Al2O3 Interface Research Articles

On the thinnest Al2O3 interlayers in Al‐based nanolaminates to enhance strength, and the role of constraint

Physical vapour deposition combined with atomic layer deposition was exploited to design a model system of UFG aluminium with a narrow grain size and shape distribution, including two types of interfaces (Al-Al & Al-Al2O3), with Al-Al grain boundary orientations exclusively parallel to the loading axis. This enabled isolated study of the strengthening mechanisms that ultrathin oxide layers would provide in a metal multilayer structure. The Al/Al2O3 crystalline/amorphous multilayers with 240 nm metal layers and oxide thicknesses in the range <1 nm–12 nm (i.e. to below the natural oxidation thickness), were microcompressed, yielding a pseudo-macroscopic yield strength of 532 MPa – over 100 MPa higher than the literature-conforming oxide-free reference. The homogenous co-deformation of the structure, with barrelling of the individual metal layers at the micropillar edges, results from the high bonding strength of the metal with its native oxide, meaning no failure or sliding at the interface, unlike previous Al/ceramic multilayer studies. Only the thicker (≥5 nm) oxide layers fractured in-plane: at locations coincident with vertical Al-Al grain boundaries. An analysis of contributions to the strength of these crystalline/amorphous metal/ceramic hybrid multilayers is carried out, identifying the Al-Al2O3 interface to be the crucial factor, rather than the in-plane tensile stiffness and considerable plasticity of ALD Al2O3 itself. The strengthening effect of the oxide layer was effective down to a layer thickness of just 0.5 nm.

Near-infrared photodetector based on MoS2 QDs/GaAs heterojunction with an Al2O3 interface passivation layer

Two-dimensional (2D) materials have attracted many attentions since they have been discovered. In recent years, various photodetectors made of 2D materials have been continuously reported. In this study, a near-infrared photodetector is fabricated by consisting of a heterojunction of MoS2 quantum dots (QDs) and p-type GaAs substrate. In the subsequent test, it is found that the device has response to three wavelengths of 808 nm, 1064 nm, and 1310 nm, where the 1064 nm band response is the highest. Further test and comparison also find that the insertion of Al2O3 passivation layer with 2 nm thickness at the interface between MoS2 QDs and GaAs and thermal annealing of MoS2 QDs can improve the performance of the device. Finally, under the bias condition of −0.1 V, the response can reach 143.2 mA⋅W−1, and the detection rate is 3.32 × 1010 cm⋅Hz1/2⋅W−1. Under the signal frequency of 2 kHz, the rise time and fall time of the device are 12 μs and 32 μs, respectively; at 4 kHz, the low response time of 24 μs and 74 μs can be achieved, respectively.

Microstructure evolution and interfacial bonding mechanisms of ultrasonically soldered sapphire/Al dissimilar joints using Sn-based solders

Sapphire and 5A06 Al were ultrasonically soldered with Sn9Zn, SAC305 alloy solders and NiCu alloy foam added Sn-based composite solders, respectively. The microstructure and mechanical properties of joints were investigated and the interfacial bonding mechanism was analyzed. Cracks were observed at the sapphire/Sn matrix interface in joints soldered with alloy solders, which were disappeared in the joints soldered with composite solders. In the joint using NiCu–Sn9Zn composite solder, the solder seam was uneven and Al3Ni intermetallic compound (IMC) layer was formed on the surface of NiCu alloy skeletons. While in the joint using NiCu-SAC305 composite solder, fine particles of (Ni,Zn)3Sn4 were largely formed and homogeneously distributed in the solder seam. An amorphous Al2O3 transition layer was formed at the sapphire/Sn matrix interface, and Zn enrichment was found at the Sn matrix/amorphous Al2O3 interface. The action mechanism of Zn was analyzed by first-principles calculation. The joints soldered with NiCu-SAC305 composite solder exhibited the highest shear strength of 74.42 MPa, the shearing failure mainly happened in the soldering seam.

Microstructure and Modifications of Cu/Al2O3 Interfaces

Abstract A combined approach of high-resolution transmission electron microscopy and electron energy-loss near-edge structure studies was employed to determine the atomic structure and bonding mechanisms at Cu/Al2O3 interfaces in dependence on the α-Al2O3 substrate orientation. The investigated specimens were prepared by molecular beam epitaxy using ultrahigh vacuum conditions, which led to atomically abrupt interfaces. The results show that intermetallic Cu–Al bonds occur at the investigated Cu/ (112̅0)Al2O3 interface, while ionic-covalent bonding contributions are observed at the Cu/(0001)Al2O3 interface. The interfacial microstructure of diffusion-bonded Cu/ (0001)Al2O3 samples was changed by annealing treatments under various oxygen partial pressures. Annealing resulted in the formation of a CuAlO2 reaction phase at the interface between Cu and Al2O3.

Adsorption of CO2 with tetraethylammonium glycine ionic liquid modified alumina in the Rotating Adsorption Bed

CO2 capture and reuse have become the crucial task for controlling severe climate changes. Based on the practical application problems related to high viscosity of the ionic liquids (ILs) in the CO2 absorption process, the new adsorbent was obtained by loading the tetraethylammonium glycine (N2222Gly) on millimeter-scale microspheres of alumina (Al2O3) with ultrasonic impregnation-filtration method in this text. The results shown that the N2222Gly was successfully and uniformly loaded on the surface and pore structure of the Al2O3 by the electrostatic interaction between glycine anion and the positively charged Al2O3 interface. The prepared adsorbent (N2222Gly-Al2O3) were filled in the Rotating Adsorption Bed (RAB), and a rapidly updated gas-solid interface area was formed when the RAB was rotating under the drive of the motor. Under the rotating dynamic environment, more active sites of N2222Gly-Al2O3 were exposed to CO2 and the mass transfer effect between gas-solid was effectively enhanced. The adsorption capacity in the RAB was equal to 15.94 mg·g−1, and was about 4.63 mg·g−1 higher than in the fixed bed. In addition, the RAB showed a seductive strengthening effect with the decrease in adsorption capacity of only 14.5% after six desorption operations (much less than the 30.5% decrease in the fixed bed). Interestingly, as a new type of adsorption device, the RAB enhanced the internal and external diffusion rates of the adsorption process, providing a new idea for the effective adsorption of CO2 at low partial pressure with presence of the N2222Gly-Al2O3.

Epitaxial growth and thermoelectric properties of Mg3Bi2 thin films deposited by magnetron sputtering

Mg3Sb2-based thermoelectric materials attract attention for applications near room temperature. Here, Mg-Bi films were synthesized using magnetron sputtering at deposition temperatures from room temperature to 400 °C. Single-phase Mg3Bi2 thin films were grown on c-plane-oriented sapphire and Si(100) substrates at a low deposition temperature of 200 °C. The Mg3Bi2 films grew epitaxially on c-sapphire and fiber-textured on Si(100). The orientation relationships for the Mg3Bi2 film with respect to the c-sapphire substrate are (0001) Mg3Bi2‖(0001) Al2O3 and [112¯0] Mg3Bi2‖[112¯0] Al2O3. The observed epitaxy is consistent with the relatively high work of separation, calculated by the density functional theory, of 6.92 J m−2 for the Mg3Bi2 (0001)/Al2O3 (0001) interface. Mg3Bi2 films exhibited an in-plane electrical resistivity of 34 μΩ m and a Seebeck coefficient of +82.5 μV K−1, yielding a thermoelectric power factor of 200 μW m−1 K−2 near room temperature.

Self-powered near-infrared MoS2/n-Si photodetectors with Al2O3 interface passivation

Due to their excellent light absorption and photovoltaic effects, transition metal dichalcogenide-based heterojunctions have been widely investigated as materials for optoelectronic devices. This work presented a MoS2 film preparation process using electron beam evaporated MoO3 films as the precursor layer. The prepared MoS2 film was used in the self-powered MoS2/Al2O3/n-Si photodetector, which showed high responsivity (1.15 A W−1), normalized detectivity (1.28 × 1011 Hz1/2 cm/W) and photoresponse (τr = 28 μs) without external bias. Besides, the photodetector exhibited a large frequency-photoresponse range (up close to 100 kHz). Moreover, attributed to the excellent MoS2 quality and the effective interface passivation by ALD-deposited Al2O3, the high-speed photoresponse of the photodetector was realized. These results demonstrated the potential of applying MoS2 material prepared from electron beam evaporated MoO3 precursor layers in the high-frequency and fast photoresponse photodetectors.

Strengthening and toughening B4C/Al composites via optimizing the Al2O3 distribution during hot rolling

B4C/Al composites with a high B4C content of 30 wt% were successfully fabricated by hot pressing sintering followed by hot rolling. The influence of hot rolling on the microstructure, mechanical properties, anisotropy and the interfacial conditions of the B4C/Al composites were systematically investigated. The improvement of the interfacial Al2O3 nanoparticles distribution during hot rolling increased both the strength and ductility. After sintering of B4C/Al composites, some Al2O3 nanoparticles aggregated together at the interface between B4C and Al matrix, lowering the interface bonding strength between B4C and Al matrix. The Al2O3 nanoparticles dispersed into the Al grain interior after rolling, leading to a well bonding interface between B4C particles and the Al matrix. In addition, the dispersion of Al2O3 nanoparticles into the Al grain interior contributed to the strength through Orowan strengthening and ductility through the enhancement of dislocation storage ability. The strengthening and toughening mechanisms of the composites are discussed in detail.

Interface doping of zinc oxide nanorods

The effect of an increase in the electrical conductivity of a system of zinc oxide nanorods by a factor of 105 during atomic layer deposition of a thin dielectric layer of aluminum oxide was found. It is shown that a change in the electrical conductivity of zinc oxide during atomic layer deposition of aluminum oxide on the surface is also observed for thin polycrystalline layers of zinc oxide. A study of polycrystalline layers of zinc oxide coated with aluminum oxide using ultraviolet and X-ray photoelectron spectroscopy is presented. Based on the results of photoelectron spectroscopy, two main factors for changing the electrical conductivity are proposed, which consist in the formation of a two-dimensional electron gas at the ZnO|Al2O3 interface and doping of the near-surface region of zinc oxide with aluminum atoms. Keywords: nanorods, zinc oxide, aluminum oxide, atomic layer deposition, transparent electrodes, X-ray photoelectron spectroscopy, ultraviolet photoelectron spectroscopy.

Interface Optimization and Transport Modulation of Sm2O3/InP Metal Oxide Semiconductor Capacitors with Atomic Layer Deposition-Derived Laminated Interlayer.

In this paper, the effect of atomic layer deposition-derived laminated interlayer on the interface chemistry and transport characteristics of sputtering-deposited Sm2O3/InP gate stacks have been investigated systematically. Based on X-ray photoelectron spectroscopy (XPS) measurements, it can be noted that ALD-derived Al2O3 interface passivation layer significantly prevents the appearance of substrate diffusion oxides and substantially optimizes gate dielectric performance. The leakage current experimental results confirm that the Sm2O3/Al2O3/InP stacked gate dielectric structure exhibits a lower leakage current density than the other samples, reaching a value of 2.87 × 10−6 A/cm2. In addition, conductivity analysis shows that high-quality metal oxide semiconductor capacitors based on Sm2O3/Al2O3/InP gate stacks have the lowest interfacial density of states (Dit) value of 1.05 × 1013 cm−2 eV−1. The conduction mechanisms of the InP-based MOS capacitors at low temperatures are not yet known, and to further explore the electron transport in InP-based MOS capacitors with different stacked gate dielectric structures, we placed samples for leakage current measurements at low varying temperatures (77–227 K). Based on the measurement results, Sm2O3/Al2O3/InP stacked gate dielectric is a promising candidate for InP-based metal oxide semiconductor field-effect-transistor devices (MOSFET) in the future.

Effect of Native Oxide Layer on Mechanochemical Reaction at the GaN-Al2O3 Interface.

Mechanochemical reactions at the gallium nitride-alumina (GaN–Al2O3) interface at nanoscale offer a significant beneficial reference for the high-efficiency and low-destruction ultra-precision machining on GaN surface. Here, the mechanochemical reactions on oxide-free and oxidized GaN surfaces rubbed by the Al2O3 nanoasperity as a function of the ambient humidity were studied. Experimental results reveal that oxidized GaN exhibits a higher mechanochemical removal rate than that of oxide-free GaN over the relative humidity range of 3–80%. The mechanical activation in the mechanochemical reactions at the GaN–Al2O3 interface is well-described by the mechanically-assisted Arrhenius-type kinetics model. The analysis indicates that less external mechanical activation energy is required to initiate the mechanochemical atomic attrition on the oxidized GaN surface compared with the oxide-free GaN surface. These results may not only gain a deep understanding of the mechanochemical removal mechanism of GaN but also provide the basic knowledge for the optimization of the oxidation-assisted ultra-precision machining.

Spin-coating for fabrication of high-entropy high-k (AlTiVZrHf)Ox films on Si for advanced gate stacks

Spin-coating was performed to fabricate amorphous high-entropy oxide (HEO) (AlTiVZrHf)Ox films on Si substrates. The films were evaluated through X-ray photoelectron spectroscopy and through transmission electron microscopy (TEM)-based energy-dispersive spectroscopy (EDS) mapping, which respectively revealed all constituent elements and the homogenous distributions and no aggregation of those elements. TEM analysis revealed four distinct layers—a crystalline Al metal gate, an amorphous Al2O3 interfacial layer, amorphous (AlTiVZrHf)Ox, and native amorphous SiO2—in a patterned metal–oxide–semiconductor (MOS) gate stack on the Si substrate. The resulting stack exhibited a low leakage current density (JL) and no frequency dispersion in its capacitance–voltage characteristics after undergoing forming gas annealing. The obtained dielectric constant (k ≈ 32) for the HEO film is promising for advanced gate stacks and transistor applications. Although the film exhibited minor nanocrystallinity and the stack exhibited no interfacial Al2O3 layer after rapid thermal annealing at 900 °C, a low JL, distinct layers, and a clearly defined interface between the (AlTiVZrHf)Ox and SiO2 were observed, indicating no substantial diffusion among these layers. EDS mapping revealed the homogenous distribution of each constituent element without aggregation. Medium-entropy-oxide films and their MOS devices were fabricated for comparison; however, they exhibited inferior performance.

Improved performance of Ni/Al2O3 catalyst deriving from the hydrotalcite precursor synthesized on Al2O3 support for dry reforming of methane

Exploiting Ni-based catalysts with excellent catalytic activity and anti-coking ability is significant for dry reforming of CH4 with CO2 (DRM) which is a promising route to CO2 utilization. In this work, the Ni/Al2O3 catalyst with hydrotalcite precursor (NiAl-LDH) was synthesized by a facile in-situ growth method. And the effect of the NiAl-LDH structure on the catalytic activity and anti-coking ability of Ni/Al2O3 catalyst was revealed. The H2-temperature programmed desorption (H2-TPD) revealed that better Ni dispersion and more Ni–Al2O3 interface could be obtained by the NiAl-LDH precursor, which were vital for the activation of CH4 and CO2. Moreover, the NiAl-LDH precursor with non-LDH phase or turbostratic structure was also created by insufficient or extra amount of urea, and the obtained catalysts exhibited a poor catalytic stability, further confirming the importance of the LDH structure. In comparison with the Ni-IMP catalyst prepared by the conventional impregnation method, the CH4 conversion increased by 16% and the carbon deposition decreased by 75% over Ni-6 catalyst with well-organized LDH precursor under the same reaction conditions. Hence, this work represents an important step toward developing Ni-based catalysts with excellent catalytic activity and anti-coking ability for DRM with the LDH precursor.

Impact of gamma-ray irradiation on capacitance–voltage characteristics of Al2O3/GaN MOS diodes with and without post-metallization annealing

Atomic layer deposited Al2O3/GaN metal-oxide-semiconductor (MOS) diodes with and without post-metallization annealing (PMA) were irradiated with gamma-rays. Capacitance–voltage measurements were made before and after irradiation to investigate trap formation in Al2O3 films and interface states between Al2O3 and GaN. Negative flat-band voltage shifts were observed. The flat-band voltage shift depends on the Al2O3 thickness, showing different distributions of gamma-ray-induced positive charges for samples with and without PMA. The interface state density of the PMA sample slightly increased after irradiation, but was lower than that of the sample without PMA before irradiation.

Enhanced High-Frequency Performance of Top-Gated Graphene FETs Due to Substrate- Induced Improvements in Charge Carrier Saturation Velocity

The high-frequency performance of top-gated graphene field-effect transistors (GFETs) depends to a large extent on the saturation velocity of the charge carriers, a velocity limited by inelastic scattering by surface optical phonons from the dielectrics surrounding the channel. In this work, we show that, by simply changing the graphene channel surrounding dielectric with a material having higher optical phonon energy, one could improve the transit frequency and maximum frequency of oscillation of GFETs. We fabricated GFETs on conventional SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Si substrates by adding a thin Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> interfacial buffer layer on top of SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> /Si substrates, a material with about 30% higher optical phonon energy than that of SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , and compared performance with that of GFETs fabricated without adding the interfacial layer. From S-parameter measurements, a transit frequency and a maximum frequency of oscillation of 43 and 46 GHz, respectively, were obtained for GFETs on Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> with 0.5- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> gate length. These values are approximately 30% higher than those for state-of-the-art GFETs of the same gate length on SiO <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> . For relating the improvement of GFET high-frequency performance to improvements in the charge carrier saturation velocity, we used standard methods to extract the charge carrier velocity from the channel transit time. A comparison between two sets of GFETs with and without the interfacial Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> O <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> layer showed that the charge carrier saturation velocity had increased from <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.5\cdot 10^{{7}}$ </tex-math></inline-formula> to <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\cdot 10^{{7}}$ </tex-math></inline-formula> cm/s.

Interface characteristics of β-Ga2O3/Al2O3/Pt capacitors after postmetallization annealing

Interface characteristics of frequency dispersion, flatband voltage (Vfb) shift, fixed charge (QIL), and interface state density (Dit) in β-Ga2O3/Al2O3/Pt capacitors were investigated after postmetallization annealing (PMA) at 300 °C in N2 using a conductance method and a photo-assisted capacitance-voltage technique. After PMA, no frequency dispersion was observed, and the QIL and Dit values related to interface states near the conduction band edge (Ec) were significantly reduced to the ranges of −4 to +1 × 1011 cm−2 and 3 to 8 × 1011 cm−2 eV−1 at Ec − E = 0.4 eV, respectively, in the capacitors subjected to a low postdeposition annealing (PDA) temperature region of 300–600 °C. In contrast, a large frequency dispersion, and high QIL (−2 × 1012 cm−2), and Dit (4–5 × 1012 cm−2 eV−1 at Ec − E = 0.4 eV) of the capacitors with a high PDA temperature region of 700–900 °C remained. This difference is considered to be due to hard structural changes at the multilayer level by the interdiffusion of Ga and Al at the β-Ga2O3/Al2O3 interface caused by PDA above 700 °C. In contrast, the average Dit values due to the electrons deeply trapped below the midgap between 2.6 and 3.3 eV decreased from 2 × 1012 to 1 × 1011 cm−2 eV−1 as the PDA temperature was increased from 300 to 900 °C, respectively, before PMA. No significant change in Dit below the midgap was observed, regardless of the PDA temperature after PMA. Note that the PMA treatment effectively improved only the interface properties near the Ec after treatment in the low PDA temperature region below 600 °C.

Structure and behavior of ZrO2-graphene-ZrO2 stacks

ZrO2-graphene-ZrO2 layered structures were built and their crystallinity was characterized before resistive switching measurements. Thin nanocrystalline ZrO2 dielectric films were grown by atomic layer deposition on chemical vapor deposited graphene. Graphene was transferred, prior to the growth of the ZrO2 overlayer, to the ZrO2 film pre-grown on titanium nitride. Nucleation and growth of the top ZrO2 layer was improved after growing an amorphous Al2O3 interface layer on graphene at lowered temperatures. Studies on resistive switching in such structures revealed that the exploitation of graphene interlayers could modify the operational voltage ranges and somewhat increase the ratio between high and low resistance states.

Interface properties of Ti3SiC2/Al2O3 ceramics: Combined experiments and first-principles calculations

The synthesis, characterization, and first-principles calculations of Ti3SiC2/Al2O3 ceramics were reported. X-ray diffraction measurements showed that the composite ceramics were highly pure. Scanning electron microscopy and transmission electron microscopy were used to characterize the interface information for Ti3SiC2 and Al2O3 crystals. Surface energies and interface properties were calculated using the first-principles method. The results suggested that Ti3SiC2 with Ti terminations and Al2O3 with O terminations are more stable than other terminations crystals. Thus powerful attraction between the coordinatively unsaturated Ti and O atoms on the Ti3SiC2∥Al2O3 interface would result in higher work of adhesion (Wad) and shorter boundary distance, demonstrating the intercrystalline strengthening of Ti3SiC2/Al2O3 composite ceramics.

Achieving Highly Efficient and Stable Quantum Dot Light-Emitting Diodes With Interface Modification

In conventional quantum dot light-emitting diodes (QLEDs), the organic charge transport materials are susceptible to erosion by water and oxygen, which would reduce the efficiency and lifetime of the devices. Herein, we modified the surface of the organic hole transport layer with an ultra-thin Al2O3 layer, which is deposited by using atomic layer deposition technique, to obtain the highly efficient and stable QLEDs. It is indicated that the ultra-thin Al2O3 interlayer plays a significant role in decreasing leakage current, suppressing exciton quenching and passivating the defects. The device with Al2O3 interface modification exhibits the maximum external quantum efficiency (EQE) of 20.8%, current efficiency (CE) of 21.6 cd A−1, and lifetime of 482000 h. In comparison with the control device, the EQE, CE and lifetime are improved by 31%, 32%, and 330%, respectively. The results indicate that the strategy of Al2O3 interface modification could provide an effective way for realizing highly efficiency QLED with long lifetime.

Interface Engineering of CsPbBr3 Nanocrystal Light‐Emitting Diodes via Atomic Layer Deposition

Perovskite nanocrystal (PNC) suffers from solution corrosion and water/oxygen oxidation when used in light‐emitting diodes (LEDs). Atomic layer deposition (ALD) is applied to introduce Al2O3 infilling and interface engineering for the CsPbBr3 nanocrystal emission layers, and the inorganic electron transport layer‐based CsPbBr3–ZnMgO LED device is fabricated. The introduction of Al2O3 ALD layers significantly improves the tolerance of CsPbBr3 PNC thin films to polar solvents ethanol of ZnMgO during spin coating. The operation lifetime of ALD‐treated CsPbBr3 PNC–ZnMgO LED is prolonged to about two orders of magnitude greater than that of the CsPbBr3 PNC‐TPBi LED device with a largely improved external quantum efficiency (EQE) value. Moreover, the infilling of Al2O3 into the CsPbBr3 layer boosts the carrier mobility for more than 40 times inside the light‐emission layer. However, the interfacial carrier transport between different functional layers is hindered by the insulated Al2O3 layer, which provides an effective barrier for excess electron transport. Such a favorable band alignment facilitates the carrier balance of the device and contributes to the improved electroluminescent performance of the device with ALD Al2O3 interface engineering, which is further supported by theoretical device modeling. Herein, a facile method is provided to fabricate PNC‐LED devices with both high efficiency and long‐term lifetime.