Enhanced Device Performance Research Articles

Large Deflection and Post-Buckling Analysis of Cantilever Nanorods Including Effects of Couple and Surface Stresses by Intrinsic Coordinate Finite Elements

This paper presents a novel approach to the analysis of large deflection and post-buckling behavior of cantilever nanorods under different load conditions. The proposed approach utilizes a variational method, incorporating the Gurtin–Murdoch surface elasticity theory and the consistent couple stress theory to account for size-dependency effects. By accounting for the strain energy contributions of the bulk material, surface layer, and load conditions, this approach expresses the behavior of the nanorods in terms of their intrinsic coordinates. A finite element method was used to solve this numerical problem, generating a system of non-linear equations that were iteratively solved using the Newton–Raphson method. The results obtained from the finite element method were confirmed by those from the shooting method. Also, it highlights the effectiveness of the variational model in predicting the large deflection and post-buckling behavior of cantilever nanorods while considering both surface stress and couple stress effects. Furthermore, the study investigated the influence of surface stress and couple stress on the response of the nanorods to point and uniform loads. The results showed that incorporating both effects enhanced the stiffness of the nanorods compared to scenarios in which these effects were neglected. In addition, the couple stress effect was found to have a greater influence on the stiffening of nanorods for the same value of unitless parameters compared to surface stress effects. These findings offer valuable insights into the large deflection and post-buckling behavior of cantilever nanorods and highlight the importance of surface stress and couple stress effects. The model proposed in this study has potential applications in advanced technological device designs by providing a comprehensive understanding of the mechanical response of nanorods, allowing for more accurate predictions and enhanced device performance.

Enhancing microstructure and device performance of InGaN quantum dot micro-LEDs through substrate off-cut angle modulation

InGaN quantum dots (QDs) are regarded as a compelling candidate material for the fabrication of high-quality GaN-based micro-LEDs. In this work, to study the impact of a substrate structure on InGaN QDs and QD-based micro-LEDs, GaN-on-sapphire substrates with off-cut angles toward the a-axis of 0.2°, 0.4°, and 0.7° were utilized as templates for the fabrication of InGaN QDs and InGaN QDs-based micro-LEDs. Experimental results show that GaN template with 0.4° off-cut angle exhibits the narrowest terrace width and enables InGaN QDs to be higher and more uniform. The InGaN QD sample grown on 0.4° substrate has a very small wavelength shift of 2.5 nm with temperature increasing and owns the longest photoluminescence peak wavelength implying the highest In content. Furthermore, electroluminescence (EL) spectra demonstrate that QD-based micro-LED array has excellent wavelength stability under various injection currents, and the stability can be improved further on a GaN template with narrower terraces. The results indicate that altering the terrace width of GaN template is a feasible scheme for improving the properties of GaN-based micro-LEDs.

Understanding the Heterointerfaces in Perovskite Solar Cells via Hole Selective Layer Surface Functionalization.

Interfaces in perovskite solar cells (PSCs) play a pivotal role in determining device performance by influencing charge transport and recombination. Understanding the physical processes at these interfaces is essential for achieving high-power conversion efficiency in PSCs. Particularly, the interfaces involving oxide-based transport layers are susceptible to defects like dangling bonds, excess oxygen, or oxygen deficiency. To address this issue, the surface of NiOx is passivated using octadecylphosphonic acid (ODPA), resulting in improved charge transport across the perovskite hole transport layer (HTL) interface. This surface treatment has led to the development of hysteresis-free devices with an impressive ≈13% increase in power conversion efficiency. Computational studies have explored the halide perovskite architecture of ODPA-treated HTL/Perovskite, aiming to unlock superior photovoltaic performance. The ODPA surface functionalization has demonstrated enhanced device performance, characterized by superior charge exchange capacity. Moreover, higher band-to-band recombination in photoluminescence and electroluminescence indicates presence of lower mid-gap energy states, thereby increasing the effective photogenerated carrier density. These findings are expected to promote the utilization of various phosphonic acid-based self-assembly monolayers for surface passivation of oxide-based transport layers in perovskite solar cells. Ultimately, this research contributes to the realization of efficient halide PSCs by harnessing the favorable architecture of NiOx interfaces.

High-Quality Hybrid Perovskite Thin Films by Post-Treatment Technologies in Photovoltaic Applications.

Incredible progress in photovoltaic devices based on hybrid perovskite materials has been made in the past few decades, and a record-certified power conversion efficiency (PCE) of over 26% has been achieved in single-junction perovskite solar cells (PSCs). In the fabrication of high-efficiency PSCs, the postprocessing procedures toward perovskites are essential for designing high-quality perovskite thin films; developing efficient and reliable post-treatment techniques is very important to promote the progress of PSCs. Here, recent post-treatment technological reforms toward perovskite thin films are summarized, and the principal functions of the post-treatment strategies on the design of high-quality perovskite films have been thoroughly analyzed by dividing into two categories in this review: thermal annealing (TA)-related technique and TA-free technique. The latest research progress of the above two types of post-treatment techniques is summarized and discussed, focusing on the optimization of postprocessing conditions, the regulation of perovskite qualities, and the enhancement of device performance. Finally, an outlook of the prospect trends and future challenges for the fabrication of the perovskite layer and the production of highly efficient PSCs is given.

Significant dark current suppression in perovskite photodetectors using hole transport materials of lithium-doped vanadium oxide

Suppressing dark current density (Jdark) is one of most important strategies for improving responsivity (R), detectivity (D*), and linear dynamic rang (LDR) of perovskite photodetectors (PDs). However, the modulation mechanism of intrinsic and interfacial features of hole transport materials (HTMs) on their photodetection performance remains unclear and is related to complicated factors, resulting in perovskite PDs to generally suffer from high Jdark. In this study, we systematically investigated the effect of Li-doped VOX on the photodetection performance of perovskite PDs. The Li-doped VOX HTMs showed superior conductivity, high transmittance, and enlarged interfacial adhesion between the HTMs and perovskite layer. The PDs based on Li-doped VOX HTMs exhibited at least two orders lower Jdark and almost 1.6 times greater photocurrent densities (Jph) compared with those based on pristine VOX HTMs, while significantly maintained high external quantum efficiency (∼84 %) and impressive Dmax* of 1.23 × 1013 Jones. The enlarged surface roughness of Li-doped VOX HTMs leads to the enhancement of the interfacial adhesion between the HTMs and perovskite layer, which decreases the defects density of perovskite layer and trap-assisted recombination inside PDs, thus resulting in the significant suppression of Jdark and the improved collection of photoinduced charges. Overall, our findings provide a facial way to suppress Jdark for enhancing device performance of PDs.

Electrical performance estimation and comparative study of heterojunction strained and conventional gate all around nanosheet field effect transistors

Abstract In this paper, we propose a novel type of Gate All Around Nanosheet Field Effect Transistor (GAA NS FET) that incorporates source heterojunctions and strained channels and substrate. We compare its electrical characteristics with those of the Heterojunction Gate All Around Nanosheet Field Effect Transistor (Heterojunction GAA NS FET) and the Conventional Gate All Around Nanosheet Field Effect Transistor (Conventional GAA NS FET). We investigate the impact of electrostatic control on both DC and analog parameters such as gate capacitance (C gg), transconductance g m, and cut-off frequency (f T) for all three device types. In our Proposed GAA NS FET, we employ Germanium for the source and substrate regions, Silicon/Germanium/Silicon (Si/Ge/Si) for the channel, and Silicon for the drain region. The introduction of strain into the nanosheet and the use of a heterojunction structure significantly enhance device performance. Before utilizing a model to analyze a semiconductor device, it is crucial to accurately determine and elaborate on the model parameters. In this case, we solve the Density Gradient (DG) equation self-consistently to obtain the electrostatic potential for a given electron Fermi-level distribution, use the Shockley-Read-Hall (SRH) equation to estimate carrier generation, account for bandgap narrowing in transport behavior, and consider auger recombination. Our general results indicate a notable improvement in drain current, transconductance, and unity-gain frequency by approximately 42%, 53%, and 31%, respectively. This enhancement results in superior RF performance for the Proposed GAA NS FET compared to both the heterojunction GAA NS FET and the conventional GAA NS FET.

Reduction of phosphorus diffusion in bulk germanium via argon/phosphorus co-implantation and RTA annealing

Germanium has received increased research interest for use in next-generation CMOS technology as its high carrier mobilities allow for enhanced device performance without further device scaling. Fabrication of high-performance NMOS Ge devices is hindered by high diffusivity and low activation of n-type implanted dopants. While the high solid solubility of P in Ge makes it an ideal dopant, its diffusion mechanism is poorly understood and results in heavy tradeoffs between implanted dopant diffusion and electrical activation. In this study, we demonstrate the suppression of in-diffusion of implanted P via a co-implantation with Ar. Diffusivity of implanted P species and their activation is investigated over a wide range of annealing temperatures and times. P diffusion was explored by secondary-ion-mass-spectrometry and the diffusivity of P was extracted by solving the 2D diffusion equation using the Crank–Nicolson method, and the dopant electrical activation was extracted from the Hall effect measurements. The co-implantation of P with Ar entirely suppresses P in-diffusion up to annealing temperatures as high as 700 °C but at the cost of its reduced electrical activation. Extracted diffusivity reveals a highly correlated exponential relationship with annealing. P activation energy was extracted from Arrhenius behavior. A 450 °C/10 min annealing of P implant shows negligible in-diffusion of P with the activation as high as 70%. RTA processing of the Ar/P co-implanted sample at 750 °C for 1 min results in a negligible P in-diffusion and an electrical activation of 20%.

Recent Progress of Vertical Graphene: Preparation, Structure Engineering, and Emerging Energy Applications.

Vertical graphene (VG) nanosheets have garnered significant attention in the field of electrochemical energy applications, such as supercapacitors, electro-catalysis, and metal-ion batteries. The distinctive structures of VG, including vertically oriented morphology, exposed, and extended edges, and separated few-layer graphene nanosheets, have endowed VG with superior electrode reaction kinetics and mass/electron transportation compared to other graphene-based nanostructures. Therefore, gaining insight into the structure-activity relationship of VG and VG-based materials is crucial for enhancing device performance and expanding their applications in the energy field. In this review, the authors first summarize the fabrication methods of VG structures, including solution-based, and vacuum-based techniques. The study then focuses on structural modulations through plasma-enhanced chemical vapor deposition (PECVD) to tailor defects and morphology, aiming to obtain desirable architectures. Additionally, a comprehensive overview of the applications of VG and VG-based hybrids d in the energy field is provided, considering the arrangement and optimization of their structures. Finally, the challenges and future prospects of VG-based energy-related applications are discussed.

A breakthrough for temperature and linearity stability from device to circuit-level with 14 nm junctionless SOI FinFET: Advancing K-band LNA performance

SOI junctionless (JL) FinFETs are well-suited for future wireless communication systems; however, they suffer from the self-heating effect (SHE), which diminishes performance at higher temperatures. We proposed a novel structure called p-layer JL-FinFET (pL-JL-FinFET) to improve high-frequency performance at high temperatures. The Ge p-layer beneath the Silicon Fin increases electron current density and enhances device performance. Two high thermal conductivity 4H-SiC boxes are placed below the source and drain regions to overcome SHE. The pL-JL-FinFET exhibits the maximum transconductance of 148 μS, unity gain cut-off frequency of 455 GHz, and maximum available gain of 28.6 dB, which are improved by 208 %, 26 %, and 35 %, respectively, compared to regular JL-FinFET. Temperature analysis demonstrates suppressed SHE and better thermal stability than the regular JL-FinFET. Also, the pL-JL-FinFET shows superior thermal behavior in different fin shapes. The pL-JL-FinFET with a rectangular fin shape shows excellent linearity and high-frequency performance, achieving unconditional stability and minimum noise figure (NFmin) of less than 1 dB. An extracted small signal model is used to design a K-band low noise amplifier (LNA) with maximum NF and gain values of 0.75 dB and 18.7 dB. The pL-JL-FinFET opens opportunities for reliable, high-performance RF circuits while effectively managing thermal behavior.

Dielectric, reflection loss and physicochemical studies of Cr doped Ba–Sr based W type hexagonal ferrites for microwave absorption applications

The utilization of hexagonal structures in nano ferrites has been employed for absorption because of their dielectric, attenuation characteristics, and reflection losses. Electromagnetic pollution is one of the significant issues in cleaning the environment. Electronic devices produce pollution and are hazardous to human health. Therefore, ferrite materials have been used for absorption purposes. In this study, the impact of chromium substitution on the structural and dielectric specifications of the Barium-strontium-based W-type hexagonal ferrites has been investigated and used for microwave absorption application. The sol-gel auto-ignition process prepared w-type hexagonal ferrites with Ba0.5Sr0.5Mg2CrxFe16-xO27 (x = 0.0, 0.1, 0.2, 0.3, and 0.4). According to XRD examination, the formation of single-phase W-type hexagonal ferrites was proven. The synthesized composition is confirmed to be nanocrystalline because the calculated crystallite size value is in the nanometer range. FTIR analysis confirmed the structure of W-type hexagonal ferrite. Raman spectroscopic study examined the vibrational and rotational modes of molecules. Survey spectra of XPS, which include Ba, Sr, Mg, Fe, Cr, and O, confirmed the presence of all constituent elements. SEM analysis confirmed that the sample contains grains with a hexagonal platelet shape. The results showed that increasing chromium concentration reduced the dielectric permittivity, tan loss, and ac conductivity. At x = 0.4, the reflection loss value is very low. The recorded value is −79.62 dB, corresponding to a frequency of 5.92 GHz, with a thickness of 1.75 mm. Because of this, W-type hexagonal ferrites are suitable for a wide range of electronic applications, including microwave absorbers, high-density recording media, and multilayer chip inductors. These applications have made it possible to functionalize these materials in order to enhance device performance and lower the size, weight, and cost of devices while also fostering the development of new technologies that have significantly improved the quality of our daily lives.

Defects go green: using defects in nanomaterials for renewable energy and environmental sustainability

Induction of point defects in nanomaterials can bestow upon them entirely new physics or augment their pre-existing physical properties, thereby expanding their potential use in green energy technology. Predicting structure-property relationships for defects a priori is challenging, and developing methods for precise control of defect type, density, or structural distribution during synthesis is an even more formidable task. Hence, tuning the defect structure to tailor nanomaterials for enhanced device performance remains an underutilized tool in materials design. We review here the state of nanomaterial design through the lens of computational prediction of defect properties for green energy technology, and synthesis methods to control defect formation for optimal performance. We illustrate the efficacy of defect-focused approaches for refining nanomaterial physics by describing several specific applications where these techniques hold potential. Most notably, we focus on quantum dots for reabsorption-free solar windows and net-zero emission buildings, oxide cathodes for high energy density lithium-ion batteries and electric vehicles, and transition metal dichalcogenides for electrocatalytic green hydrogen production and carbon-free fuels.

Interfacial Modulation through Mixed‐Dimensional Heterostructures for Efficient and Hole Conductor‐Free Perovskite Solar Cells

AbstractPerovskite solar cells have led the new surge of solar energy research. However, their instability is a pressing issue mostly attributed to the perovskite interface with charge‐selective transport layers. In this work, diethylammonium iodide (DEAI) surface treatment is used to mitigate interfacial non‐radiative recombination losses by forming a mixed phase of layered perovskite on the surface. This results in enhanced device performance with the power conversion efficiency of 23.3% and improved operational stability under thermal stress. Moreover, the DEAI treatment facilitates interfacial hole transfer, enabling a carbon‐based hole transport layer‐free perovskite solar cell with a power conversion efficiency of 15.6%.

High-Pressure Fabrication of Binary Organic Solar Cells with High Molecular Weight D18 Yields Record 19.65 % Efficiency.

In this work, inspired by the principles of a pressure cooker, we utilized a high-pressure method to address the processing challenges associated with high molecular weight polymers. Through this approach, we successfully dissolved high molecular weight D18 in chloroform at 100 °C within a pressure-tight vial. The increased steam pressure raised the boiling point and dissolving capacity of chloroform, enabling the creation of a hybrid film with superior properties, including more ordered molecular arrangement, increased crystallinity, extended exciton diffusion length, and improved phase morphology. Organic solar cells (OSCs) based on D18 : L8-BO prepared using this high-pressure method achieved an outstanding power conversion efficiency of 19.65 %, setting a new record for binary devices to date. Furthermore, this high-pressure method was successfully applied to fabricate OSCs based on other common systems, leading to significant enhancements in device performance. In summary, this research introduces a universal method for processing high molecular weight D18 materials, ultimately resulting in the highest performance reported for binary organic solar cells.

High‐Pressure Fabrication of Binary Organic Solar Cells with High Molecular Weight D18 Yields Record 19.65 % Efficiency

AbstractIn this work, inspired by the principles of a pressure cooker, we utilized a high‐pressure method to address the processing challenges associated with high molecular weight polymers. Through this approach, we successfully dissolved high molecular weight D18 in chloroform at 100 °C within a pressure‐tight vial. The increased steam pressure raised the boiling point and dissolving capacity of chloroform, enabling the creation of a hybrid film with superior properties, including more ordered molecular arrangement, increased crystallinity, extended exciton diffusion length, and improved phase morphology. Organic solar cells (OSCs) based on D18 : L8‐BO prepared using this high‐pressure method achieved an outstanding power conversion efficiency of 19.65 %, setting a new record for binary devices to date. Furthermore, this high‐pressure method was successfully applied to fabricate OSCs based on other common systems, leading to significant enhancements in device performance. In summary, this research introduces a universal method for processing high molecular weight D18 materials, ultimately resulting in the highest performance reported for binary organic solar cells.

Nanostructured FTO/Zr-hematite interfaces for solar water-splitting applications

Production of green hydrogen via photoelectrochemical (PEC) processes is strategic to store and distribute solar-harvested energy. Hematite (α-Fe2O3) is a promising photoactive photoanode material candidate for PEC applications, but its synthesis as a photoanode thin film needs improvements to optimize the PEC device's performance. We have previously explored a new strategy consisting of the use of Zr4+ as a surfactant (Zr-hematite) and Ni2+ as a co-catalyst element in the synthesis of hematite photoanode thin films deposited onto a fluorine-doped tin oxide (FTO) on a glass substrate, obtaining a significant enhancement of device performance. In this work, we demonstrated how the interface and surface conditions are affected by the incorporation of Zr4+ and Ni2+. Chemical mapping performed during scanning transmission electron microscopy (STEM) analysis indicated that Zr4+ preferentially segregated at the FTO/Zr-hematite interface and grain boundaries, while Ni2+ was only present on hematite-free surfaces. The Zr4+ between the hematite and substrate interface was associated with improved back contact, facilitating electron collection and favoring electron flow through the external circuit. Structural analysis of this interface region revealed lattice distortions and strain field accumulation at the FTO/Zr-hematite interface, which differed from the expected crystal structures of the database. Additionally, local FTO/Zr-hematite energy maps showed a 2.5-nm thick interface area containing a solid mixture of SnFeOx. Moreover, a change in the electronic state of Sn and Fe on the surface of the FTO substrate and Zr-hematite grains caused by the loss of oxygen atoms was observed. NiFeOx chemical bonding was observed with Ni addition by photoelectrodeposition on the Zr-hematite-free surface. This strong interaction explains the long-term stability test without traces of photocorrosion (ion release into the solution), as demonstrated in a previous paper. These findings introduce a novel perspective for developing strategies that enable synergistic photoanode modifications toward efficient solar-to-energy conversion.

Refractive Index Engineering as a New Degree of Freedom for Designing High‐Performance AlGaN‐Based Ultraviolet C Light‐Emitting Diodes

This study delves into a profound exploration, using simple yet effective Monte Carlo ray‐tracing simulations, of the influence of the refractive indices of multiple quantum wells (MQWs) and p‐type electron blocking layer (p‐EBL) on the photon propagation and subsequent light extraction behavior in AlGaN‐based ultraviolet‐C (UVC) light‐emitting diodes (LEDs), covering both transverse‐electric (TE) and transverse‐magnetic (TM) polarized light. Remarkably, the refractive index contrasts at the heterointerfaces of p‐EBL/MQWs/n‐AlGaN have a relatively minor impact on the extraction efficiency of TE‐polarized light but exert a significant influence on TM‐polarized light. This discrepancy arises from the substantial effect of total internal reflection at these heterointerfaces on the propagation of photons emitted at large angles. Thus, this observation elucidates the oversight of photon propagation in the conventional design of MQWs and p‐EBL in AlGaN‐based UVA and UVB LEDs, where TE‐polarized emission predominates. Building upon simulation results, a highly effective strategy for extracting TM‐polarized light in AlGaN‐based UVC LEDs is further demonstrated by combining refractive index engineering with inclined sidewalls. The findings suggest refractive index engineering can serve as a novel design parameter for AlGaN‐based UVC LEDs dominated by TM‐polarized emission, expanding the range of techniques available for enhancing device performance.

Back-surface electric field passivation of CdTe solar cells using sputter-deposited CdSe

CdTe back-surface passivation is one of the effective ways to enhance device performance. In recent years, the role of Se passivation in high performance CdSeTe thin film solar cell device has received increasing attention. However, current high-efficiency devices only have a considerable concentration of Se at the very front of the device, while most of the area on the back side of the absorber layer is not passivated by Se. This means that further efficiency improvements may be possible if more defects on the back surface of the absorber layer are passivated by Se, while maintaining the built-in field. Here, based on the magnetron sputtering process, chemical passivation and electric field passivation can be achieved when a small amount of CdSe is deposited on the CdTe back surface. When the CdSe thickness is ∼20 nm (Before annealing), the optimal cell current was increased from 23.8 mA/cm2 to 26 mA/cm2 and the efficiency was increased from 13.1% to 15.5%. External quantum efficiency and impedance spectroscopy measurements indicate that the performance improvement is due to the reduction of the interfacial recombination current on the back surface.

Tunable plasmon refractive index sensor and a slow-light device optimized by an improved genetic algorithm based on a MIM waveguide

A structure is proposed in this article consisting of a stub metal–insulator–metal (MIM) waveguide coupled with an embedded T-shaped square ring resonator (ETSRR). The transmission characteristics and magnetic field distribution of the design are analyzed in detail using the finite element method (FEM). Furthermore, the geometric parameters are optimized using an improved genetic algorithm to enhance device performance. The proposed structure is therefore an ideal candidate for realizing a refractive index sensor and slow-light device, with potential applications in various fields such as sensing and communication. Moreover, our study provides valuable insights to the design of surface plasmon polarition (SPP) waveguides with computer assistance.

Enhanced marine predators algorithm optimized support vector machine for IGBT switching power loss estimation

As the use of renewable energy generation continues to grow, improving power conversion efficiency has become an urgent task. This study aims to propose a high-precision power module loss estimation method, with a focus on predicting the switching losses of insulated gate bipolar transistor (IGBT) modules, which is crucial for the reliability assessment of IGBT modules. The main objective of this study is to establish a high-precision predictive model for IGBT module switching losses to enhance the reliability and efficiency of these devices. Firstly, a dynamic characteristic test platform was established to acquire relevant data for in-depth analysis of IGBT behavior. Secondly, given the excellent performance of support vector machine (SVM) in handling both strong and small-sized datasets, SVM was chosen as the foundational model for high-precision switching loss estimation. Subsequently, an enhanced marine predatory algorithm (EMPA), known for its superior convergence precision and speed, was introduced to optimize the random parameters of SVM. Finally, a method based on the optimized EMPA-SVM was constructed for predicting IGBT switching power losses. The proposed approach was validated using dynamic characteristic test data. And it indicated that the predictive model achieved the value of R 2 exceeding 99.8% for switching losses. Additionally, the mean absolute error and root mean square error metrics of EMPA-SVM model outperformed other models. Therefore, the research results unambiguously demonstrate the significant benefits of accurately predicting IGBT switching losses in enhancing device performance.

A Comprehensive Review on the Recent Strategy of Cation Substitution in CZTS(Se) Thin Films to Achieve Highly Efficient Kesterite Solar Cells

Kesterite Cu2ZnSnS4 (CZTS) and selenized CZTS (CZTSSe) are the most potential replacements of Cu(InxGa1−x)Se2 as absorber layers in thin‐film solar cells, aligning with modern green energy policies. In spite of a reported power conversion efficiency (η) of nearly 14.9%, their efficiency still lags much behind their predecessors like cadmium telluride and CIGS. Major obstacles hindering the performance of CZTS‐based thin‐film solar cells pertain to the formation of CuZn and ZnCu antisite defects, along with high density of 2CuZn + SnZn donor defects, which adversely affects open‐circuit voltage and η. To combat these challenges, researchers have explored cation substitution by incorporating alternative isovalent atoms, such as substituting Ag/Li for Cu, Mn/Cd for Zn, and Ge/Ti for Sn, as a potent strategy to inhibit severe potential fluctuations and undesirable tail states caused by Cu–Zn disorder and Sn‐related defects. Recently single‐cation substitution in CZTS (or CZTSSe) has garnered considerable attention, while dual‐cation incorporation has emerged as an intriguing avenue to enhance device performance, although in its nascent stage of research and development. This review discusses recent progress on cation substitution to suppress antisite defects in CZTS (or CZTSSe), leading to high‐efficiency thin‐film solar cells.