Improvement Of Crystal Quality Research Articles

Effects of off-axis angles of 4H-SiC substrates on properties of β-Ga2O3 films grown by low-pressure chemical vapor deposition

In this work, β-Ga2O3 films with (−201) preferred orientation were heteroepitaxially grown on SiC substrates with off-axis angles of 0°, 4° and 8° by low-pressure chemical vapor deposition (LPCVD). It is found that the crystal quality, surface morphology, electrical properties of the β-Ga2O3 films of the film are significantly sensitive to the off-axis angle of SiC substrates. The crystal quality and surface morphology of the film were significantly improved when the 4° off-axis substrate was used, of which the FWHM (Full width at half maximum) was as low as 0.169° and the Ra (Roughness Average) of the smooth surface was 1.98 nm. Due to the improvement of crystal quality, the Hall mobility of the films deposited on 4° off-axis substrates was increased to 50.88 cm2/V·s. The photoluminescence peak intensity of the film increases first and then decreases with the increase of the off-axis angle of the substrate. However, the use of the off-axis substrate has no obvious effect on the oxygen vacancy ratio of the films. The results of this study demonstrate the significance for the preparation of high quality heteroepitaxial β-Ga2O3 films on SiC substrate for the promising applications in power electronic and optoelectronic devices.

High-performance PbS detectors sensitized from one-step sensitization

Two-step sensitization is the key technique for achieving high-performance uncooled lead-salt infrared photoconductive detectors fabricated from vapor physic deposition (VPD) method. However, the commercialization of these devices is inhibited by the intricate sensitization processes, especially the iodination step, which requires precise control over high concentrations of iodine vapor. Herein, a one-step sensitization technique was proposed to improve the reliability of lead sulfide (PbS) detectors manufactured from VPD method. Moreover, the dependence of the detectivity on sensitization parameters involving the oxygen concentration, time, and temperature, was established and interpreted based on extensive studies on the sensitization of lead salt devices. The feasibility of the simplified sensitization was demonstrated by a room-temperature peak detectivity of 2.47 × 1010 cm Hz1/2 W−1 at 2.7 μm attained at 430 °C for 10 min in 50 % oxygen ambient. The evolution of phase, microstructure and electrical properties confirms the enhanced performance results from the improvement in PbS crystal quality as well as the formation of Pb3O2I2 and Pb2(SO4)O from high-temperature recrystallization. Therefore, the one-step sensitization paves a way for accelerating commercialization of lead-salt detectors fabricated by VPD technique.

Introduction of Co atoms into CdS thin films for improving photovoltaic properties

This paper represents a systematic work on the fabrication of chemical bath-grown CdS films with and without Co atoms and their photovoltaic performances in hybrid solar cells. Structural properties showed 1% Co-doping promoted crystal quality of CdS films. However, a poor crystal quality was developed above 3% Co concentrations. A reduction in sphere size of CdS samples was observed for 1% Co-doping which was ascribed to slow growth of film. Optical examination demonstrated CdS films with 1% Co-doping displayed the highest transparency of 85% in the visible and near-infrared regions, which were explained by the improvement of crystal quality. A maximum band gap of 2.43 eV was found for 1% Co-doped CdS films, whereas an increase in Co concentration to 7% led to a decline in the band gap of CdS that was attributed to sp-d exchange interaction. Photoluminescence data showed Co-doped CdS films had lower PL peak intensity than that of CdS, demonstrating a decrease in the number of intrinsic defects. Photovoltaic measurements displayed that the best efficiency of 0.488% was achieved for CdS-based device including 1% Co atoms, which were almost a seven-fold boost in overall efficiency compared to bare CdS-based device. The enhancement in power conversion efficiency originated from an increase in short-circuit current density of 1% Co-doped CdS-based photovoltaic cell.

(Invited) Characterization of Metal/GaN Schottky Contacts - Review from the Early Days

GaN-based materials have been intensively developed for blue light-emitting-diodes, blue laser diodes, power amplifiers in wireless base-stations, and high-power switching devices. Schottky contacts are one of the most important components in electron device fabrication. The electrical characteristics of GaN Schottky barrier contacts have been continuously studied for more than twenty years as improvement of GaN crystal quality and understanding physics of metal/semiconductor interfaces.In the early days, for the achievement of the high-power and high-temperature operation, thermally stable contacts were explored. Interfacial reactions and electrical characteristics were intensively examined by annealing studies for various kinds of metal contacts such as Ni, Pd, Pt, and Re. As a result of those, Ni has been widely used as a stable Schottky contact, because less thermal reaction with N atoms, high Schottky barrier height (qφ B), and good adhesion.As for the correlation with GaN crystal quality, in the early days, because a GaN epitaxial layer contained large-structure killer defects, rectifying characteristics were hardly observed in the Schottky contacts. Since after the n-GaN crystal quality improved with electron mobility over 100 cm2V−1 s−1, rectifying characteristics have been reproducibly obtained.[1] Even though the dislocation density was as high as 109–1010 cm−2 in epitaxial GaN layers, good current–voltage (I–V) characteristics and qφ B values below 1.1 eV were reported in Ni/n-GaN contacts. Moreover, in order to clarify the effect of dislocations on I–V characteristics, a 0.5-µm-diameter Schottky-dot array was formed on n-GaN grown by MOCVD, and I –V measurements were conducted using AFM with a conductive probe.[2] Neither mixed nor pure edge dislocations affected the I –V characteristics, but a large structural defect with a diameter of a few hundred nanometers shorted the contact.In addition, further improvement of the GaN layer grown on low dislocation (∼106 cm−2) free-standing GaN substrates provided ideal Schottky contacts with high qφ B values around 1.1 eV. It has been reported that the forward and reverse I–V characteristics of Ni contacts formed on hydride-vapor-phase-epitaxy grown n-GaN obeyed the thermionic emission and the thermionic field emission (TFE) models, respectively.[3] The same trend was also reported in nine different metal contacts on both c- and cleaved m-plane n-GaN crystals.[4] We also reported a post-metallization annealing at 400°C for 10 min was effective to reduce the reverse biased current significantly to the prediction by the TFE model.[5]Basic understanding of p-GaN Schottky contacts was slower than that of n-GaN, because p-GaN contacts were intensively studied for ohmic contacts of p-n-junction-base optical devices. In the early days, very leaky characteristics were reported and a reasonable qφ B value was not obtained. We improved leaky characteristics of Ni/p-GaN Schottky contacts by low Mg doping. The qφ B as high as 2.4 eV and the n-values of 1.8 were obtained from I –V.[6] We found a memory effect that carrier capture and emission from acceptor-like deep level defects caused depletion layer width to vary significantly.[7]Finally, as our original technique, scanning internal photoemission spectroscopy was developed to map the electrical characteristics of metal/semiconductor interfaces nondestructively.[8] We have demonstrated the mapping of characteristics for interfacial reactions of Ni/n-GaN at 400°C; degradation under applied voltage stress up to 45 V for vertical n-GaN contacts; and process induced surface damages by ion-implantation, dry etching, and photo-electrochemical etching.[9] This technique was confirmed to be useful for the development of the wide-bandgap-semiconductor high-power devices. K. Shiojima, J. Woodall, P. Grudowski, C. Eiting and R. Dupuis, J. Vac. Sci. Tech., B17(5), p. 2030 (1999).K. Shiojima, and T. Suemitsu, J. Vac. Scie. Tech., B21(2) p. 698(2003).J. Suda, K. Yamaji, Y. Hayashi, T. Kimoto, K. Shimoyama, H. Namita, and S. Nagao, Appl. Phys. Express, 3, p. 101003 (2010).H. Imadate, T. Mishima, and K. Shiojima, Jpn. J. Appl. Phys., 57, p. 04FG13 (2018).K. Shiojima, R. Tanaka, S. Takashima, K. Ueno, and M. Edo, Jpn. J. Appl. Phys., 60, 056503 (2021).K. Shiojima, T. Sugahara and S. Sakai, Appl. Phys. Lett., 74, p. 1936 (1999).K. Shiojima, T. Sugahara and S. Sakai, Appl. Phys. Lett. 77, p. 4353 (2000).T. Okumura and K. Shiojima, Jpn. J. Appl. Phys., vol. 28, p. L1108 (1989).K. Shiojima, ECS Transactions, 104, p. 69 (2021).

More than 60% RF loss reduction and improved crystal quality of GaN-on-Si achieved by in-situ doping tert-butylphosphorus

In this work, the parasitic conductive channel in a silicon substrate is compensated using in-situ doping for the first time. The experimental results show that in-situ doping of tert-butylphosphorus (TBP) has little adverse effect on the mobility and the density of two-dimensional electron gas but the compensation of the parasitic channel in the substrate is effective, and the aluminum nitride (AlN) / Si template based on the optimized conditions reduces the radio frequency loss by more than 60%. In addition, it was found that a suitable preflow of TBP can enhance the migration of Al atoms on the substrate surface and improve the crystal quality of gallium nitride (GaN), which reduces the dislocation density of GaN by 25% compared to the sample without TBP preflow. The hypothesis is that TBP preflow can affect the strain of the substrate, which makes the dislocations more likely to annihilate during the subsequent growth of AlN nucleation layer, resulting in the eventual improvement of GaN crystal quality.

HiPIMS-grown AlN buffer for threading dislocation reduction in DC-magnetron sputtered GaN epifilm on sapphire substrate

Gallium nitride (GaN) epitaxial films on sapphire (Al2O3) substrates have been grown using reactive magnetron sputter epitaxy with a liquid Ga target. Threading dislocations density (TDD) of sputtered GaN films was reduced by using an inserted high-quality aluminum nitride (AlN) buffer layer grown by reactive high power impulse magnetron sputtering (R-HiPIMS) in a gas mixture of Ar and N2. After optimizing the Ar/N2 pressure ratio and deposition power, a high-quality AlN film exhibiting a narrow full-width at half-maximum (FWHM) value of the double-crystal x-ray rocking curve (DCXRC) of the AlN(0002) peak of 0.086° was obtained by R-HiPIMS. The mechanism giving rise the observed quality improvement is attributed to the enhancement of kinetic energy of the adatoms in the deposition process when operated in a transition mode. With the inserted HiPIMS-AlN as a buffer layer for direct current magnetron sputtering (DCMS) GaN growth, the FWHM values of GaN(0002) and (10 1‾ 1) XRC decrease from 0.321° to 0.087° and from 0.596° to 0.562°, compared to the direct growth of GaN on sapphire, respectively. An order of magnitude reduction from 2.7 × 109 cm−2 to 2.0 × 108 cm−2 of screw-type TDD calculated from the FWHM of the XRC data using the inserted HiPIMS-AlN buffer layer demonstrates the improvement of crystal quality of GaN. The result of TDD reduction using the HiPIMS-AlN buffer was also verified by weak beam dark-field (WBDF) cross-sectional transmission electron microscopy (TEM).

Variation in thermal stability of Ge1−xSnx films for infrared device applications

We report on changes in Ge1−xSnx films (0.065 ≤ x ≤ 0.144) after short high-temperature anneals. Films were grown by molecular beam epitaxy on (001) Ge wafers, rapidly annealed, and characterized by x-ray diffraction, Raman spectroscopy, and optical microscopy. Sn segregated to the surface after a maximum temperature is inversely related to the Sn content. Lower content films showed little to no improvement in crystal quality below segregation temperatures, while higher content and partially relaxed films demonstrated improved uniformity for moderate annealing.

Fabrication of efficient and stable wide band gap CsPbIBr2 inorganic perovskite solar cells via doping with lead chloride compound

Currently, CsPbX3 (X = I, Br, Cl) wide bandgap inorganic perovskite solar cells (PSCs) with superior thermal stability and excellent photoelectric performance have received great attention in the photovoltaic community, showing great potential for the applications of tandem devices and building integrated photovoltaics (BIPV). Among them, CsPbIBr2 is considered as the most promising light-absorbing layers to balance performance and stability. However, its power conversion efficiency (PCE) is still lagging far behind other inorganic perovskites. It mainly attributes to the effect of sever intrinsic self-doping defect which always results in small grain size, low film coverage, and large carrier recombination. Herein, Lead Chloride (PbCl2) compound is firstly incorporated into CsPbIBr2 precursor solution to prepare CsPbIBr2−xClx wide bandgap films, and its optimal doping concentration is systematic studied in this work. Surprisingly, after the doping of PbCl2, the number of pinholes in perovskite films significantly decreased and impressive micron sized grains appeared. Besides, the improvement of crystal quality and the reduction of defect density effectively reduce the recombination of charge carriers inside the device. Hence, the optimized CsPbIBr2−xClx with a wide bandgap of 2.09 eV gains a PCE of 9.38 % and shows good thermal stability.

A novel method to optimize the growth of crystal silicon – Current assisted directional solidification

Large grain size and less impurity enrichment in polysilicon is always the key and difficult point for crystal quality improvement. In this work, polysilicon ingots were prepared by direct current (DC) assisted directional solidification. The Joule heat effect of DC was used to introduce a microscopic heat source which was directly acting on the solid–liquid interface front. The application of current regulates the thermal field distribution at the front of the solid–liquid interface, reduces the supercooling in the melt, and promotes lateral grain growth. The average grain size reached 297.62 μm at 55% solidification ratio, which got a 40.55% improvement compared to the ingots without current. In addition, the Joule heating effect can regulate the composition supercooling at the grooves and reduce the impurities in polysilicon ingots. In this paper, the mechanism of the effect of DC on crystal growth was investigated and the improvement of crystal size and the effect of impurity removal were achieved simultaneously.

Improvement of Mg-Doped GaN with Shutter-Controlled Process in Plasma-Assisted Molecular Beam Epitaxy

Mg-doped GaN was grown by plasma-assisted molecular beam epitaxy (PAMBE) on a Fe-doped GaN template substrate by employing a shutter-controlled process. The transition from n-type to p-type conductivity of Mg-doped GaN in relation to the N/Ga flux ratio was studied. The highest p-type carrier concentration in this series was 3.12 × 1018 cm−3 under the most N-rich condition. By modulating the shutters of different effusion cells for the shutter-controlled process, a wide growth window for p-type GaN was obtained. It was found that the presence of Mg flux effectively prevents the formation of structural defects in GaN epi-layers, resulting in the improvement of crystal quality and carrier mobility.

Isotopically Enriched Layers for Quantum Computers Formed by 28Si Implantation and Layer Exchange.

28Si enrichment is crucial for production of group IV semiconductor-based quantum computers. Cryogenically cooled, monocrystalline 28Si is a spin-free, vacuum-like environment where qubits are protected from sources of decoherence that cause loss of quantum information. Currently, 28Si enrichment techniques rely on deposition of centrifuged SiF4 gas, the source of which is not widely available, or bespoke ion implantation methods. Previously, conventional ion implantation into naturalSi substrates has produced heavily oxidized 28Si layers. Here we report on a novel enrichment process involving ion implantation of 28Si into Al films deposited on native-oxide free Si substrates followed by layer exchange crystallization. We measured continuous, oxygen-free epitaxial 28Si enriched to 99.7%. Increases in isotopic enrichment are possible, and improvements in crystal quality, aluminum content, and thickness uniformity are required before the process can be considered viable. TRIDYN models, used to model 30 keV 28Si implants into Al to understand the observed post-implant layers and to investigate the implanted layer exchange process window over different energy and vacuum conditions, showed that the implanted layer exchange process is insensitive to implantation energy and would increase in efficiency with oxygen concentrations in the implanter end-station by reducing sputtering. Required implant fluences are an order of magnitude lower than those required for enrichment by direct 28Si implants into Si and can be chosen to control the final thickness of the enriched layer. We show that implanted layer exchange could potentially produce quantum grade 28Si using conventional semiconductor foundry equipment within production-worthy time scales.

Growth Process and Optical Properties of Cs2ZrCl6 Doped with Ce3+ and Li+ Crystals

Cs2ZrCl6 (CZC) has very promising scintillation properties in the application of gamma-ray spectroscopy. So far, undoped crystals of this composition have been studied, but the growth of the large-scale doped single crystals has not been reported so far. In this paper, a process improvement strategy is reported. Large-scale Cs2ZrCl6:Ce,Li (CZC:Ce,Li) single crystals with excellent energy resolution are obtained by appropriately adjusting the temperature gradient and growth rate. CZC:Ce,Li single crystals doped with 0.5, 1.5, and 3.0 mol % Ce3+ were grown by the Bridgman method. After the phase purity of the sample was determined by X-ray diffraction analysis, the crystal defects were determined by the energy-dispersive X-ray spectroscopy, and the crystal growth process was improved on this basis. The transmission spectrum confirmed the improvement of crystal quality. The energy resolution of CZC:Ce,Li crystals grown by the improved process is 4.3%, which confirmed that the improved process is conducive to the growth of bulk doped CZC single crystals, and hence, our results provide a basis for the growth of large-scale doped CZC single crystals.

Manipulating the optoelectronic characteristic of AZO films by magnetron sputtering power

We investigated the effects of sputtering power on the structure, morphology, electrical and optical properties of AZO films. The results show that all the films show typical hexagonal wurtzite structure with preferred c-axis orientation. When the sputtering power is 120 W, the film has the smallest FHWH value and the largest grain size (24.33 nm), and the AZO thin films obtained the best conductivity, the electrical characteristic parameters are ρ = 3.25 × 10−3 Ω cm， N = 3.512 × 1019 cm−3, μH = 8.642 cm2V−1s−1, respectively. With the increase of sputtering power, the carrier concentration and hall mobility are increasing, which are directly related to the improvement of crystal quality, that is, the higher the crystal quality of the film, the better the conductivity. The average transmittance of all samples is above 80%, and the band gaps increase first and then decreased. This work implies that the application of controllable growth AZO transparent conductive film in photovoltaic devices.

Conversion efficiency improvement of ELO GaAs solar cell, deposited on water soluble sacrificial buffer

We demonstrate the improvement of power conversion efficiency of an epitaxially-lifted-off single junction GaAs solar cell deposited on a water-soluble sacrificial buffer architecture by introducing an additional germanium (Ge) interlayer between GaAs and the fluoride buffer. The epitaxial lift-off (ELO) technique has been extensively used to separate III-V device layers from their single crystal GaAs substrates. However, conventional ELO requires the use of concentrated hydrofluoric acid (HF) for extended times to etch out the sacrificial layer, subsequently degrading the surface roughness of the parent wafer. As a result, the wafer has to undergo expensive and intensive chemical mechanical polishing (CMP) processes, costing about 25 % of a pristine 6-inch GaAs substrate. In our previous work, we demonstrated a method to eliminating the need for CMP post-processing by using water-assisted ELO (H2O-ELO). A water-soluble, 3-layer buffer architecture was developed using alkaline earth compounds. However, devices suffered low performance due to a high defect density in the GaAs active layers. A Ge interlayer was introduced to provide a more favorable surface energy for GaAs growth, which leads to an improvement of GaAs crystal quality. The Ge deposition conditions were optimized to achieve a high-quality Ge layer on triple-layer fluoride buffer. Single junction GaAs devices fabricated on Ge/(Ca,Sr)F2/BaF2/(Ca,Sr)F2 showed improvement of solar cell performance parameters featuring increases in Voc by 23.7 %, and fill factor (F.F.) by 4.9 %, which results in an overall improvement of power conversion efficiency from 10.3 % to 12.69 %.

Influence of growth temperature and miscut angle of m-plane sapphire substrate on the semi-polar (11–22) AlN film grown by HVPE

The high-quality semi-polar (11-22) AlN thin films were grown on m-plane sapphire substrates by hydride vapor phase epitaxy (HVPE). The surface morphology and crystalline quality of the AlN film were greatly influenced by the growth temperature and the substrate miscut angle. As the temperature increased, the grain size on the surface increased and the grain density decreased. In addition, the higher growth temperature also resulted in smaller values of the full width at half maximum (FWHM) of X-ray rocking curves (XRC) when temperature was more than 1,460 °C. At high temperature of 1,530 °C, the introduction of 1° -off miscut angle to the substrate resulted in smooth surface, low density of stacking faults and low FWHM of XRC. The misfit dislocation density was calculated from the tilt angle of epilayer measured by X-ray reciprocal space mappings along [−1−123] AlN. The misfit dislocation density of the sample grown on 1° -off substrates was 6.7 × 105 cm−2. The improvement of crystal quality is believed to be due to the enhancement of adatom mobility at higher temperatures and also the appropriate miscut variation.

Crystal quality improvement of ZnTe (1 1 0) thin film prepared on sapphire by increasing nuclei density on substrate surface

ZnTe thin films were prepared on r, S-plane nanofacet substrates to achieve a high-crystal-quality layer with a (110) orientation. Scanning electron microscopy was used to study the nucleation process. Selective formation of growth nuclei can be achieved by controlling the substrate temperature. The low-temperature grown amorphous layers changed to nuclei by annealing. The surface amorphous layer was completely removed when the annealing temperature was too high. Zn beam irradiation during the annealing removed materials selectively from the r-nanofacet. Migration-enhanced epitaxy (MEE) was introduced to enlarge the nuclei size, and a thick-layer growth by conventional molecular beam epitaxy (MBE) followed. The MEE sequence was increased up to 1200 cycles, and the substrate temperature for MEE and MBE was set to higher temperatures than the conventional MBE substrate temperature (the conventional substrate temperature was around 340 °C). The crystal quality of the thin film was analyzed using the X-ray pole figure, θ–2θ measurements and photoluminescence. (110) oriented layer formation perpendicular to the substrate surface was confirmed after introducing those techniques. The low-temperature photoluminescence measurement indicated the high quality of the thick layer.

3D Network‐Assisted Crystallization for Fully Printed Perovskite Solar Cells with Superior Irradiation Stability

AbstractMeniscus‐coating as a high‐throughput preparation process has significant advantages in the manufacture of large‐area perovskite solar cells (PSCs). However, the gradient crystallization during printing significantly affects the vertical uniformity of perovskite films, which greatly affects the carrier transport of perovskite films and the stability of PSCs. Here, a perovskite ink compatible with printing technology is reported to realize uniform printing of perovskite film on a 3D scale. The siloxane 3D network hinders the solute migration caused by capillary force and acts as a skeleton to promote the uniform crystallization of perovskite films. Consequently, the corresponding fully printed PSCs have reduced efficiency loss (from 37.4% to 17.0%). In addition, based on the improvement of crystal quality and reduction of defects in perovskite films, the siloxane‐optimized PSCs achieved a championship efficiency of 22.0%, which is one of the highest performance for fully printed devices. The optimized device retains 80% of the initial PCE after 800 h AM 1.5G one‐sun illumination, and only decreases 20% after 160 h of ultraviolet light (365 nm, 20 mW cm−2) irradiation.

Suppression and compensation effect of oxygen on the behavior of heavily boron-doped diamond films

This work investigates the suppression and compensation effect of oxygen on the behaviors and characteristics of heavily boron-doped microwave plasma chemical vapor deposition (MPCVD) diamond films. The suppression effect of oxygen on boron incorporation is observed by an improvement in crystal quality when oxygen is added during the diamond doping process. A relatively low hole concentration is expected and verified by Hall effect measurements due to the compensation effect of oxygen as a deep donor in diamond. A low acceptor concentration, high compensation donor concentration and relatively larger acceptor ionization energy are then induced by the incorporation of oxygen; however, a heavily boron-doped diamond film with high crystal quality can also be expected. The formation of an oxygen–boron complex structure instead of oxygen substitution, as indicated by the results of x-ray photoelectron spectroscopy, is suggested to be more responsible for the observed enhanced compensation effect due to its predicted low formation energy. Meanwhile, density functional theory calculations show that the boron–oxygen complex structure is easily formed in diamond with a formation energy of –0.83 eV. This work provides a comprehensive understanding of oxygen compensation in heavily boron-doped diamond.

The Effect of Si (111) Substrate Surface Cleaning on Growth Rate and Crystal Quality of MOVPE Grown AlN

In this work, the effect of Si (111) substrate surface cleaning by RCA (Radio Corporation of America) method on growth rate and crystalline quality of epitaxially grown AlN thin films by MOVPE (Metal Organic Vapor Phase Epitaxy) technique is investigated. In situ reflectance system and high resolution X-ray diffraction (HRXRD) technique are used for the analysis of growth rate and crystal quality of epitaxial AlN layers, respectively. Also, The Raman measurement is done to show the effect of the RCA cleaning procedure on the position of the peaks that occurred in the Raman spectra. The results have shown that the surface cleaning of Si (111) substrate by the RCA method removes the oxide layer formed on the surface, also helps to decrease the parasitic reactions and increases the adatom efficiency, results in an increased growth rate of the AlN layer. Besides, surface cleaning of Si (111) substrate by the RCA method has reduced the FWHM value ~5% for ω-2θ scan and ~60% for ω scan of AlN epilayer, indicating an improvement in crystal quality.

Realization of UV-C absorption in ZnO nanostructures using fluorine and silver co-doping

In this study, we realized absorption in UV-C region using silver (Ag) and fluorine (F) co-doping in zinc oxide (ZnO). Also, the influence of Ag and F co-doping in ZnO on the morphological, compositional, structural, and optical properties using the hydrothermal method were investigated. The result shows that vertically aligned nanorods (NRs) of different dimensions were observed using field emission scanning electron microscopy (FESEM). Wurtzite hexagonal structure and polycrystalline nature of the samples were confirmed through X-ray diffraction (XRD) analysis. The crystallite size increased from 29.92 to 35.81 nm and microstrains values were decreased upon co-doping. Energy dispersive X-ray (EDX) analysis confirmed the existence of zinc, oxygen, silver, fluorine, and oxygen deficiency in all the studied samples. Ultra-violet (UV) visible analysis has shown a decrement in the optical energy bandgap from 3.273 to 3.179 eV upon co-doping with the appearance of two absorption edges. The additional optical characteristics comprising absorption coefficient (α), skin depth, optical density (OD), extinction coefficient (k) were also explained. Photoluminescence (PL) analysis has shown that the ZnO native visible defects were suppressed significantly upon co-doping, showing crystal quality improvement as revealed by XRD analysis.