Indium Incorporation Research Articles

Manipulating cathode composition to enhance performance of proton-conducting solid oxide fuel cells through indium doping

One current research direction in proton-conducting solid oxide fuel cells (H–SOFCs) focuses on developing triple-phase conducting cathodes. By optimizing the cerium and indium ratio and adjusting the phase composition of barium ferrate cathode materials, improved power density is achieved in single cells with BaCe0.21Fe0.64In0.15O3-δ (BCFI15) as the cathode, reaching a peak power density of 1473 mW cm−2 at 700 °C. Density functional theory calculations (DFT) further support that the incorporation of indium through doping effectively reduces the energy barrier for proton transition, thereby enhancing proton absorption capability and electrochemical reactivity.

Performance improvement of planar silicon nanowire field effect transistors via catalyst atom doping control

Catalytic growth of silicon nanowires (SiNWs), mediated by metallic droplet, provide ideal quasi-1D channels to construct high performance field effect transistor (FET). However, the incorporation of catalytic metal atoms into SiNWs channels has significant impact on the FET characteristics, and thus needs to be better understood and controlled to fulfil its potential for high performance electronics. In this work, we focus on the effect of the incorporation of indium (In) catalytic atoms into planar SiNWs, grown via an in-plane solid-liquid-solid (IPSLS) mechanism, on the FET device performance. It is found that the initial high concentration of p-type In dopants in the as-grown SiNWs led to an equivalent boron (B) doping of 5×1018 cm−3. However, a simple step-wise annealing in oxygen at different temperatures, varied from 620 °C to 920 °C, can help to out-diffuse the dissolved In atoms into the surface SiO2 layer, and reduce the In concentrations down to <5×1017 cm−3, as verified by atom-probe tomography (APT) and four-point-probe measurements. This effective dopant control enables a remarkable device performance improvement of the Schottky barrier FETs, built upon an orderly array of parallel SiNWs of approximately 25 nm in diameter, where the current ratio (Ion/Ioff) has been substantially boosted from 105 to 108, while the subthreshold swing (SS) reduced from 400 mV/dec down to ∼100 mV/dec, with a hole carrier mobility increased from 10 to ∼75 cm2 V−1 s−1 as extracted according to a finite element analysis. These results pave the way for the employment of the catalytic IPSLS SiNWs to serve as high quality 1D channels for high-performance SiNWs-based electronics and sensors.

Crystal Quality and Efficiency Engineering of InGaN‐Based Red Light‐Emitting Diodes

This article is aimed at understanding of the complex design of metalorganic chemical vapour deposition ‐grown InGaN‐based red light‐emitting diode (LED) structure. The contribution of different elements of red LED structure to the stress distribution and threading dislocation density (TDD) evolution is theoretically investigated. For this purpose a self‐consistent modeling of the structure growth process is used, taking into account stress‐modulated indium incorporation, mismatch stress relaxation by threading dislocations and V‐pits, and nucleation of new threading dislocations. The simulation results, consisting of composition, stress, and TDD profiles, are then utilized for modeling of device operation, which allows to analyze contribution of different elements to the heterostructure operation.

Insights into the DFT‐computed electronic and optical properties of binary and doped: Selenide for optoelectronic applications

AbstractThis study investigates the alterations in structural, electronic, and optical characteristics of ZnSe1−x Inx (x = 0%, 12.5%, 25%) employing the framework of density functional theory (DFT), utilizing generalized gradient approximation (GGA) in conjunction with the full‐potential linearized augmented plane wave (FP‐LAPW) approach. The findings reveal that pure ZnSe exhibits a direct bandgap of 1.79 eV at the Γ point, which reduces to 0 eV upon doping with Indium, indicating a transition to metallic characteristics. This change is attributed to the predominant involvement of the d‐orbital of Zn, s‐orbital of Se, and p‐orbitals of Indium in the valence band of ZnSe1−x Inx materials. Conversely, the s‐orbital of Zn predominantly contributes to the conduction band of undoped ZnSe, whereas the d‐orbitals of Indium play a significant role in the conduction band of ZnSe1−x Inx (x = 0%, 12.5%, 25%). Moreover, the study computes other optical parameters, including reflectivity, electron energy loss spectrum, extinction coefficient, refractive index, and absorption coefficient, as functions of photon energy. A notable observation is the considerable rise in the zero‐frequency dielectric constant, ε1(0), which increases from 5.0 in pure ZnSe to 40.0 and 50.0 in Indium‐doped ZnSe, highlighting a significant alteration in electronic properties. Furthermore, optical analyses demonstrate an expansion in the absorption coefficient spectrum, which extends from photon energies of 2.0 eV in pristine ZnSe to begin at 0 eV in Indium‐doped variants, indicating a broadening of the material's capacity to absorb light across a wider spectrum of photon energies. This expansion infers improved light absorption potential, which could be particularly beneficial for the fabrication of light‐emitting modules and solar energy converters. These insights underline the considerable influence that Indium incorporation exerts on the band architecture and optical responses of ZnSe, offering critical directions for the advancement of optoelectronic devices.

Comparative analysis of selective area grown Ga- and N-polar InGaN/GaN nanowires for quantum emitters

In this paper, we report the molecular beam epitaxy-grown InGaN-quantum disks embedded within selective area epitaxy of GaN nanowires with both Ga- and N-polarities. A detailed comparative analysis of these two types of nanostructures is also provided. Compared to Ga-polar nanowires, N-polar nanowires are found to exhibit a higher vertical growth rate, flatter top, and reduced lateral overgrowth. InGaN quantum disk-related optical emission is observed from nanowires with both polarities; however, the N-polar structures inherently emit at longer wavelengths due to higher indium incorporation. Considering that N-polar nanowires offer more compelling geometry control compared to Ga-polar ones, we focus on the theoretical analysis of only N-polar structures to realize high-performance quantum emitters. A single nanowire-level analysis was performed, and the effects of nanowire diameter, taper length, and angle on guided modes, light extraction, and far-field emission were investigated. These findings highlight the importance of tailoring nanowire geometry and eventually optimizing the growth processes of III-nitride nanostructures.

Efficient InGaN‐Based Red Light‐Emitting Diodes by Modulating Trench Defects

AbstractTrench defects in multi‐quantum wells (MQWs) have been considered as flawed structures that severely degraded the internal quantum efficiency (IQE) of light‐emitting diodes (LEDs) in the past. In this research, trench defects are innovatively utilized to enhance the efficiency of red InGaN LEDs. Specifically, dual‐color MQWs structures are applied to modulate trench defects. The upper red MQWs, grown on top of green MQWs with a high density of trench defects, exhibit a significant wavelength redshift of 68 nm and ≈ 6‐fold luminescence enhancement compared to those without intentionally introduced trench defects. Red InGaN LEDs with an IQE of 16.4% are achieved with this epitaxy growth strategy. Such wavelength redshift is attributed to the more indium incorporation due to the strain relaxation effect of trench defects. Moreover, the luminescence enhancement originates from the strong emission of the red MQWs inside trench defects, mainly attributed to strain relaxation and defect shielding by the wide and deep trenches. Achieving red emission by modulating trench defects is simple and reproducible without requiring additional substrate designs, which provides a novel way toward high‐efficiency red InGaN LEDs.

Electrochemistry in Photonic Devices Processing: a Disruptive Approach in GaN Technology

Electrochemistry, except the electrodeposition of metal for making contacts, is rarely represented in microelectronics, despite the many possibilities it may offer like “soft” surface treatments (no surface bombardment, low damage), very sensitive methods (femtoampers sensitivity) and its large compatibility with high aspect ratio structures (TSV Cu filling). Nowadays, the More than Moore law compels researchers to look for other solutions than standard microelectronic processes to reach disruptive solutions: electrochemical processes may provide this new pathway. In that context, our study focuses on III-N material, specifically on GaN porosification through electrochemical anodization for photonic applications. After a study to understand GaN electrochemistry, we will see how new photonic device architectures may arise from the controlled porosification of GaN.Before going towards photonic applications, the understanding of the GaN electrochemical system is required. First we show that the variation of the main electrochemical and material parameters like GaN doping level, anodization potential, and electrolyte composition enables the fine-tuning of the porosity level, pore density, pore size and pore morphology. Then nano-indentation, ellipsometry and reflectometry measurements give us access to a good knowledge of the variation of the Young modulus and refractive index versus porosity level and pore morphology. The measured physico-chemical properties, mechanical as well as optical, of porous GaN eventually paves the way for new device developments.In our talk, we will show how electrochemistry requirements have an impact on the design of the final structure. We will focus on two porous GaN structures built from the previous electrochemical systemic study on GaN thin layers: i) a LED on porous GaN Bragg mirror (DBR) and ii) a relaxed InGaN pseudo-substrate for RGB micro-display applications. LED on DBR: Specifically designed epitaxial stack and technology allow the fabrication of a blue GaN/InGaN based LED structure on a DBR made of alternating porous and dense GaN layers. The optimized one-step electrochemical process results in a very efficient DBR with 99,99% reflectance and a large stop band centered on 460-520 nm. The presence of the porous GaN DBR below the LED stack exalts the photoluminescence and the cathodoluminescence signals compared with standard LEDs grown on bulk substrates. These results open a new field of research regarding the capability of tuning GaN refractive index. Fully relaxed InGaN structure for red light emission: Results on partially or totally relaxed InGaN pseudo-substrate will be presented. The InGaN pseudo-substrate relaxation helps indium incorporation in the overgrown quantum wells and enables light emission in long wavelength towards red. The control of the electrochemical and semi-conductor parameters shows that the relaxation of the III-N structure measured by HR-DRX clearly depends on the porosity level and pore morphology. This means that relaxation can be fine-tuned: that will allow an epitaxial regrowth of micro-LED structures compatible with high indium concentration in the quantum wells and possibly RGB micro-LED fabrication for micro-display applications. In that part, we will demonstrate how electrochemistry associated with microelectronic technology brings a new way of controlling relaxation of InGaN on GaN and how the obtained experimental results are promising for the fabrication of high indium content relaxed structure. Through these two examples, we put in evidence how electrochemistry allows inventing solutions unimaginable with the standard microelectronics processes.

Improving performances of ultra-small size (1–20 μ m) InGaN red micro-LEDs by growing on freestanding GaN substrates

The ultra-small size InGaN red micro-LED has attracted a lot of research interest for AR micro-display applications. However, it still faces the challenge of maintaining the emission wavelength and efficiency that meet the needs of micro-display in small size and high current density. Here, we demonstrate 1–20 μm InGaN red micro-LEDs based on freestanding GaN substrates, showing enhanced indium incorporation compared with those grown on traditional sapphire substrates. For the 1 μm devices, an external quantum efficiency (on-wafer) of 0.86% and a wavelength of 613.6 nm are achieved at a current density of 50 A/cm2. In addition, the emission uniformity of 1 μm array grown on GaN substrates is significantly superior to that grown on sapphire substrates. These results indicate that freestanding GaN substrates are benefits for improving performance of red InGaN micro-LEDs.

Recent Research on Indium-Gallium-Nitride-Based Light-Emitting Diodes: Growth Conditions and External Quantum Efficiency

The optimization of the synthesis of III-V compounds is a crucial subject in enhancing the external quantum efficiency of blue LEDs, laser diodes, quantum-dot solar cells, and other devices. There are several challenges in growing high-quality InGaN materials, including the lattice mismatch between GaN and InGaN causing stress and piezoelectric polarization, the relatively high vapor pressure of InN compared to GaN, and the low level of incorporation of indium in InGaN materials. Furthermore, carrier delocalization, Shockley–Read–Hall recombination, auger recombination, and electron leakage in InGaN light-emitting diodes (LEDs) are the main contributors to efficiency droop. The synthesis of high-quality III-V compounds can be achieved by optimizing growth parameters such as temperature, V/III ratios, growth rate, and pressure. By reducing the ammonia flow from 200 sccm to 50 sccm, increasing the growth rate from 0.1 to 1 m/h, and lowering the growth pressure from 250 to 150 Torr, the external quantum efficiency of III-V compounds can be improved at growth temperatures ranging from 800 °C to 500 °C. It is crucial to optimize the growth conditions to achieve high-quality materials. In addition, novel approaches such as adopting a microrod crystal structure, utilizing the piezo-phototronic effect, and depositing AlN/Al2O3 on top of the P-GaN and the electron-blocking layer can also contribute to improving the external quantum efficiency. The deposition of a multifunctional ultrathin layers of AlN/Al2O3 on top of the P-GaN can enhance the peak external quantum efficiency of InGaN blue LEDs by 29%, while the piezo-phototronic effect induced by a tensile strain of 2.04% results in a 183% increase in the relative electroluminescence intensity of the LEDs. This paper also discusses conventional and inverted p-i-n junction structures of LEDs.

Ultrahigh density InGaN/GaN nanopyramid quantum dots for visible emissions with high quantum efficiency

In this study, the selective area epitaxy (SAE) of InGaN/GaN nanopyramid quantum dots (QDs) on a block copolymer patterned (BCP) GaN template using metalorganic chemical vapor deposition is reported. The pattern transfer process and SAE process are developed to enable a ultrahigh density of 7–9 × 1010 cm−2 QD formation with a feature size of 20–35 nm. The growth mechanism and geometrical properties of the QDs were investigated by scanning electron microscopy and cross-sectional transmission electron microscopy, showing the nanopyramid QD structure with InGaN grown on semipolar {101¯1} planes. The optical characteristics of the nanopyramid QDs were examined by microphotoluminescence measurements. We observed QD emission centered at 488 and 514 nm, depending on the growth temperature employed. These emissions were found to be longer wavelength than those from a planar quantum well structure. This can be attributed to the combined effects of higher indium incorporation along the semipolar plane and a larger InGaN thickness. Furthermore, we also found that the QD emission intensity increases as the number of InGaN layers increases without wavelength shift, indicating a constant growth rate and indium incorporation along the semipolar plane after the formation of the nanopyramid structure. The internal quantum efficiency is estimated to be over 60% by comparing the photoluminescence (PL) intensity of QDs at low temperature and room temperature. PL emission wavelength shows an 11 nm blue shift, while the full width at half maximum decreases from 68 (351 meV) to 56 nm (303 meV) from room temperature to low temperature. By employing BCP lithography and SAE technique, we successfully demonstrated that ultrahigh density, small size InGaN/GaN nanopyramid QDs with visible emission were achieved, which could be a potential active region for QD light-emitting diodes and/or lasers.

Fabrication of ZnSnO3@In2O3 core-shell based 1D microfiber heterostructure for high energy density asymmetric supercapacitors

Core-shell microfibers have witnessed a substantial demand surge in developing supercapacitors (SCs) owing to their enhanced conductivity, high surface area, and structural stability. Here, we report a facile low-cost electrospun ZnSnO3 @In2O3 core-shell microfibers heterostructure for SC application. The distinct fibrous morphology and synergistic incorporation of Zinc (Zn), Tin (Sn), and Indium (In) demonstrate significantly enhanced electrochemical performance while assembled in an asymmetric SC (ASC) by utilizing ZnSnO3 @In2O3 core-shell as positive and activated carbon (AC) as negative electrode. The ASC device exhibits an excellent specific capacitance of 160 F/g at 1 A/g along with a maximum specific energy of 40 Wh/kg. The ASC also records 86.95% capacitance retention with an exceptional 90% coulombic efficiency retention over 15,000 cycles at 15 A/g. This novel ZnSnO3 @In2O3 core-shell//AC signifies great potential in achieving high-performance electrochemical energy storage devices.

Incorporation of indium into GaN layers in the context of MOVPE thermodynamics and growth – Ab initio studies

Indium incorporation on the GaN surface (0001) has been analyzed in the context of InGaN growth by Metal Organic Vapor Phase Epitaxy (MOVPE). To understand phenomena at the atomic level, calculations based on Density Functional Theory (DFT) and thermodynamic analysis of the surface processes have been performed. The considerations are limited to the terrace on GaN (0001) surface, covered fully by NH3/NH2 species. The ab initio results indicate that the adsorption energy strongly depends on the electronic properties of the surface. The adsorption energy varies from EadsDFT=-10.0eV for fully NH2 covered to EadsDFT=-3.0eV for mixed 0.69 NH2 + 0.31 NH3 covered surface. This change is related to Fermi level position moved from within valence band, across the bandgap, up to within conduction band. The shift in Fermi energy impacts the energy gained during adsorption due to electron occupation of surface states. Furthermore, a comprehensive thermodynamic analysis was conducted, revealing an additional, albeit smaller, contribution from the vibrational degrees of freedom to free energy. The combined effect of these factors leads to an increase in the equilibrium pressures of indium related to the increase in hydrogen pressure, which correlates with high coverage by ammonia molecules. The results demonstrate that the significant reduction in indium incorporation into InGaN layers during MOVPE growth under conditions of low hydrogen concentration in the vapor can be attributed to the influence of hydrogen on In adsorption processes.

Wafer-scale emission uniformity of InGaN-based red light-emitting diodes on an in situ InGaN decomposition template

We propose a strain relaxed template (SRT), which consists of an InGaN decomposition layer (DL) and GaN protecting layers grown at three different temperatures as decomposition stop layers (DSLs), to enhance the indium incorporation in quantum wells. The high-temperature growth of the DSL decomposed the InGaN DL and created voids inside to release the strain of the as-grown templates. Although the surface morphology slightly degraded with the DL-DSL SRT, the emission wavelength over the 4-in. wafer was uniform with a standard deviation of 3.4 nm. In addition, the chip containing DL-DSL SRT exhibited an average redshift of 15 nm in peak wavelength compared to the chip without DL-DSL SRT, and the full widths at half-maximum of all samples were below 55 nm. Finally, we achieved an InGaN red LED chip using the DL-DSL SRT structure, exhibiting a red emission of 634 nm at 10 A/cm2 with an external quantum efficiency of 1.3%. The high-efficiency and uniform emission wavelength across the epi-wafer demonstrate the great potential of inserting a DL-DSL SRT to mass-produce high-performance, long-wavelength InGaN LEDs.

Enhancing Electrocatalytic Conversion of Bicarbonate to Formate by Via Bismuth Alloys

The bicarbonate reduction reaction has been emerging as a promising approach for converting CO2-riched medium to profitable products. However, the reduction of bicarbonate to formate still requires further development to achieve a moderate faradic efficiency. Herein, we introduced a low hydrogen-affinity metal (indium) into bismuth-based materials for BRR. It shows a favorable FEformate of 84.81%, a considerable formate partial current density of 241 mA∙cm-2, and a superior formate generation rate of 56 mmol∙L-1∙cm-2∙h-1.Comprehensive ex-situ XRD characterization suggests that the incorporation of indium will inhibit the phase transformation from metallic bismuth to a bismuth subcarbonate species, which leads to the enhanced performance for bicarbonate reduction to facilitate improved cathodic formate production from the In-Bi alloy as compared to pure Bi.

Biaxial, Hybrid Plastic-Elastic Relaxation in Micropatterned Semipolar InGaN Buffer Layers Improves Quality of Templated Quantum Well Emitters

Despite significant progress and multiple creative approaches taken toward the realization of long-wavelength III-nitride based light emitters over the past decade, high double-digit external quantum efficiencies remain elusive for GaN/InGaN based devices for wavelengths longer than 525 nm. This stems from the large mismatch between the GaN and InGaN lattice that manifests in deleterious crystal strain gradients, degrades surface growth morphology, and introduces diverse and potent nonradiative defects.A promising route to mitigation of strain-based effects is templating epitaxial growth on relaxed InGaN epilayers; in particular, a known and controllable platform for uniaxial strain relaxation is the creation of 1-D misfit dislocation arrays at semipolar GaN/InGaN heterointerfaces. Leveraging work by Hardy et al. on achieving >200 nm thick, partially relaxed semipolar InGaN layers [1] and precise determination of InGaN epilayer strain state and composition by Young et al. [2], we explore the potential for 2-D buffer layer relaxation in (11-22) InGaN layers via micron- and sub-micron patterning. Cathodoluminescence microscopy and x-ray diffraction indicated significant increases in biaxial epilayer relaxation with increased pillar aspect ratio; quantum wells deposited atop these relaxed InGaN buffers showed dramatic threading dislocation reduction, luminescence and morphology improvements, and evidence of improved indium incorporation relative to planar samples at nominally identical growth conditions.[1] Hardy, M.T., Young, E.C., Hsu, P.S., Haeger, D.A., Koslow, I.L., Nakamura, S., DenBaars, S.P., Speck, J.S. Suppression of m-plane and c-plane slip through Si and Mg doping in partially relaxed (20-21) InGaN/GaN heterostructures. Appl. Phys. Lett. 101, 132102 (2012).[2] Young, E. C., Romanov, A.E., Speck, J.S., Determination of composition and lattice relaxation in semipolar ternary (In,Al,Ga)N strained layers from symmetric x-ray diffraction measurements. Appl. Phys. Express. 4, 061001 (2011).

Pulse‐Modulation Controllable Monolithic Full‐Color Semipolar GaN‐based Light Emitting Diodes

AbstractMonolithic multi‐color light‐emitting diodes (LEDs) offer numerous advantages as multi‐functional lighting sources. However, the achievement of full‐color monolithic LEDs spanning from red to blue wavelengths is limited by the InN‐GaN material system. To overcome this limitation, this work demonstrates a new approach using hexagonal epitaxial lateral overgrowth to reduce the density of crystal defects and form micro‐surface structures. By utilizing arrowhead‐like surfaces in semipolar GaN films, indium incorporation can be controlled, leading to larger band‐filling effects and enabling full‐color red, green, and blue emissions from a single LED. Nonetheless, the red emission in monolithic full‐color LEDs is weaker than the blue emission due to the band‐filling induced blueshift that occurs with increasing current injection. To address this issue, pulse amplitude modulation and pulse width modulation modes are introduced to control the emission intensity from red to blue wavelengths. As a result, the study achieves a monolithic trichromatic white LED with color coordinates of (0.2985, 0.3948) and a color temperature of ≈6700 K by simultaneously emitting red, green, and blue LEDs with the same emission intensities. This achievement holds great promise for the development of high‐performance full‐color LEDs for multifunctional lighting sources that can span red, green, and blue wavelengths.

Surfactant behavior and limited incorporation of indium during in situ doping of GeSn grown by molecular beam epitaxy

Surfactant behavior and limited incorporation of indium during <i>in situ</i> doping of GeSn grown by molecular beam epitaxy

Correlation between the Surface Undulation and Luminescence Characteristics in Semi-Polar 112¯2 InGaN/GaN Multi-Quantum Wells

Surface undulation was formed while growing InGaN/GaN multi-quantum wells on a semi-polar m-plane (1–100) sapphire substrate. Two distinct facets, parallel to 112¯2 and 011¯1, were formed in the embedded multi-quantum wells (MQWs). The structural and luminescence characteristics of the two facets were investigated using transmission electron microscopy equipped with cathodoluminescence. Those well-defined quantum wells, parallel and slanted to the growth plane, showed distinct differences in indium incorporation from both the X-ray yield and the contrast difference in annular darkfield images. Quantitative measurements of concentration in 011¯1 MQWs show an approximately 4 at% higher indium incorporation compared to the corresponding 112¯2 when the MQWs were formed under the same growth condition.

Strain-Induced Band Gap Variation in InGaN/GaN Short Period Superlattices

The use of strained substrates may overcome indium incorporation limits without inducing plastic relaxation in InGaN quantum wells, and this is particularly important for short-period InGaN/GaN superlattices. By incorporating elastic strain into these heterostructures, their optoelectronic behavior is modified. Our study employed density functional theory calculations to investigate the variation in the band-gap energy of short-period InGaN/GaN superlattices that comprise pseudomorphic quantum wells with a thickness of just one monolayer. Heterostructures with equibiaxially strained GaN barriers were compared with respective ones with relaxed barriers. The findings reveal a reduction of the band gap for lower indium contents, which is attributed to the influence of the highly strained nitrogen sublattice. However, above mid-range indium compositions, the situation is reversed, and the band gap increases with the indium content. This phenomenon is attributed to the reduction of the compressive strain in the quantum wells caused by the tensile strain of the barriers. Our study also considered local indium clustering induced by phase separation as another possible modifier of the band gap. However, unlike the substrate-controlled strain, this was not found to exert a significant influence on the band gap. Overall, this study provides important insights into the behavior of the band-gap energy of strained superlattices toward optimizing the performance of optoelectronic devices based on InGaN/GaN heterostructures.

High‐Efficiency InGaN Red Mini‐LEDs on Sapphire Toward Full‐Color Nitride Displays: Effect of Strain Modulation

AbstractInGaN red light emitting diode (LED) is one of the crucial bottlenecks that must be broken through to realize high‐resolution full‐color mini/micro‐LED displays. The efficiency of InGaN LEDs drops rapidly as the emission spectra go from blue/green to red range due to the poor quality of high‐indium‐content InGaN materials. Here, high‐performance InGaN red LEDs on sapphire grown by metal–organic chemical vapor deposition through strain modulation are reported. A composite buffer layer is proposed to increase the surface lattice constant of GaN and hence successfully enhances the indium incorporation efficiency of the following InGaN active layers. Consequently, a high‐efficiency InGaN red mini‐LED chip (mesa area: 100 × 200 µm2) with a peak wavelength of 629 nm and an external quantum efficiency of 7.4% is realized. Finally, a full‐color nitride mini‐LED display panel with 74.1% coverage of Rec.2020 color gamut by using the InGaN red mini‐LED chips is fabricated. The study signifies the great potentials of full‐nitrides high‐resolution full‐color mini/micro‐LED displays.