This paper presents the experimental progress of laser-focused Cr atomic deposition and the experimental condition. The result is an accurate array of lines with a periodicity of 212.8±0.2 nm and mean full-width ...This paper presents the experimental progress of laser-focused Cr atomic deposition and the experimental condition. The result is an accurate array of lines with a periodicity of 212.8±0.2 nm and mean full-width at half maximum as approximately 95 nm. Surface growth in laser-focused Cr atomic deposition is modeled and studied by kinetic Monte Carlo simulation including two events： the one is that atom trajectories in laser standing wave are simulated with the semiclassical equations of motion to obtain the deposition position; the other is that adatom diffuses by considering two major diffusion processes, namely, terrace diffusion and step-edge descending. Comparing with experimental results （Anderson W R, Bradley C C, McClelland J J and Celotta R J 1999 Phys. Rev. A 59 2476）, it finds that the simulated trend of dependence on feature width is in agreement with the power of standing wave, the other two simulated trends are the same in the initial stage. These results demonstrate that some surface diffusion processes play important role in feature width broadening. Numerical result also shows that high incoming beam flux of atoms deposited redounds to decrease the distance between adatoms which can diffuse to minimize the feature width and enhance the contrast.展开更多
Atomic layer deposition(ALD)is extensively used to fabricate doped dielectrics due to its ability to deposit conformal films with atomic-scale thickness control.Al-doped TiO_(2)(ATO)is a promising high-k dielectric fo...Atomic layer deposition(ALD)is extensively used to fabricate doped dielectrics due to its ability to deposit conformal films with atomic-scale thickness control.Al-doped TiO_(2)(ATO)is a promising high-k dielectric for dynamic random access memory(DRAM)applications,offering a high dielectric constant with a remarkable leakage-lowering effect by Al acceptor doping.However,ATO fabrication via conventional supercycle-based ALD suffers from severe crystallinity loss during the growth of TiO_(2) upon Al doping owing to the dopant-induced lattice disorder.In addition,Al doping cannot reduce any inherent O vacancies(V_(O))of TiO_(2),although the original purpose of doping was to address the n-type nature caused by V_(O).To resolve these limitations,we propose a single-step,in-situ Ar/O_(2) post-doping plasma(PDP)process immediately after the Al dopant incorporation.Using the PDP process,simultaneous atomic-scale dopant migration-mediated crystallization and V_(O) annihilation were successfully initiated.Thus,the surface concentration of the dopant decreased,reducing the dopant-induced lattice distortion,while promoting the highly crystallized seed layer-like surface.Consequently,strong rutile-phase recovery was accompanied by enhanced lattice-matched growth.In addition,the PDP process significantly lowers the V_(O)-to-lattice oxygen ratio by facilitating the recombination between reactive O species and V_(O),increasing the corresponding 0.4 e V of conduction band offset(CBO).Despite the common trade-off between the dielectric constant and leakage,the Pt/PDP-ATO/Ru capacitor exhibited a simultaneous 30%increase in dielectric constant and up to a 1.6-order reduction in leakage current density.展开更多
Oxide semiconductors(OSs),introduced by the Hosono group in the early 2000s,have evolved from display backplane materials to promising candidates for advanced memory and logic devices.The exceptionally low leakage cur...Oxide semiconductors(OSs),introduced by the Hosono group in the early 2000s,have evolved from display backplane materials to promising candidates for advanced memory and logic devices.The exceptionally low leakage current of OSs and compatibility with three-dimensional(3D)architectures have recently sparked renewed interest in their use in semiconductor applications.This review begins by exploring the unique material properties of OSs,which fundamentally originate from their distinct electronic band structure.Subsequently,we focus on atomic layer deposition(ALD),a core technique for growing excellent OS films,covering both basic and advanced processes compatible with 3D scaling.The basic surface reaction mechanisms—adsorption and reaction—and their roles in film growth are introduced.Furthermore,material design strategies,such as cation selection,crystallinity control,anion doping,and heterostructure engineering,are discussed.We also highlight challenges in memory applications,including contact resistance,hydrogen instability,and lack of p-type materials,and discuss the feasibility of ALD-grown OSs as potential solutions.Lastly,we provide an outlook on the role of ALD-grown OSs in memory technologies.This review bridges material fundamentals and device-level requirements,offering a comprehensive perspective on the potential of ALD-driven OSs for next-generation semiconductor memory devices.展开更多
Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous Si...Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability.展开更多
The bismuth-telluride-based alloy is the only thermoelectric material commercialized for the applications of refrigeration and energy harvesting,but its low cost-effectiveness severely restricts its large-scale ap-pli...The bismuth-telluride-based alloy is the only thermoelectric material commercialized for the applications of refrigeration and energy harvesting,but its low cost-effectiveness severely restricts its large-scale ap-plication.The introduction of a porous structure in bulk thermoelectric materials has been theoretically proven to effectively reduce thermal conductivity and cost.However,the electrical properties of highly porous materials are considerably suppressed due to the strong carrier scattering at the interface be-tween the matrix and pores,ultimately leading to decreased figure of merit,ZT.Here,we use an atomic layer deposition strategy to introduce some hollow glass bubbles with nano-oxide layers into commercial Bi_(0.5)Sb_(1.5)Te_(3)for preparing high-performance porous thermoelectric materials.Experimental results indi-cate that the nano-oxide layers weaken carrier scattering at the interface between pores and matrix while maintaining high-strength phonon scattering,thereby optimizing carrier/phonon transport behaviors,and effectively increasing the ZT by 23.2%(from 0.99 to 1.22 at 350 K).Besides,our strategy has excellent universality confirmed by its effectiveness in improving the ZT of Bi_(2)Te_(2.7)Se_(0.3),therefore demonstrating great potential for developing low-cost and high-performance thermoelectric materials.展开更多
With the increase in the demand for wearable devices, temperature-sensing capability is an essential function for flexible and transparent applications. Particularly, the long-term stability of a device is highly desi...With the increase in the demand for wearable devices, temperature-sensing capability is an essential function for flexible and transparent applications. Particularly, the long-term stability of a device is highly desirable for use in daily life. In this study, a flexible and transparent self-powered temperature sensor with remarkable air stability was developed by employing a one-atom-thick monolayer graphene encapsulated with an extremely thin metal oxide layer. Graphene thermocouples were constructed by inducing p- and n-type doping on a high-quality monolayer graphene placed on a transparent polymer film. The entire graphene film was treated by a modulated oxygen plasma, which induced p-type doping with minimal defects on graphene. Half of the graphene was coated with polyethylenimine to form n-type graphene. The graphene p–n junction was encapsulated with a 14-nm-thick ultrathin Al_(2)O_(3) using atomic layer deposition (ALD). The graphene thermocouple exhibited a high Seebeck coefficient of 81.6 ± 2.4 µV/K, high linearity with a coefficient of determination of 0.999, rapid response with a time constant of 0.59 s, low thermal hysteresis, and wide operating temperature range. Owing to the ALD-Al_(2)O_(3) layer, the graphene thermocouple exhibited exceptional air stability, maintaining the Seebeck coefficient for 1028 days. Furthermore, the ultimate thinness of the graphene thermocouple rendered it with an extreme optical transmittance of 94.8 % at a wavelength of 550 nm and a small critical bending radius of 5.71 mm.展开更多
LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)is an attractive material for high-energy-density Li-ion batteries in electric vehicles.However,it suffers from rapid capacity fading.Previous studies have shown that tuning the ...LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)is an attractive material for high-energy-density Li-ion batteries in electric vehicles.However,it suffers from rapid capacity fading.Previous studies have shown that tuning the positive electrode material via atomic layer deposition(ALD)can enhance the electrochemical performance of the material.In this article,we introduce a novel coating method using gaseous precursors in an ALD reactor,where an AlO_(x)layer is deposited directly on the surface of the NMC811 precursor,followed by lithiation.The AlO_(x)coating is applied to the NMC811 powder substrate by exposing it to gas-phase precursors,using a conventional ALD and simplified ALD(chemical vapor deposition-like)method.It is observed that the novel methods lead to the incorporation of Al as a dopant within the bulk of NMC811,rather than forming a conformal AlO_(x)coating,after the final lithiation step.The optimized procedures result in positive electrode materials with higher capacity and enhanced cycling stability in both half-cell and full-cell configurations.Doping or coating was shown to mitigate transition metal dissolution,reduce side reactions between the active material and electrolyte,and improve structural stability.展开更多
Normally,a transparent inert film is coated on the surface of TiO_(2) particles to enhance the weatherability of the pigment.Liquid-phase coating process is mainly used in industry,which difficult to get really unifor...Normally,a transparent inert film is coated on the surface of TiO_(2) particles to enhance the weatherability of the pigment.Liquid-phase coating process is mainly used in industry,which difficult to get really uniform films.This work combining nanoparticle fluidization technology with atomic layer deposition(ALD) technology to achieve precise surface modification of a large number of micro-nano particles.First,we explored the fluidization characteristics of TiO_(2) nanoparticles in a home-made atmospheric fluidized bed ALD reactor(FB-ALD) to ensure the uniform fluidization of a large number of nanoparticles.Then TiCl_(4) and H_(2)O were used as precursors to deposit amorphous TiO_(2) films on the surface of TiO_(2) nanoparticles at 80℃ under atmospheric pressure,and the growth per cycle was about 0.109 nm per cycle.After 30 ALD cycles,the film thickness was about 3.1 nm,which could almost fully suppress the photocatalytic activity of TiO_(2).Compared with other traditional coating materials,amorphous TiO_(2) has higher light refractive index,and realizes the suppression of the photocatalytic activity of TiO_(2) without introducing other substances,demonstrating greater application potential in TiO_(2) pigment coating field.The process is a gas-phase coating method,which is efficient,no waste water,and easy to scale up.This work shown the excellent property of interface engineering in improving pigment weatherability and can also provide guidance for the nanoparticle surface modification.展开更多
Atomic layer deposition(ALD)has driven significant advancements in photovoltaic technologies by enabling the development of interlayers that improve both the efficiency and stability of devices.This review traces the ...Atomic layer deposition(ALD)has driven significant advancements in photovoltaic technologies by enabling the development of interlayers that improve both the efficiency and stability of devices.This review traces the evolution of ALD interlayers across various photovoltaic technologies,starting with early silicon solar cells and progressing into a variety of thin-film solar cells.We then delve into the role of ALD in state-of-the-art single-junction perovskite solar cells,particularly in optimizing the critical interfaces of perovskites/charge-transporting layers/-electrodes.Apart from that,we screen the functionality of ALD processing,which consists of reducing surface/interfacial defects and thus mitigating energy loss.Particularly,it enables efficient stacking of multiple thin layers,making a variety of tandem solar cells possible(silicon/perovskite,etc.)for higher efficiency.Moreover,the ALDprocessed interlayer prevents the ion migration between metals and perovskites,inhibiting the inter-diffusioninduced degradation of devices.Despite ALD technology extensively elevating the performance of above conventional/emerging solar cells,key challenges such as precursor flammability,cross-contamination during processing,and low deposition pace persist.We go over these challenges and expect our comprehensive overview of ALD techniques could shed light on pushing the envelope of photovoltaic efficiency.展开更多
Electrocatalysis is a promising approach to clean energy conversion due to its high efficiency and low environmental pollution. Noble metal materials have been studied to show high activity toward electrocatalyltic re...Electrocatalysis is a promising approach to clean energy conversion due to its high efficiency and low environmental pollution. Noble metal materials have been studied to show high activity toward electrocatalyltic reactions, although such applications remain restricted by the high cost and poor durability of the noble metals. By precisely adjusting the catalyst composition, size, and structure, electrocatalysts with excellent performance can be obtained. Atomic layer deposition(ALD) is a technique used to produce ultrathin films and ultrafine nanoparticles at the atomic level. It possesses unique advantages for the controllable design and synthesis of electrocatalysts. Furthermore, the homogenous composition and structure of the electrocatalysts prepared by ALD favor the exploration of structure-reactivity relationships and catalytic mechanisms. In this review, the mechanism, characteristics, and advantages of ALD in fabricating nanostructures are introduced first. Subsequently, the problems associated with existing electrocatalysts and a series of recently developed ALD strategies to enhance the activity and durability of electrocatalysts are presented. For example, the deposition of ultrafine Pt nanoparticles to increase the utilization and activity of Pt, fabrication of core–shell, overcoat, nanotrap, and other novel structures to protect the noble-metal nanoparticles and enhance the catalyst stability. In addition, ALD developments in synthesizing non-noble metallic electrocatalysts are summarized and discussed. Finally, based on the current studies, an outlook for the ALD application in the design and synthesis of electrocatalysts is presented.展开更多
Developing highly efficient magnetic microwave absorb-ers(MAs)is crucial,and yet challenging for anti-corrosion properties in extremely humid and salt-induced foggy environments.Herein,a dual-oxide shell of ZnO/Al_(2)...Developing highly efficient magnetic microwave absorb-ers(MAs)is crucial,and yet challenging for anti-corrosion properties in extremely humid and salt-induced foggy environments.Herein,a dual-oxide shell of ZnO/Al_(2)O_(3) as a robust barrier to FeSiAl core is introduced to mitigate corrosion resistance.The FeSiAl@ZnO@Al_(2)O_(3) layer by layer hybrid structure is realized with atomic-scale precision through the atomic layer deposition technique.Owing to the unique hybrid structure,the FeSiAl@ZnO@Al_(2)O_(3) exhibits record-high micro-wave absorbing performance in low-frequency bands covering L and S bands with a minimum reflection loss(RLmin)of-50.6 dB at 3.4 GHz.Compared with pure FeSiAl(RLmin of-13.5 dB,a bandwidth of 0.5 GHz),the RLmin value and effective bandwidth of this designed novel absorber increased up to~3.7 and~3 times,respectively.Fur-thermore,the inert ceramic dual-shells have improved 9.0 times the anti-corrosion property of FeSiAl core by multistage barriers towards corrosive medium and obstruction of the electric circuit.This is attributed to the large charge transfer resistance,increased impedance modulus|Z|0.01 Hz,and frequency time constant of FeSiAl@ZnO@Al_(2)O_(3).The research demonstrates a promising platform toward the design of next-generation MAs with improved anti-corrosion properties.展开更多
Noble single‐atom catalysts have rapidly been attracting attention due to their unique catalytic properties and maximized utilization.Atomic layer deposition(ALD)is an emerging powerful technique for large‐scale syn...Noble single‐atom catalysts have rapidly been attracting attention due to their unique catalytic properties and maximized utilization.Atomic layer deposition(ALD)is an emerging powerful technique for large‐scale synthesis of stable single atom.In this review,we summarize recent developments of single atom synthesized by ALD as well as explore future research direction and trends.展开更多
Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discuss...Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discussing this technique in catalysis.However,the mechanism on how the deposited materials improve the catalyst stability and tune the reaction selectivity is still unclear.Herein,catalytic systems created via ALD on stepwise preparation and/or modification under self-limiting reaction conditions are summarized.The effects of deposited materials in terms of electronic/geometry modification over the catalytic nanoparticles(NPs)are discussed.These effects explain the mechanism of the catalytic stability improvement and the selectivity modification.The unique properties of ALD for designing new catalytic systems are further investigated for building up photocatalytic reaction nanobowls,tandem catalyst and bi-active-component metallic catalytic systems.展开更多
Atomic layer deposition(ALD)has become an indispensable thin-film technology in the contemporary microelectronics industry.The unique self-limited layer-by-layer growth feature of ALD has outstood this technology to d...Atomic layer deposition(ALD)has become an indispensable thin-film technology in the contemporary microelectronics industry.The unique self-limited layer-by-layer growth feature of ALD has outstood this technology to deposit highly uniform conformal pinhole-free thin films with angstrom-level thickness control,particularly on 3D topologies.Over the years,the ALD technology has enabled not only the successful downscaling of the microelectronic devices but also numerous novel 3D device structures.As ALD is essentially a variant of chemical vapor deposition,a comprehensive understanding of the involved chemistry is of crucial importance to further develop and utilize this technology.To this end,we,in this review,focus on the surface chemistry and precursor chemistry aspects of ALD.We first review the surface chemistry of the gas–solid ALD reactions and elaborately discuss the associated mechanisms for the film growth;then,we review the ALD precursor chemistry by comparatively discussing the precursors that have been commonly used in the ALD processes;and finally,we selectively present a few newly-emerged applications of ALD in microelectronics,followed by our perspective on the future of the ALD technology.展开更多
Photoanodes based on In_2S_3/ZnO heterojunction nanosheet arrays(NSAs) have been fabricated by atomic layer deposition of ZnO over In_2S_3 NSAs, which were in situ grown on fluorine-doped tin oxide glasses via a facil...Photoanodes based on In_2S_3/ZnO heterojunction nanosheet arrays(NSAs) have been fabricated by atomic layer deposition of ZnO over In_2S_3 NSAs, which were in situ grown on fluorine-doped tin oxide glasses via a facile solvothermal process. The as-prepared photoanodes show dramatically enhanced performance for photoelectrochemical(PEC) water splitting, compared to single semiconductor counterparts. The optical and PEC properties of In_2S_3/ZnO NSAs have been optimized by modulating the thickness of the Zn O overlayer. After pairing with ZnO, the NSAs exhibit a broadened absorption range and an increased light absorptance over a wide wavelength region of 250–850 nm. The optimized sample of In_2S_3/ZnO-50 NSAs shows a photocurrent density of 1.642 m A cm^(-2)(1.5 V vs. RHE) and an incident photonto-current efficiency of 27.64% at 380 nm(1.23 V vs.RHE), which are 70 and 116 times higher than those of the pristine In_2S_3 NSAs, respectively. A detailed energy band edge analysis reveals the type-II band alignment of the In_2S_3/ZnO heterojunction, which enables efficient separation and collection of photogenerated carriers,especially with the assistance of positive bias potential, and then results in the significantly increased PEC activity.展开更多
Chromium(Cr)is a common heavy metal that has severe impacts on the ecosystem and human health.Capacitive deionization(CDI)is an environment-friendly and energy-efficient electrochemical purification technology to remo...Chromium(Cr)is a common heavy metal that has severe impacts on the ecosystem and human health.Capacitive deionization(CDI)is an environment-friendly and energy-efficient electrochemical purification technology to remove Cr from polluted water.The performance of CDI systems relies primarily on the properties of electrodes.Carbon-nanotubes(CNTs)membranes are promising candidates in creating advanced CDI electrodes and processes.However,the low electrosorption capacity and high hydrophobicity of CNTs greatly impede their applications in water systems.In this study,we employ atomic layer deposition(ALD)to deposit TiO_(2) nanoparticulates on CNTs membranes for preparing electrodes with hydrophilicity.The TiO_(2)-deposited CNTs membranes display preferable electrosorption performance and reusability in CDI processes after only 20 ALD cycles deposition.The total Cr and Cr(VI)removal efficiencies are significantly improved to 92.1%and 93.3%,respectively.This work demonstrates that ALD is a highly controllable and simple method to produce advanced CDI electrodes,and broadens the application of metal oxide/carbon composites in the electrochemical processes.展开更多
Since the first report of amorphous In–Ga–Zn–O based thin film transistors,interest in oxide semiconductors has grown.They offer high mobility,low off-current,low process temperature,and wide flexibility for compos...Since the first report of amorphous In–Ga–Zn–O based thin film transistors,interest in oxide semiconductors has grown.They offer high mobility,low off-current,low process temperature,and wide flexibility for compositions and processes.Unfortunately,depositing oxide semiconductors using conventional processes like physical vapor deposition leads to problematic issues,especially for high-resolution displays and highly integrated memory devices.Conventional approaches have limited process flexibility and poor conformality on structured surfaces.Atomic layer deposition(ALD)is an advanced technique which can provide conformal,thickness-controlled,and high-quality thin film deposition.Accordingly,studies on ALD based oxide semiconductors have dramatically increased recently.Even so,the relationships between the film properties of ALD-oxide semiconductors and the main variables associated with deposition are still poorly understood,as are many issues related to applications.In this review,to introduce ALD-oxide semiconductors,we provide:(a)a brief summary of the history and importance of ALD-based oxide semiconductors in industry,(b)a discussion of the benefits of ALD for oxide semiconductor deposition(in-situ composition control in vertical distribution/vertical structure engineering/chemical reaction and film properties/insulator and interface engineering),and(c)an explanation of the challenging issues of scaling oxide semiconductors and ALD for industrial applications.This review provides valuable perspectives for researchers who have interest in semiconductor materials and electronic device applications,and the reasons ALD is important to applications of oxide semiconductors.展开更多
Atomic layer deposition(ALD) is a versatile technique to deposit metals and metal oxide sensing materials at the atomic scale to achieve improved sensor functions. This article reviews metals and metal oxide semicondu...Atomic layer deposition(ALD) is a versatile technique to deposit metals and metal oxide sensing materials at the atomic scale to achieve improved sensor functions. This article reviews metals and metal oxide semiconductor(MOS) heterostructures for gas sensing applications in which at least one of the preparation steps is carried out by ALD. In particular, three types of MOS-based heterostructures synthesized by ALD are discussed, including ALD of metal catalysts on MOS, ALD of metal oxides on MOS and MOS core–shell(C–S) heterostructures.The gas sensing performances of these heterostructures are carefully analyzed and discussed.Finally, the further developments required and the challenges faced by ALD for the synthesis of MOS gas sensing materials are discussed.展开更多
Quantum dots(QDs)are promising candidates for the next-generation optical and electronic devices due to the outstanding photoluminance efficiency,tunable bandgap and facile solution synthesis.Nevertheless,the limited ...Quantum dots(QDs)are promising candidates for the next-generation optical and electronic devices due to the outstanding photoluminance efficiency,tunable bandgap and facile solution synthesis.Nevertheless,the limited optoelectronic performance and poor lifetime of QDs devices hinder their further applications.As a gas-phase surface treatment method,atomic layer deposition(ALD)has shown the potential in QDs surface modification and device construction owing to the atomic-level control and excellent uniformity/conformality.In this perspective,the attempts to utilize ALD techniques in QDs modification to improve the photoluminance efficiency,stability,carrier mobility,as well as interfacial carrier utilization are introduced.ALD proves to be successful in the photoluminance quantum yield(PLQY)enhancement due to the elimination of QDs surface dangling bonds and defects.The QDs stability and devices lifetime are improved greatly through the introduction of ALD barrier layers.Furthermore,the carrier transport is ameliorated efficiently by infilling interstitial spaces during ALD process.Attributed to the ultra-thin and dense coating on the interface,the improvement on optoelectronic performance is achieved.Finally,the challenges of ALD applications in QDs at present and several prospects including ALD process optimization,in-situ characterization and computational simulations are proposed.展开更多
The chalcogenides of platinum-group metals(PGMs)have been known to be present in minerals and the intermediate products of refining.Over recent years,their applications in various fields,including catalysis,have been ...The chalcogenides of platinum-group metals(PGMs)have been known to be present in minerals and the intermediate products of refining.Over recent years,their applications in various fields,including catalysis,have been explored.Given that certain PGM chalcogenides behave as compound semiconductors,they can be used as materials for photodetectors.In this study,RuS_(2),featuring a bandgap suitable for near-infrared photodetectors,was prepared by forming Ru on a SiO_(2)/Si substrate via the atomic layer deposition method using[Ru(TMM)(CO)_(3)]as the precursor.Annealing was conducted at 800℃ for 1 h under H_(2)S flow.High-resolution transmission electron microscopy(HRTEM)and X-ray diffraction(XRD)analysis clearly confirmed that the as-deposited hexagonal close-packed(hcp)Ru transformed to cubic RuS_(2) after post-annealing.The surface morphologies,chemical states,and electrical and optical properties of RuS_(2) were investigated.The influence of the metallic Ru surface morphology prior to sulfurization on the reaction between Ru and H_(2)S was also discussed.To evaluate the potential of using RuS_(2) as a photodetector,a photodetector was fabricated by forming electrodes on RuS_(2) to measure its photocurrent under near-infrared light.Thus,RuS_(2) was proven to exhibit a short response time(59μs)and generate a photocurrent of 84 nA under near-infrared light at 940 nm.展开更多
基金Project supported by the Nanoscience Foundation of Shanghai,China (Grant Nos. 0852nm07000 and 0952nm07000)the National Natural Science Foundation of China (Grant No. 10804084)the National Science & Technology Support Project (Grant No. 2006BAF06B08)
文摘This paper presents the experimental progress of laser-focused Cr atomic deposition and the experimental condition. The result is an accurate array of lines with a periodicity of 212.8±0.2 nm and mean full-width at half maximum as approximately 95 nm. Surface growth in laser-focused Cr atomic deposition is modeled and studied by kinetic Monte Carlo simulation including two events： the one is that atom trajectories in laser standing wave are simulated with the semiclassical equations of motion to obtain the deposition position; the other is that adatom diffuses by considering two major diffusion processes, namely, terrace diffusion and step-edge descending. Comparing with experimental results （Anderson W R, Bradley C C, McClelland J J and Celotta R J 1999 Phys. Rev. A 59 2476）, it finds that the simulated trend of dependence on feature width is in agreement with the power of standing wave, the other two simulated trends are the same in the initial stage. These results demonstrate that some surface diffusion processes play important role in feature width broadening. Numerical result also shows that high incoming beam flux of atoms deposited redounds to decrease the distance between adatoms which can diffuse to minimize the feature width and enhance the contrast.
基金supported by the Samsung Electronics Co.,Ltd.(ISO230414-05954-01)Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(NRF2021R1A6A1A03039981)+2 种基金the Korea Institute for Advancement of Technology(KIAT)Grant,funded by the Korea Government(MOTIE)(P0023703,HRD Program for Industrial Innovation)The computations were performed at the Korea Institute of Science and Technology Information(KISTI)National Supercomputing Center(KSC-2024-CRE-0316)the UNIST Supercomputing Center。
文摘Atomic layer deposition(ALD)is extensively used to fabricate doped dielectrics due to its ability to deposit conformal films with atomic-scale thickness control.Al-doped TiO_(2)(ATO)is a promising high-k dielectric for dynamic random access memory(DRAM)applications,offering a high dielectric constant with a remarkable leakage-lowering effect by Al acceptor doping.However,ATO fabrication via conventional supercycle-based ALD suffers from severe crystallinity loss during the growth of TiO_(2) upon Al doping owing to the dopant-induced lattice disorder.In addition,Al doping cannot reduce any inherent O vacancies(V_(O))of TiO_(2),although the original purpose of doping was to address the n-type nature caused by V_(O).To resolve these limitations,we propose a single-step,in-situ Ar/O_(2) post-doping plasma(PDP)process immediately after the Al dopant incorporation.Using the PDP process,simultaneous atomic-scale dopant migration-mediated crystallization and V_(O) annihilation were successfully initiated.Thus,the surface concentration of the dopant decreased,reducing the dopant-induced lattice distortion,while promoting the highly crystallized seed layer-like surface.Consequently,strong rutile-phase recovery was accompanied by enhanced lattice-matched growth.In addition,the PDP process significantly lowers the V_(O)-to-lattice oxygen ratio by facilitating the recombination between reactive O species and V_(O),increasing the corresponding 0.4 e V of conduction band offset(CBO).Despite the common trade-off between the dielectric constant and leakage,the Pt/PDP-ATO/Ru capacitor exhibited a simultaneous 30%increase in dielectric constant and up to a 1.6-order reduction in leakage current density.
基金supported by National Research Foundation of Korea(NRF)funded by Ministry of Science and ICT(MSIT)(No.RS-2023-00260527,RS-2024-00407282,RS-2025-00557667)supported by Hanyang University Industry-University Cooperation Foundation(No.202400000003943)supported by Korea Planning&Evaluation Institute of Industrial Technology(KEIT)funded by South Korean Ministry of Trade,Industry and Energy(MOTIE)(No.RS-2025-25454815,RS-2025-02308064,20017382)。
文摘Oxide semiconductors(OSs),introduced by the Hosono group in the early 2000s,have evolved from display backplane materials to promising candidates for advanced memory and logic devices.The exceptionally low leakage current of OSs and compatibility with three-dimensional(3D)architectures have recently sparked renewed interest in their use in semiconductor applications.This review begins by exploring the unique material properties of OSs,which fundamentally originate from their distinct electronic band structure.Subsequently,we focus on atomic layer deposition(ALD),a core technique for growing excellent OS films,covering both basic and advanced processes compatible with 3D scaling.The basic surface reaction mechanisms—adsorption and reaction—and their roles in film growth are introduced.Furthermore,material design strategies,such as cation selection,crystallinity control,anion doping,and heterostructure engineering,are discussed.We also highlight challenges in memory applications,including contact resistance,hydrogen instability,and lack of p-type materials,and discuss the feasibility of ALD-grown OSs as potential solutions.Lastly,we provide an outlook on the role of ALD-grown OSs in memory technologies.This review bridges material fundamentals and device-level requirements,offering a comprehensive perspective on the potential of ALD-driven OSs for next-generation semiconductor memory devices.
文摘Broadband transparent films play a pivotal role in various applications such as lenses and solar cells,particularly porous structured transparent films exhibit significant potential.This study investigates a porous SiO_(2) refractive index gradient anti-reflective film prepared by atomic layer deposition(ALD).A porous SiO_(2) film with gradual porosity was obtained by phosphoric acid etching of Al_(2)O_(3)/SiO_(2) multilayers with gradient Al2O3 ratios,achieving a gradual decrease in refractive index from the substrate to the surface.The film exhibited an average transmittance as high as 97.8%within the wavelength range from 320 nm to 1200 nm.The environmental adaptability was further enhanced by surface modification using rare earth oxide(REO)La_(2)O_(3),resulting in formation of a lotus leaf-like structure and achieving a water contact angle of 100.0°.These data proved that the modification significantly improved hydrophobic self-cleaning capability while maintaining exceptional transparency of the film.The surface structure of the modified film remained undamaged even after undergoing wipe testing,demonstrating its excellent surface durability.
基金supported by the National Natural Science Foundation of China(Nos.U21A2054,21905007)the Key Discipline of Materials Science and Engineering,Bureau of Education of Guangzhou(Grant No.202255464).
文摘The bismuth-telluride-based alloy is the only thermoelectric material commercialized for the applications of refrigeration and energy harvesting,but its low cost-effectiveness severely restricts its large-scale ap-plication.The introduction of a porous structure in bulk thermoelectric materials has been theoretically proven to effectively reduce thermal conductivity and cost.However,the electrical properties of highly porous materials are considerably suppressed due to the strong carrier scattering at the interface be-tween the matrix and pores,ultimately leading to decreased figure of merit,ZT.Here,we use an atomic layer deposition strategy to introduce some hollow glass bubbles with nano-oxide layers into commercial Bi_(0.5)Sb_(1.5)Te_(3)for preparing high-performance porous thermoelectric materials.Experimental results indi-cate that the nano-oxide layers weaken carrier scattering at the interface between pores and matrix while maintaining high-strength phonon scattering,thereby optimizing carrier/phonon transport behaviors,and effectively increasing the ZT by 23.2%(from 0.99 to 1.22 at 350 K).Besides,our strategy has excellent universality confirmed by its effectiveness in improving the ZT of Bi_(2)Te_(2.7)Se_(0.3),therefore demonstrating great potential for developing low-cost and high-performance thermoelectric materials.
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Ministry of Science and ICT(Nos.2022R1A2B5B02002413 and 2022R1A4A1031182)supported by the Next-Generation Intelligence Semiconductor R&D Program through the Korea Planning&Evaluation Institute of Industrial Technology(KEIT)funded by the Ministry of Trade,Industry,and Energy(MOTIE)of Korea(No.20023574).
文摘With the increase in the demand for wearable devices, temperature-sensing capability is an essential function for flexible and transparent applications. Particularly, the long-term stability of a device is highly desirable for use in daily life. In this study, a flexible and transparent self-powered temperature sensor with remarkable air stability was developed by employing a one-atom-thick monolayer graphene encapsulated with an extremely thin metal oxide layer. Graphene thermocouples were constructed by inducing p- and n-type doping on a high-quality monolayer graphene placed on a transparent polymer film. The entire graphene film was treated by a modulated oxygen plasma, which induced p-type doping with minimal defects on graphene. Half of the graphene was coated with polyethylenimine to form n-type graphene. The graphene p–n junction was encapsulated with a 14-nm-thick ultrathin Al_(2)O_(3) using atomic layer deposition (ALD). The graphene thermocouple exhibited a high Seebeck coefficient of 81.6 ± 2.4 µV/K, high linearity with a coefficient of determination of 0.999, rapid response with a time constant of 0.59 s, low thermal hysteresis, and wide operating temperature range. Owing to the ALD-Al_(2)O_(3) layer, the graphene thermocouple exhibited exceptional air stability, maintaining the Seebeck coefficient for 1028 days. Furthermore, the ultimate thinness of the graphene thermocouple rendered it with an extreme optical transmittance of 94.8 % at a wavelength of 550 nm and a small critical bending radius of 5.71 mm.
基金the European Union,the SOLiD project(grant agreement no.101069505),for the financial support。
文摘LiNi_(0.8)Mn_(0.1)Co_(0.1)O_(2)(NMC811)is an attractive material for high-energy-density Li-ion batteries in electric vehicles.However,it suffers from rapid capacity fading.Previous studies have shown that tuning the positive electrode material via atomic layer deposition(ALD)can enhance the electrochemical performance of the material.In this article,we introduce a novel coating method using gaseous precursors in an ALD reactor,where an AlO_(x)layer is deposited directly on the surface of the NMC811 precursor,followed by lithiation.The AlO_(x)coating is applied to the NMC811 powder substrate by exposing it to gas-phase precursors,using a conventional ALD and simplified ALD(chemical vapor deposition-like)method.It is observed that the novel methods lead to the incorporation of Al as a dopant within the bulk of NMC811,rather than forming a conformal AlO_(x)coating,after the final lithiation step.The optimized procedures result in positive electrode materials with higher capacity and enhanced cycling stability in both half-cell and full-cell configurations.Doping or coating was shown to mitigate transition metal dissolution,reduce side reactions between the active material and electrolyte,and improve structural stability.
基金supported by the National Natural Science Foundation of China(21808214)Research Project Supported by Shanxi Scholarship Council of China(2023-126)Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province(20220013)。
文摘Normally,a transparent inert film is coated on the surface of TiO_(2) particles to enhance the weatherability of the pigment.Liquid-phase coating process is mainly used in industry,which difficult to get really uniform films.This work combining nanoparticle fluidization technology with atomic layer deposition(ALD) technology to achieve precise surface modification of a large number of micro-nano particles.First,we explored the fluidization characteristics of TiO_(2) nanoparticles in a home-made atmospheric fluidized bed ALD reactor(FB-ALD) to ensure the uniform fluidization of a large number of nanoparticles.Then TiCl_(4) and H_(2)O were used as precursors to deposit amorphous TiO_(2) films on the surface of TiO_(2) nanoparticles at 80℃ under atmospheric pressure,and the growth per cycle was about 0.109 nm per cycle.After 30 ALD cycles,the film thickness was about 3.1 nm,which could almost fully suppress the photocatalytic activity of TiO_(2).Compared with other traditional coating materials,amorphous TiO_(2) has higher light refractive index,and realizes the suppression of the photocatalytic activity of TiO_(2) without introducing other substances,demonstrating greater application potential in TiO_(2) pigment coating field.The process is a gas-phase coating method,which is efficient,no waste water,and easy to scale up.This work shown the excellent property of interface engineering in improving pigment weatherability and can also provide guidance for the nanoparticle surface modification.
基金supported by the Natural Science Foundation of Ningbo,China(2022J149)the Natural Science Foundation of Zhejiang Province,China(LY22E020010,LTGS24B030002)+1 种基金the Ningbo Science and Technology Project,China(2022-DST-004,2022A-230G,2024Z242)the National Key Research and Development Program of China,China(2021YFF0500501)。
文摘Atomic layer deposition(ALD)has driven significant advancements in photovoltaic technologies by enabling the development of interlayers that improve both the efficiency and stability of devices.This review traces the evolution of ALD interlayers across various photovoltaic technologies,starting with early silicon solar cells and progressing into a variety of thin-film solar cells.We then delve into the role of ALD in state-of-the-art single-junction perovskite solar cells,particularly in optimizing the critical interfaces of perovskites/charge-transporting layers/-electrodes.Apart from that,we screen the functionality of ALD processing,which consists of reducing surface/interfacial defects and thus mitigating energy loss.Particularly,it enables efficient stacking of multiple thin layers,making a variety of tandem solar cells possible(silicon/perovskite,etc.)for higher efficiency.Moreover,the ALDprocessed interlayer prevents the ion migration between metals and perovskites,inhibiting the inter-diffusioninduced degradation of devices.Despite ALD technology extensively elevating the performance of above conventional/emerging solar cells,key challenges such as precursor flammability,cross-contamination during processing,and low deposition pace persist.We go over these challenges and expect our comprehensive overview of ALD techniques could shed light on pushing the envelope of photovoltaic efficiency.
基金supported by the National Natural Science Foundation of China(21872160,21802094,21673269)the National Science Fund for Distinguished Young Scholars(21825204)+1 种基金the National Key R&D Program of China(2017YFA0700101)the Natural Science Basic Research Plan in Shaanxi Province of China(2018JQ2038)~~
文摘Electrocatalysis is a promising approach to clean energy conversion due to its high efficiency and low environmental pollution. Noble metal materials have been studied to show high activity toward electrocatalyltic reactions, although such applications remain restricted by the high cost and poor durability of the noble metals. By precisely adjusting the catalyst composition, size, and structure, electrocatalysts with excellent performance can be obtained. Atomic layer deposition(ALD) is a technique used to produce ultrathin films and ultrafine nanoparticles at the atomic level. It possesses unique advantages for the controllable design and synthesis of electrocatalysts. Furthermore, the homogenous composition and structure of the electrocatalysts prepared by ALD favor the exploration of structure-reactivity relationships and catalytic mechanisms. In this review, the mechanism, characteristics, and advantages of ALD in fabricating nanostructures are introduced first. Subsequently, the problems associated with existing electrocatalysts and a series of recently developed ALD strategies to enhance the activity and durability of electrocatalysts are presented. For example, the deposition of ultrafine Pt nanoparticles to increase the utilization and activity of Pt, fabrication of core–shell, overcoat, nanotrap, and other novel structures to protect the noble-metal nanoparticles and enhance the catalyst stability. In addition, ALD developments in synthesizing non-noble metallic electrocatalysts are summarized and discussed. Finally, based on the current studies, an outlook for the ALD application in the design and synthesis of electrocatalysts is presented.
基金financially supported by the National Natural Science Foundation of China(No.51972045,5197021414)the Fundamental Research Funds for the Chinese Central Universities,China(No.ZYGX2019J025)+4 种基金Sichuan Science and Technology Program(No.2020JDRC0015 and No.2020JDRC0045)Sichuan Science and Technology Innovation Talent Project(No.2021JDRC0021)the Vice-Chancellor fellowship scheme at RMIT Universitythe RMIT Micro Nano Research Facility(MNRF)in the Victorian node of the Australian National Fabrication Facility(ANFF)the RMIT Microscopy and Microanalysis Facility(RMMF)to support this work。
文摘Developing highly efficient magnetic microwave absorb-ers(MAs)is crucial,and yet challenging for anti-corrosion properties in extremely humid and salt-induced foggy environments.Herein,a dual-oxide shell of ZnO/Al_(2)O_(3) as a robust barrier to FeSiAl core is introduced to mitigate corrosion resistance.The FeSiAl@ZnO@Al_(2)O_(3) layer by layer hybrid structure is realized with atomic-scale precision through the atomic layer deposition technique.Owing to the unique hybrid structure,the FeSiAl@ZnO@Al_(2)O_(3) exhibits record-high micro-wave absorbing performance in low-frequency bands covering L and S bands with a minimum reflection loss(RLmin)of-50.6 dB at 3.4 GHz.Compared with pure FeSiAl(RLmin of-13.5 dB,a bandwidth of 0.5 GHz),the RLmin value and effective bandwidth of this designed novel absorber increased up to~3.7 and~3 times,respectively.Fur-thermore,the inert ceramic dual-shells have improved 9.0 times the anti-corrosion property of FeSiAl core by multistage barriers towards corrosive medium and obstruction of the electric circuit.This is attributed to the large charge transfer resistance,increased impedance modulus|Z|0.01 Hz,and frequency time constant of FeSiAl@ZnO@Al_(2)O_(3).The research demonstrates a promising platform toward the design of next-generation MAs with improved anti-corrosion properties.
基金supported by the Natural Science and Engineering Research Council of Canada (NSERC)the Canada Research Chair Program (CRC) and the University of Western Ontario (UWO)
文摘Noble single‐atom catalysts have rapidly been attracting attention due to their unique catalytic properties and maximized utilization.Atomic layer deposition(ALD)is an emerging powerful technique for large‐scale synthesis of stable single atom.In this review,we summarize recent developments of single atom synthesized by ALD as well as explore future research direction and trends.
基金supported by the U.S. Department of Energy, Office of Science, and Office of the Basic Energy Sciences, under Contract DE-AC-02-06CH11357~~
文摘Atomic layer deposition(ALD)attracts great attention nowadays due to its ability for designing and modifying catalytic systems at the molecular level.There are several reported review papers published recently discussing this technique in catalysis.However,the mechanism on how the deposited materials improve the catalyst stability and tune the reaction selectivity is still unclear.Herein,catalytic systems created via ALD on stepwise preparation and/or modification under self-limiting reaction conditions are summarized.The effects of deposited materials in terms of electronic/geometry modification over the catalytic nanoparticles(NPs)are discussed.These effects explain the mechanism of the catalytic stability improvement and the selectivity modification.The unique properties of ALD for designing new catalytic systems are further investigated for building up photocatalytic reaction nanobowls,tandem catalyst and bi-active-component metallic catalytic systems.
基金supported by NSFC(22175005)Guangdong Basic and Applied Basic Research Foundation(2020B1515120039)+1 种基金Shenzhen Fundamental Research Program(JCYJ20200109110628172,GXWD20201231165807007-20200802205241003)Guangdong Technology Center for Oxide Semiconductor Devices and ICs。
文摘Atomic layer deposition(ALD)has become an indispensable thin-film technology in the contemporary microelectronics industry.The unique self-limited layer-by-layer growth feature of ALD has outstood this technology to deposit highly uniform conformal pinhole-free thin films with angstrom-level thickness control,particularly on 3D topologies.Over the years,the ALD technology has enabled not only the successful downscaling of the microelectronic devices but also numerous novel 3D device structures.As ALD is essentially a variant of chemical vapor deposition,a comprehensive understanding of the involved chemistry is of crucial importance to further develop and utilize this technology.To this end,we,in this review,focus on the surface chemistry and precursor chemistry aspects of ALD.We first review the surface chemistry of the gas–solid ALD reactions and elaborately discuss the associated mechanisms for the film growth;then,we review the ALD precursor chemistry by comparatively discussing the precursors that have been commonly used in the ALD processes;and finally,we selectively present a few newly-emerged applications of ALD in microelectronics,followed by our perspective on the future of the ALD technology.
基金sponsored by the National Natural Science Foundation of China (Nos. 51402190, 61574091)Shanghai Sailing Program (18YF1427800)the special funds for theoretical physics of the National Natural Science Foundation of China (No. 11747029)
文摘Photoanodes based on In_2S_3/ZnO heterojunction nanosheet arrays(NSAs) have been fabricated by atomic layer deposition of ZnO over In_2S_3 NSAs, which were in situ grown on fluorine-doped tin oxide glasses via a facile solvothermal process. The as-prepared photoanodes show dramatically enhanced performance for photoelectrochemical(PEC) water splitting, compared to single semiconductor counterparts. The optical and PEC properties of In_2S_3/ZnO NSAs have been optimized by modulating the thickness of the Zn O overlayer. After pairing with ZnO, the NSAs exhibit a broadened absorption range and an increased light absorptance over a wide wavelength region of 250–850 nm. The optimized sample of In_2S_3/ZnO-50 NSAs shows a photocurrent density of 1.642 m A cm^(-2)(1.5 V vs. RHE) and an incident photonto-current efficiency of 27.64% at 380 nm(1.23 V vs.RHE), which are 70 and 116 times higher than those of the pristine In_2S_3 NSAs, respectively. A detailed energy band edge analysis reveals the type-II band alignment of the In_2S_3/ZnO heterojunction, which enables efficient separation and collection of photogenerated carriers,especially with the assistance of positive bias potential, and then results in the significantly increased PEC activity.
基金Financial supports from the Jiangsu Natural Science Foundation(BK20190677)National Natural Science Foundation of China(21908096)+2 种基金Scientific Research Foundation of Chuzhou University(2020qd06)support from the Program of Excellent Innovation Teams of Jiangsu Higher Education Institutionsthe Project of Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)。
文摘Chromium(Cr)is a common heavy metal that has severe impacts on the ecosystem and human health.Capacitive deionization(CDI)is an environment-friendly and energy-efficient electrochemical purification technology to remove Cr from polluted water.The performance of CDI systems relies primarily on the properties of electrodes.Carbon-nanotubes(CNTs)membranes are promising candidates in creating advanced CDI electrodes and processes.However,the low electrosorption capacity and high hydrophobicity of CNTs greatly impede their applications in water systems.In this study,we employ atomic layer deposition(ALD)to deposit TiO_(2) nanoparticulates on CNTs membranes for preparing electrodes with hydrophilicity.The TiO_(2)-deposited CNTs membranes display preferable electrosorption performance and reusability in CDI processes after only 20 ALD cycles deposition.The total Cr and Cr(VI)removal efficiencies are significantly improved to 92.1%and 93.3%,respectively.This work demonstrates that ALD is a highly controllable and simple method to produce advanced CDI electrodes,and broadens the application of metal oxide/carbon composites in the electrochemical processes.
基金supported by the National Research Foundation of Korea (NRF) funded by the Ministry of Science and ICT (NRF-2020M3H4A3081867)the industry technology R&D program (20006400) funded by the Ministry of Trade,Industry and Energy (MOTIE, Korea)+2 种基金the project number 20010402 funded by the Ministry of Trade,Industry and Energy (MOTIE, Korea)the Industry Technology R&D program (#20010371) funded by the Ministry of Trade,Industry and Energy (MOTIE, Republic of Korea)the Technology Innovation Program (20017382) funded By the Ministryof Trade,Industry and Energy (MOTIE, Korea)
文摘Since the first report of amorphous In–Ga–Zn–O based thin film transistors,interest in oxide semiconductors has grown.They offer high mobility,low off-current,low process temperature,and wide flexibility for compositions and processes.Unfortunately,depositing oxide semiconductors using conventional processes like physical vapor deposition leads to problematic issues,especially for high-resolution displays and highly integrated memory devices.Conventional approaches have limited process flexibility and poor conformality on structured surfaces.Atomic layer deposition(ALD)is an advanced technique which can provide conformal,thickness-controlled,and high-quality thin film deposition.Accordingly,studies on ALD based oxide semiconductors have dramatically increased recently.Even so,the relationships between the film properties of ALD-oxide semiconductors and the main variables associated with deposition are still poorly understood,as are many issues related to applications.In this review,to introduce ALD-oxide semiconductors,we provide:(a)a brief summary of the history and importance of ALD-based oxide semiconductors in industry,(b)a discussion of the benefits of ALD for oxide semiconductor deposition(in-situ composition control in vertical distribution/vertical structure engineering/chemical reaction and film properties/insulator and interface engineering),and(c)an explanation of the challenging issues of scaling oxide semiconductors and ALD for industrial applications.This review provides valuable perspectives for researchers who have interest in semiconductor materials and electronic device applications,and the reasons ALD is important to applications of oxide semiconductors.
基金financially supported by the National Natural Science Foundation of China (Nos. 61971252 and51972182)the Shandong Provincial Natural Science Foundation (ZR2020JQ27 and ZR2021YQ42)the Youth Innovation Team Project of Shandong Provincial Education Department (2020KJN015)。
文摘Atomic layer deposition(ALD) is a versatile technique to deposit metals and metal oxide sensing materials at the atomic scale to achieve improved sensor functions. This article reviews metals and metal oxide semiconductor(MOS) heterostructures for gas sensing applications in which at least one of the preparation steps is carried out by ALD. In particular, three types of MOS-based heterostructures synthesized by ALD are discussed, including ALD of metal catalysts on MOS, ALD of metal oxides on MOS and MOS core–shell(C–S) heterostructures.The gas sensing performances of these heterostructures are carefully analyzed and discussed.Finally, the further developments required and the challenges faced by ALD for the synthesis of MOS gas sensing materials are discussed.
文摘Quantum dots(QDs)are promising candidates for the next-generation optical and electronic devices due to the outstanding photoluminance efficiency,tunable bandgap and facile solution synthesis.Nevertheless,the limited optoelectronic performance and poor lifetime of QDs devices hinder their further applications.As a gas-phase surface treatment method,atomic layer deposition(ALD)has shown the potential in QDs surface modification and device construction owing to the atomic-level control and excellent uniformity/conformality.In this perspective,the attempts to utilize ALD techniques in QDs modification to improve the photoluminance efficiency,stability,carrier mobility,as well as interfacial carrier utilization are introduced.ALD proves to be successful in the photoluminance quantum yield(PLQY)enhancement due to the elimination of QDs surface dangling bonds and defects.The QDs stability and devices lifetime are improved greatly through the introduction of ALD barrier layers.Furthermore,the carrier transport is ameliorated efficiently by infilling interstitial spaces during ALD process.Attributed to the ultra-thin and dense coating on the interface,the improvement on optoelectronic performance is achieved.Finally,the challenges of ALD applications in QDs at present and several prospects including ALD process optimization,in-situ characterization and computational simulations are proposed.
基金supported by TANAKA Kikinzoku Kogyo K.K.Also by the Basic Science Research Program through the National Research Foundation of Korea(NRF)funded by the Ministry of Education(No.NRF-2021R1I1A1A01057933)。
文摘The chalcogenides of platinum-group metals(PGMs)have been known to be present in minerals and the intermediate products of refining.Over recent years,their applications in various fields,including catalysis,have been explored.Given that certain PGM chalcogenides behave as compound semiconductors,they can be used as materials for photodetectors.In this study,RuS_(2),featuring a bandgap suitable for near-infrared photodetectors,was prepared by forming Ru on a SiO_(2)/Si substrate via the atomic layer deposition method using[Ru(TMM)(CO)_(3)]as the precursor.Annealing was conducted at 800℃ for 1 h under H_(2)S flow.High-resolution transmission electron microscopy(HRTEM)and X-ray diffraction(XRD)analysis clearly confirmed that the as-deposited hexagonal close-packed(hcp)Ru transformed to cubic RuS_(2) after post-annealing.The surface morphologies,chemical states,and electrical and optical properties of RuS_(2) were investigated.The influence of the metallic Ru surface morphology prior to sulfurization on the reaction between Ru and H_(2)S was also discussed.To evaluate the potential of using RuS_(2) as a photodetector,a photodetector was fabricated by forming electrodes on RuS_(2) to measure its photocurrent under near-infrared light.Thus,RuS_(2) was proven to exhibit a short response time(59μs)and generate a photocurrent of 84 nA under near-infrared light at 940 nm.
