A5102764843- Chalcogenide Semiconductor Thin Films
- Quantum Dots Synthesis And Properties
- Copper-based nanomaterials and applications
- Semiconductor materials and devices
- Semiconductor materials and interfaces
- Thin-Film Transistor Technologies
- ZnO doping and properties
- Silicon Nanostructures and Photoluminescence
- Nanowire Synthesis and Applications
- Liquid Crystal Research Advancements
- Perovskite Materials and Applications
- Advancements in Semiconductor Devices and Circuit Design
- Electrical and Thermal Properties of Materials
- Silicon and Solar Cell Technologies
- Photonic Crystals and Applications
- Semiconductor Lasers and Optical Devices
- Transition Metal Oxide Nanomaterials
- Advanced Memory and Neural Computing
- Photochromic and Fluorescence Chemistry
- Gas Sensing Nanomaterials and Sensors
- Ion-surface interactions and analysis
- Advanced Materials and Mechanics
- Integrated Circuits and Semiconductor Failure Analysis
- Ferroelectric and Negative Capacitance Devices
- Ga2O3 and related materials
Daegu Gyeongbuk Institute of Science and Technology
2016-2025
Government of the Republic of Korea
2019
Daegu University
2014
University of Seoul
2007-2011
Daegu TechnoPark
2010-2011
Using an appropriate SeS<sub>2</sub>/Se weight ratio, band gap grading was realized. By increasing the value of<italic>V</italic><sub>OC</sub>through in depletion region, a record<italic>V</italic><sub>OC</sub>deficit of 0.576 V and efficiency 12.3% were obtained.
We fabricated CZTSSe thin films using optimized SLG-Mo/Zn/Cu/Sn (MZCT) as a stacked structure and described the phenomenon of Zn elemental volatilization MZCT structure.
Abstract For kesterite copper zinc tin sulfide/selenide (CZTSSe) solar cells to enter the market, in addition efficiency improvements, technological capability produce flexible and large-area modules with homogeneous properties is necessary. Here, we report a greater than 10% for cell area of approximately 0.5 cm 2 8% larger certified CZTSSe cells. By designing thin multi-layered precursor structure, formation defects defect clusters, particularly tin-related donor defects, controlled, open...
Abstract Cu 2 ZnSnS 4 (CZTS)‐based materials have a useful band gap and high absorption coefficient; however, their power conversion efficiency is low compared with that of CdTe Cu(In,Ga)Se ‐based solar cells. Two the factors strongly affect CZTS cell characteristics are MoS layer presence defects. In this study, Mo back‐contact layers were annealed to control formation Na content in before absorber precursor was deposited. The increase oxygen suppressed formation. addition, diffusion during...
The improvement of the efficiency Cu2ZnSn(S,Se)4 (CZTSSe)-based solar cells requires formation high-grain-sized pure CZTSSe throughout film. We have successfully selenized precursor samples Cu/SnS/ZnS/Mo/Soda lime glass in an almost sealed selenium furnace. Owing to presence confined and high-pressure Se vapor furnace, easily diffused into samples, high-quality Se-rich absorbers were obtained. To understand effect growth mechanism our annealing system, this study examines phase evolution...
Abstract Although Cu 2 ZnSnS 4 (CZTS) has attracted attention as an alternative absorber material to replace CuInGaSe (CIGS) in solar cells, the current level of understanding its characteristic loss mechanisms is not sufficient for achieving high power conversion efficiency. In this study, which aimed minimize losses across devices, we examined relations between compositional ratio distribution layer, subsequent defect formation, and surface electrical characteristics. A high‐temperature...
Abstract Improving the efficiency of kesterite (Cu 2 ZnSn(S,Se) 4 ; CZTSSe) solar cells requires understanding effects Na doping. This paper investigates these by applying a NaF layer at various positions within precursors. The position is important because produces Na‐related defects in absorber and suppresses formation intrinsic defects. By investigating precursors with positions, sulfo‐selenization mechanism characteristics defect are confirmed. Applying onto Zn CZTSSe precursor limits...
Effective adding/removal of organic chemicals to/from CZTS precursor thin films for preparing uniform with optimal photovoltaic properties was achieved by pre-annealing precursors containing thiourea.
Abstract Herein, a liquid‐assisted grain growth (LGG) mechanism for vacuum‐processed Cu 2 ZnSn(S 1− x Se ) 4 (CZTSSe) absorber that is enabled by the presence of liquid phase containing predominantly Cu, Sn, and (L‐CTSe) suggested to explain large size up ≈6 µm obtained at low temperatures, such as 480 °C. In this system, LGG plays key role in achieving CZTSSe absorber, but residual L‐CTSe, factor LGG, deteriorates device performance. L‐CTSe residue can possibly remain when using metal...
Stainless steel (SS) foil is made of abundant materials and a durable flexible substrate, but the efficiency solar cell on SS deteriorates<italic>via</italic>the diffusion impurities from substrate into Cu<sub>2</sub>ZnSn(S,Se)<sub>4</sub>(CZTSSe) absorber layer.
Abstract Bifacial CuInSe₂ (CISe) solar cells hold significant promise for various applications but are constrained by relatively low power conversion efficiencies. This study boosts performance through reducing CISe absorber deposition temperature and using low‐Ga back grading an optimum gallium‐to‐indium ratio (Ga/(Ga+In); GGI) profile. Low temperatures reduced ITO contact thermal degradation, while Ga concentration GaO X formation CISe/ITO charge recombination. Ag incorporation...
In this study, we analyzed the effect of position Ag in stacked precursor structure CZTSSe solar cells. Five structures were designed by adding a 5-nm-thick...
Recently, highly efficient CZTS solar cells using pure metal precursors have been reported, and our group created a cell with 12.6% efficiency, which is equivalent to the long-lasting world record of IBM. In this study, we report new secondary phase formation mechanism in back contact interface. Previously, CZTSSe decomposition Mo has proposed explain void Mo-back region. sulfo-selenization system, voids phases well explained by unique wetting properties liquid above peritectic reaction...
Abstract CZTSSe thin‐film absorbers were grown by stacked ZnS/SnS/Cu sputtering with compound targets, and the precursors annealed in a furnace Se atmosphere. We controlled thickness of ZnS precursor layer for thin films order to reduce secondary phases improve performance devices. The optimal value was determined absorbers, this configuration showed an efficiency up 9.1%. In study, we investigated depth profiles samples determine presence Raman spectroscopy Kelvin probe force microscopy. Cu...
Abstract Understanding the defect characteristics that occur near space‐charge regions (SCRs) of kesterite (CZTSSe) solar cells is important because recombination loss at CZTSSe/CdS interface considered main cause their low efficiency. CZTSSe surfaces with different elemental compositions were formed without polishing (C00) and for 20 s (C20) 60 (C60). For C60, a specific region SCR was excessively Cu‐rich Zn‐poor compared to C00 C20. Various charged defects where variation large. As deep...
Abstract Cu 2 ZnSn(S,Se) 4 (CZTSSe) solar cells have resource distribution and economic advantages. The main cause of their low efficiency is carrier loss resulting from recombination photo‐generated electron hole. To overcome this, it important to understand electron‐hole behavior characteristics. determine the separation characteristics, we measured surface potential local current in terms absorber depth. elemental variation intragrains (IGs) at grain boundaries (GBs) caused a band edge...
This is the Cu 2 ZnSnS 4 (CZTS) films were fabricated on glass substrates by sputtering using compound material targets. The fabrication method combines deposition of metallic precursors and sulfurization annealing process S vapor. optimal precursor sequence for CZTS growth was Cu/SnS/ZnS/Mo. To optimize composition thickness CZTS, layer varied. best cell had an area 0.185 cm , Cu/(Zn + Sn) = 0.89, Zn/Sn 1.04, S/(metal) 1.13 showed open‐circuit voltage ( V OC ) 0.66 V, a short‐circuit...
CZTSSe thin films with various S/(S + Se) compositions were synthesized by adding SeS<sub>2</sub> powder in an optimized selenization process.