized using magnetron sputtering under ultrahigh vacuum conditions, followed by rapid thermal annealing. Polycrystalline PtSi films synthesized by this method have the favorable properties of superconducting critical temperature of 0.95 K and relatively long zero-temperature Ginzburg-Landau coherence length of 76 nm. We further studied coplanar microbridge devices fabricated by electron beam lithography and chlorine-free reactive ion etching, finding that the temperature-dependent critical current density follows the Ginzburg Landau depairing mechanism. [ABSTRACT FROM AUTHOR]

Surface‐enhanced Raman spectroscopy (SERS) has a wide range of applications in molecular recognition, environmental pollutant detection, and other fields. However, the intensity and number of "hot spots" in 1D and 2D nanostructures are limited due to the scale‐dependent localized plasmonic effect of nanostructures, making it difficult to increase the detection limit. Herein, a kind of 3D substrate called Au@Ag double‐layer nanoarray (Au@Ag DLA) is prepared using rapid thermal annealing and chemical replacement methods. The energy‐dispersive spectrometer spectra confirm the successful growth of AgNPs on the gold nanoarray (Au SLA) by showing no presence of the copper element, indicating complete replacement of the Cu film deposited on Au SLA by Ag atoms. The detection limit of malachite green in Au@Ag DLA is 10−8 mol L−1, four and three orders of magnitude higher than that of Au SLA and AgNPs, respectively. This stronger SERS effect of Au@Ag DLA arises from the larger number of intense hot spots generated not only on the horizontal surface but also in the vertical direction. This finding provides a method for developing efficient and stable 3D SERS substrate, which can be utilized for the trace detection of water pollutants and pesticide residue. [ABSTRACT FROM AUTHOR]

Exploring the morphogical and structural properties along with gas sensing applications both pure and Ti-doped SnO2 ultra-thin films, were meticulously crafted on micromachined silicon substrate heater devices using a combination of classical soft chemical processes and hydrothermal techniques (SCPHTP). The fabrication process involved a two-step approach: initially, a 20nm layer of tin oxide was hydrothermally deposited onto the substrates, followed by annealing in wet air at 600∘C for 5h using a standardized temperature variation protocol. Subsequently, secondary layers with thicknesses of 20, 40 and 60nm were sequentially deposited onto the tin dioxide devices and oxidized in wet air at 550∘C and 600∘C for 20h each, using the same temperature modulation scheme. Throughout this process, the hydrothermal deposition temperature remained constant at 180∘C for both the initial and secondary layers of tin dioxide deposition. Additionally, Ti layers with thicknesses of 4 and 8nm were deposited onto the 20nm + 40nm system, subjected to annealing at 550∘C for 20h, followed by 1-min annealing in dry O2 at 700∘C and 800∘C, respectively, using a Rapid Thermal Annealing (RTA) system. Characterization of the crystalline and surface structures of the devices revealed a transformation of the soft chemical tin dioxide solution into the cassiterite structure of SnO2, resulting in uniform large surface areas for the sensor devices. Moreover, Ti metal layers of 4 and 8nm thicknesses were fully converted into TiO2 on the surface of the devices. Subsequent testing showcased higher current values in sandwich systems of 20nm + 60nm and 20nm + 40nm compared to the 20nm + 20nm configuration. Sensitivity and stability assessments for various volatile organic compounds (VOCs) and CO gases at a constant DC temperature of 400∘C indicated excellent performance, with sensitivity to CO gas being contingent on relative humidity (RH). Notably, RTA-annealed and Ti-8 nm-doped sensor devices exhibited superior sensitivity and reproducibility, particularly when treated at 800∘C in dry O2 for 1min. This heightened performance can be attributed to the occupation of chloride ions in the oxygen sites of the as-synthesized SnO2, resulting in enhanced sensing capabilities for VOC gases. [ABSTRACT FROM AUTHOR]

Aqueous room‐temperature phosphorescence (RTP) materials have garnered considerable attention for their significant potential across various applications such as bioimaging, sensing, and encryption. However, establishing a universally applicable method for achieving aqueous RTP remains a substantial challenge. Herein, we present a versatile supramolecular strategy to transition RTP from solid states to aqueous phases. By leveraging a cyclic peptide‐based supramolecular scaffold, we have developed a noncovalent approach to molecularly disperse diverse organic phosphors within its rigid hydrophobic microdomain in water, yielding a series of aqueous RTP materials. Moreover, high‐performance supramolecular phosphorescence resonance energy transfer (PRET) systems have been constructed. Through the facile co‐assembly of a fluorescent acceptor with the existing RTP system, these PRET systems exhibit high energy transfer efficiencies (>80 %), red‐shifted afterglow emission (520–790 nm), ultralarge Stokes shifts (up to 450 nm), and improved photoluminescence quantum yields (6.1–30.7 %). This study not only provides a general strategy for constructing aqueous RTP materials from existing phosphors, but also facilitates the creation of PRET systems featuring color‐tunable afterglow emission. [ABSTRACT FROM AUTHOR]

Dynamic organic room‐temperature phosphorescence (RTP) materials are highly promising for various applications. However, developing photo‐responsive RTP systems with simple fabrication, high reversibility, and visible‐light responsiveness presents a significant challenge. Herein, in situ embedding of boron‐doped carbon dots (B‐CDs) in amorphous polymer (pPBA) is achieved by a two‐step polymerization and carbonization process. Impressively, the B‐CDs@pPBA composite exhibits visible‐light‐activated ultralong RTP with full reversibility and a lifetime on–off ratio exceeding 280. By correlating photophysical properties with structural characterization results, it is concluded that photoinduced intensifying of the crosslinking between B‐CDs and pPBA is responsible for the dynamic RTP. More interestingly, the B‐CDs@pPBA film is found to display bending actuation and reversible deformable behavior upon light exposure. Finally, potential applications of such photo‐responsive systems in programmable information storage and encryption are demonstrated. This research may pave a new way for the development of dynamic RTP nanomaterials and promote their use in a wide range of promising applications. [ABSTRACT FROM AUTHOR]

Vanadium dioxide (VO2), a current favorite in the field of smart windows as a thermochromic material, faces limitations in practical application due to its high phase transition temperature (Tt, ~ 68 ℃) and wide hysteresis curve (ΔT). In this study, Ru-doped VO2 thin films with reduced Tt and narrower ΔT were prepared through co-sputtering tetravalent metal Ru and V using magnetron sputtering to form alloy thin films, followed by rapid thermal annealing. Compared with pure VO2 thin films, at the Ru doping concentration of 4.98 at%, the Tt was lowered from 59.6 °C to 35.8 °C, and the ΔT was reduced from 10.5 °C to 2.8 °C, primarily due to the structural similarity between RuO2 and rutile phase VO2, smaller grain size, and greater grain uniformity. The optical properties of Ru-doped VO2 thin films had also been discussed, revealing only minor reductions in luminous transmittance (Tlum) and the solar modulation ability (ΔTsol) when the Tt decreased to 35.8 °C. This methodology offers a viable path for applying VO2 in smart windows, providing effective reductions in Tt and ΔT with minimal impact on optical performance. [ABSTRACT FROM AUTHOR]

Dopant‐selective electrochemical etching (ECE) of gallium nitride (GaN) results in well‐defined porous layers with tunable refractive index, which is extremely interesting for integrating photonic components into nitride technology. Herein, the impact of nitrogen implantation with and without subsequent rapid thermal annealing (RTA) on the porosification process of highly n‐doped GaN ([Si] 3 × 1019 cm−3) is investigated. Implantation is expected to compensate the donors of the n‐GaN layer to spatially suppress porosification during ECE. Optical transmission, electrochemical capacitance–voltage, and X‐Ray diffractometry of as‐grown and as‐implanted GaN suggest successful compensation of n‐dopants. Cross‐sectional scanning electron microscopy reveals the presence of mesopores (diameter 2–50 nm) after ECE of the as‐grown n‐GaN. In the case of implanted n‐GaN, it is found that ECE results in macropores (diameter > 50 nm), which can be suppressed by an intermediate RTA step. The implanted and annealed n‐GaN layers solely exhibit mesopores at the top and bottom, while the intermediate region remains unimpaired. Chronoamperometry and gravimetry provide additional insight and confirm the presence of macro‐ and mesopores in samples without and with RTA, respectively. The results demonstrate a successful implementation of etch‐resisting subsurface layers, which are required for 3D refractive index engineering in porous GaN. [ABSTRACT FROM AUTHOR]

In this paper, we investigate the resistive switching (RS) behavior of Cu/ZnO/ITO devices subjected to various rapid thermal annealing (RTA) temperatures under vacuum. Current–voltage characteristics reveal that following the application of a positive electroforming voltage, both unannealed ZnO films and those annealed at 200 °C exhibit bipolar RS, consistent with the electrochemical metallization mechanism (ECM). However, films annealed at higher temperatures exhibit RS with both positive and negative electroforming threshold voltages and coexistence of switching in both polarities. Ultimately, these films display RS behavior aligned with the valence change mechanism (VCM), dominated by a negative electroforming voltage and RS on the negative bias side, while positive electroforming voltage and RS vanish for films annealed at 600 °C. Curve fitting analysis was conducted for Schottky emission (SE), space-charge limited current, and Poole–Frenkel (PF) emission mechanisms, with SE and PF emission providing better fits. These results demonstrate the tunability of ECM and VCM RS modes and the polarity of the forming bias, underscoring the potential of vacuum RTA in advancing ZnO-based memory device development. [ABSTRACT FROM AUTHOR]

We report an ultra-shallow p-type doping of silicon resulting from the rapid thermal annealing of thin Al2O3 films deposited on intrinsic silicon with a native SiO2 layer, using a common atomic layer deposition process. Characterization revealed a two-stage decrease in sheet resistance, providing insights into the doping mechanism. [ABSTRACT FROM AUTHOR]

Acetone detection is of significant importance in various industries, from cosmetics to pharmaceuticals, bioengineering, and paints. Sensor manufacturing involves the use of different semiconductor materials as well as different metals for doping and functionalization, allowing them to achieve advanced or unique properties in different sensor applications. In the healthcare field, these sensors play a crucial role in the non-invasive diagnosis of various diseases, offering a potential way to monitor metabolic conditions by analyzing respiration. This article presents the synthesis method, using chemical solutions and rapid thermal annealing technology, to obtain Al-functionalized and Ni-doped copper oxide (Al/CuO:Ni) nanostructured thin films for biosensors. The nanocrystalline thin films are subjected to a thorough characterization, with examination of the morphological properties by scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX), and X-ray diffraction (XRD) analysis. The results reveal notable changes in the surface morphology and structure following different treatments, providing insight into the mechanism of function and selectivity of these nanostructures for gases and volatile compounds. The study highlights the high selectivity of developed Al/CuO:Ni nanostructures towards acetone vapors at different concentrations from 1 ppm to 1000 ppm. Gas sensitivity is evaluated over a range of operating temperatures, indicating optimum performance at 300 °C and 350 °C with the maximum sensor signal (S) response obtained being 45% and 50%, respectively, to 50 ppm gas concentration. This work shows the high potential of developed technology for obtaining Al/CuO:Ni nanostructured thin films as next-generation materials for improving the sensitivity and selectivity of acetone sensors for practical applications as breath detectors in biomedical diagnostics, in particular for diabetes monitoring. It also emphasizes the importance of these sensors in ensuring industrial safety by preventing adverse health and environmental effects of exposure to acetone. [ABSTRACT FROM AUTHOR]

This study investigates the possible impact of the dopant distribution on the electrical characteristics of silicon-on-insulator p-n diodes with varying nanostructure widths. The devices were fabricated using rapid thermal annealing and electron-beam lithography, with the p-n junction formed in a region codoped with boron (B) acceptors and phosphorus (P) donors. Electrical measurements conducted at low temperatures reveal significant differences in electronic transport behavior for different widths, especially within the negative differential conductance region. The findings suggest that the band-to-band tunneling is strongly influenced by the dopant (impurity) and/or defect levels in the depletion layer, with a narrower device showing a pronounced dependence on the substrate voltage. [ABSTRACT FROM AUTHOR]

Energy dispersive X-ray microanalysis is one of the main methods for determining the elemental composition of matter. Possessing high locality and a relatively shallow penetration depth of the electron beam (

We investigate terahertz time-domain spectroscopy (THz-TDS) as a non-destructive and non-contact technique for depth profiling of dopants in semiconductors. THz temporal waveforms transmitted through silicon-ion-implanted semi-insulating gallium arsenide substrates, as-implanted or post-annealed by rapid thermal annealing, were analyzed by assuming a multi-layered Gaussian refractive index profile in the ∼sub-micrometer-thick implantation region. The implantation energy and dosages in this work were 200 KeV, 1014, 5 × 1014, and 1015 ions/cm2, respectively. The average values of real (n) and imaginary (κ) parts of refractive indices of an as-implanted sample in the depth range of 0–800 nm are 5.8 and 0.7, respectively, at 0.5 THz and are 6.2 and 0.2, respectively, at 1 THz. On the other hand, the refractive index profile of the post-annealed samples displays a prominent Gaussian-like form, and peak refractive indices (n ∼ 25 and κ ∼ 32.7 at 0.5 THz and n, κ ∼17 at 1 THz) were found to be at the depth of 210 nm. Reconstructed dopant profiles in as-implanted, implanted, and post-annealed substrates were found to be in good agreement with measurements by secondary ion mass spectroscopy as well as simulation by the Monte Carlo method. We were also able to determine accurately the projected range (Rp), straggle (Rs), and concentration of dopants by the analysis of THz-TDS data. The spatial resolution, along the depth direction, of the THz-TDS technique for depth profiling of dopants was estimated to be as small as 8-nm. This work suggests the feasibility of using THz-TDS for nondestructive and non-contact diagnostics for profiling dopants in semiconductors. [ABSTRACT FROM AUTHOR]

BiVO4 is one of the most promising candidates for photoelectrochemical water oxidation. However, the poor crystallinity and short hole diffusion length limit its charge separation. One bottleneck stems from the contradiction between high crystallinity and small particles via conventional furnace heating processes. This paper describes the design and fabrication of BiVO4 photoanodes via rapid thermal process (RTP), rather than furnace heating, to decouple the constraints between nucleation, crystallization, and growth processes of BiVO4. The higher heating ramp rate of RTP compared with furnace heating promotes the fast diffusion of reactant molecules, which elevates the nucleation rate above the particle growth rate of BiVO4, leading to small particles with high crystallinity. Moreover, the ultra‐high heating temperature makes it possible to crystallize the small BiVO4 particle within a short time. Thus, a high crystallinity can be obtained for the RTP‐treated BiVO4 while maintaining small particle size, achieving a charge separation efficiency of up to 82%, 30% higher than that of furnace‐treated BiVO4 photoanode. [ABSTRACT FROM AUTHOR]

Over the years, numerous outstanding research groups around the world have been working tirelessly on metallic SERS substrates. Although these efforts have led to the development of various sensors and pushed the field forward, today this line of research seems saturated and exhausted. In this work, we address this issue by exploring an emerging topic in recent literature: the fabrication of high-performance TiN SERS-active structures. TiN thin film was sputtered onto pyramidal Si microstructures. Spectroscopic ellipsometry measurements confirmed the plasmonic properties of the TiN material above its plasma wavelength of 515 nm. The Si-TiN surface was subsequently modified with an Au layer, which was then transformed into Au nanoparticles (Au NPs) during the Rapid Thermal Annealing process. The Si-TiN-AuNPs samples exhibited the highest extinction intensity, as well as the best SERS signal intensity for the model Raman reporter molecule. Further analysis of the SERS data showed that the presence of the Au thin film only moderately increased SERS activity, while Au NPs enhanced the SERS signal by one order of magnitude. Final Si-TiN-AuNPs platforms were successfully employed for the detection of vitamin B12, demonstrating a low limit of detection (8.57•10–8 M) along with excellent point-to-point repeatability. [ABSTRACT FROM AUTHOR]

Our study investigates heterogeneous co-doped HfO2 thin films integrated into metal-ferroelectric-metal stacks, achieved by incorporating multiple layers doped with various species during the atomic layer deposition process. This approach creates an artificial crystallization temperature gradient across the HfO2 film, influencing the preferred nucleation sites of HfO2 during rapid thermal processing. Our findings demonstrate that the phase composition of the annealed HfO2 film is primarily determined by heterogeneous or homogeneous crystallization processes. In cases of heterogeneous crystallization, where crystallization initiates from nuclei formed at electrode/HfO2 interfaces, grains predominantly crystallize in the orthorhombic phase. Conversely, grains are more likely to crystallize in the monoclinic phase if they originate from nuclei formed at the center of the HfO2 film. Additionally, we observe correlations between the texture of the HfO2 film and the texture of the electrodes. [ABSTRACT FROM AUTHOR]

The vast high entropy alloy (HEA) composition space is promising for discovery of new material phases with unique properties. This study explores the potential to achieve rare‐earth‐free high magnetic anisotropy materials in single‐phase HEA thin films. Thin films of FeCoNiMnCu sputtered on thermally oxidized Si/SiO2 substrates at room temperature are magnetically soft, with a coercivity on the order of 10 Oe. After post‐deposition rapid thermal annealing (RTA), the films exhibit a single face‐centered‐cubic phase, with an almost 40‐fold increase in coercivity. Inclusion of 50 at.% Pt in the film leads to ordering of a single L10 high entropy intermetallic phase after RTA, along with high magnetic anisotropy and 3 orders of magnitude coercivity increase. These results demonstrate a promising HEA approach to achieve high magnetic anisotropy materials using RTA. [ABSTRACT FROM AUTHOR]

Ferrimagnetic iron garnets enable magnetic and magneto‐optical functionality in silicon photonics and electronics. However, garnets require high‐temperature processing for crystallization which can degrade other devices on the wafer. Here bismuth‐substituted yttrium and terbium iron garnet (Bi‐YIG and Bi‐TbIG) films are demonstrated with good magneto‐optical performance and perpendicular magnetic anisotropy (PMA) crystallized by a microheater built on a Si chip or by rapid thermal annealing. The Bi‐TbIG film crystallizes on Si at 873 K without a seed layer and exhibits good magneto‐optical properties with Faraday rotation (FR) of −1700 deg cm−1. The Bi‐YIG film also crystallizes on Si and fused SiO2 at 873 K without a seed layer. Rapidly cooled films exhibit PMA due to the tensile stress caused by the thermal expansion mismatch with the substrates, increasing the magnetoelastic anisotropy by 4 kJ m−3 versus slow‐cooled films. Annealing in the air for 15 s using the microheater yields fully crystallized Bi‐TbIG on the Si chip. [ABSTRACT FROM AUTHOR]

The facile spin coating fabrication of high‐dielectric‐constant (high‐k) multicomponent (Al,Ti,V,Zr,Hf)Ox films with an equivalent oxide thickness of ≈0.95 nm and the investigation of their thermal stability and dielectric and electrical properties of the resulting advanced metal–oxide–semiconductor (MOS)‐based electronic devices are reported in this study. Various heating conditions, including drying following spin coating, annealing after drying, and forming gas annealing, were investigated to optimize the quality of the films and reduce film defects. The favorable film‐based MOS devices exhibited robust capacitance–voltage (C–V) and current–voltage (I–V) characteristics with a remarkable k value of approximately 62 at 1 kHz. The thermal stability of the films was affirmed through a rapid thermal annealing treatment at 900°C for 5 s and observation of nondegraded C–V and I–V curves. The electrical performance of the resulting MOS field‐effect transistors (MOSFETs), including a threshold voltage of 0.4 V, an on/off ratio of 106, a saturated mobility of 40.1 cm2 V−1 s−1, and a subthreshold swing of 66.7 mV dec−1, was obtained. Moreover, hole‐ and electron‐trapping measurements through negative and positive gate bias stress instabilities, respectively, indicate the reliable performance of our MOSFETs. Our results imply that solution‐based processes are promising for fabricating fundamental semiconductor devices. [ABSTRACT FROM AUTHOR]

The development of tight ceramic ultrafiltration membranes for water purification facilitates is challenging because of high fabrication costs and low permeate flux. In this study, a low-energy rapid thermal process (RTP) was comprehensively investigated for fabricating of high-precision, permeable α-alumina tight ultrafiltration membranes. Compared to the conventional thermal process (CTP), RTP offers an ultra-fast heating rate and shorter holding time, effectively mitigating grain growth and pore aggregation. Moreover, the decomposition of organic matter is delayed during RTP, providing a lower interfacial energy that enables direct formation of α-alumina at a low temperature of 750 °C. During a secondary subsequent RTP, the residual phase is fully converted to α-alumina by the in-situ seeding effect. By utilizing RTP, we successfully prepared α-alumina ultrafiltration membranes within 30 min by calcination, with an average pore size of approximately 6 nm, a narrow pore distribution coefficient of 1.12, and high permeance of 219 L−1·m−2·h−1·bar−1. [ABSTRACT FROM AUTHOR]

In the present work, thin films of bimetallic palladium–silver (Pd50Ag50 and Pd70Ag30) alloy on silicon substrates are deposited by direct current magnetron cosputtering in a vacuum chamber at a pressure of 10−7 Torr. The formation of the alloy is confirmed by the shift of x-ray diffraction peaks as compared to the pure phases of the metals. The films are subjected to rapid thermal annealing at 500 °C for 120 s. Surface-enhanced Raman spectroscopy (SERS) is performed for low level detection of two analytes: crystal violet (dye) and tetryl (an explosive). The SERS signals are observed only in the case of the rapid thermal annealed films. The lowest concentration of the dye detected with Pd50Ag50 is 100 μM. In comparison, it is 250 μM for Pd70Ag30, indicating that a higher content of silver in the alloy is desirable from a SERS perspective due to its more robust plasmonic activity. [ABSTRACT FROM AUTHOR]

We report herein the analysis of the properties of copper(I) oxide thin films deposited by an optimized ammonium-free successive ion layer adsorption and reaction (SILAR) technique. The Cu2O thin film deposition process was carried out at room temperature using copper acetate monohydrate, sodium citrate as complexing agent, and hydrogen peroxide as precursors of copper and oxygen ions, respectively. The harmless and easy-to-handle sodium citrate replaces the volatile NH4OH commonly employed as complexing agent in the SILAR technique for the deposition of metal oxide thin films. The optical, structural, morphological, and electrical properties of the as-deposited Cu2O thin films were studied as a function of the number of cycles during deposition, as well as their modifications produced by the effect of rapid thermal annealing (RTA) in vacuum in a temperature range of 200–250°C for 1 min, 3 min, and 5 min. The as-deposited thin films had cubic crystalline structure corresponding to the Cu2O phase as determined by x-ray diffraction (XRD), with a direct energy bandgap of 2.43–2.51 eV depending on the number of cycles, and electrical resistivity of the order of 103 Ω cm. The XRD and x-ray photoelectron spectroscopy (XPS) analysis of the Cu2O thin films treated by RTA demonstrated an increase of the crystal size with time and temperature of the RTA and reduction effects from Cu2+ to Cu1+ oxidation states. On the other hand, the RTA treatments also decreased their energy bandgap to 2.38 eV and electrical resistivity to 102 Ω cm. The high energy bandgap values of the Cu2O thin films were attributed to quantum confinement effects produced by their small crystal size in the range of 3.6–8.6 nm. [ABSTRACT FROM AUTHOR]

To gain insight into the ferroelectric mechanisms under reduced thermal budget and thickness scaling, a 4.6 nm ultra-thin ferroelectric Hf0.5Zr0.5O2 capacitor compatible with back-end-of-line (BEOL) processes (all conducted at temperatures ≤ 350 °C) is investigated in this work. Through O3 pretreatment at the bottom electrode (BE) interface and controlled temperature modulation of the crystalline phase, the capacitor exhibits exceptional ferroelectric (FE) properties following low-temperature (350 °C) and long-term (300 s) rapid thermal annealing (RTA). These properties include high remanent polarization (2Pr ∼ 28.53 μC/cm2), low coercive voltage (Vc ∼ 0.43 V), effective leakage suppression, robust endurance (∼1010 cycles without hard breakdown), and a desirable high dielectric constant. The main mechanisms identified include tetragonal phase nucleation under enhanced tensile stress via the oxidized BE layer (TiO2), crystalline growth controlled through RTA temperature modulation, and phase transition to the ferroelectric orthorhombic phase under electric field cycling. This research provides valuable insights for the development of BEOL-compatible nonvolatile FE memories. [ABSTRACT FROM AUTHOR]

Polymeric room‐temperature phosphorescence (RTP) materials especially multicolor RTP systems hold great promise in concrete applications. A key feature in these applications is a triplet charge transfer transition. Aromatic electron donors and electron acceptors are often essential to ensure persistent RTP. There is much interest in fabricating non‐aromatic charge‐transfer‐mediated RTP materials and it still remains a formidable challenge to achieve color‐tunable RTP via charge transfer. Herein, a charge‐transfer‐mediated RTP material by embedding quinoline derivatives within a non‐aromatic polymer matrix such as polyacrylamide (PAM) or polyvinyl alcohol (PVA) is developed. Through‐space charge transfer (TSCT) is achieved upon alkali‐ or heat treatment to realize a long phosphorescence lifetime of up to 629.90 ms, high phosphorescence quantum yield of up to 20.51%, and a green‐to‐blue afterglow for more than 20 s at room temperature. This color‐tunable RTP emerges from a nonaromatic polymer to single phosphor charge transfer that has rarely been reported before. This finding suggests that an effective and simple approach can deliver new color‐tunable RTP materials for applications including multicolor display, information encryption, and gas detection. [ABSTRACT FROM AUTHOR]