Optoelectronic Components Research Articles

Synthesis and Optical Properties of 2-(4-trifluoromethylphenyl)-3-(4-methoxyphenyl) Acrylonitrile (4MPAN-TFMP) Compounds

The 2-(4-Trifluoromethylphenyl)-3-(4-methoxyphenyl) acrylonitrile (4MPAN-TFMP) compound was successfully synthesized and characterized using standard spectroscopic methods. Thin films of 4MPAN-TFMP were prepared by conventional spin-coating, with varying film thicknesses to investigate the thickness-dependent optical and photonic properties. UV-Vis spectra of the compounds in DMSO were recorded, and key parameters such as absorption (Abs), transmittance (T), absorption band edge (EAbs-be), optical band gap (Eg), and refractive index (n) were determined. The findings highlight the material’s potential for optoelectronic applications, as optimized film thicknesses can enhance material efficiency for various uses. This advancement offers promising implications for developing high-performance photonic devices and improving optoelectronic circuit components.

Influence of solid loading on microstructure evolution and thermal conductivity of aluminum nitride ceramics fabricated by digital light processing 3D printing

Efficient thermal management is essential to reduce hot spot temperature of high-power opto-electronic components and improve their working efficiency. In this work, AlN ceramics with high density and thermal conductivity properties were fabricated using a joint process of digital light processing (DLP) 3D printing and micro-pressure-assisted sintering method. Effects of solid loading on microstructure evolution and thermal properties of the ceramics were systematically discussed. AlN ceramic mini-channel heat sinks were designed and fabricated using the optimized DLP 3D printing and sintering parameters. The thermal management performances of the ceramic heat sinks were evaluated by investigating the optoelectronic property of the encapsulated laser diode module. Results indicated that the laser diode module could be long-timely operated at full driven power. This study provided a new strategy for fabricating high performance AlN ceramics with complex configurations and highlighted the technical potential of AlN ceramic heat sink with compact coolant channels.

Fluorescent Protein PEGylation for Stable Photon Manipulation in Deep‐Red Light‐Emitting Devices

AbstractPEGylation is a classic strategy to reduce denaturation and immunogenicity in therapeutic proteins, bioimaging, and drug delivery. However, this concept has not been applied to incorporate biogenic materials as functional components in optoelectronics. Herein, PEGylation is rationalized as an effective tool to stabilize fluorescent proteins in solid‐state photon manipulation down‐converters integrated into bio‐hybrid light‐emitting diodes. In short, the archetypal red‐emitting protein mCherry is nonspecifically PEGylated with methoxypolyethylene glycols (mPEG) chains of different lengths (mPEG‐350/‐750/‐2000). These derivatives hold the same photoluminescence figures‐of‐merit of mCherry, but an improved resistance against organic solvents, pH, temperature, and polymers (in solution/dry‐coatings) upon increasing the mPEG length. Indeed, the best‐performing mCherry‐mPEG‐2000 adduct leads to deep‐red devices with threefold enhanced color stability (>300 h) under harsh operation conditions (150 mW cm−2) over the prior art. Different device architectures along with spectroscopic, thermocycling, and electrochemical impedance spectroscopy studies of the prepared coatings aid in rationalizing that PEGylation successfully reduces i) nonreversible thermal denaturation, ii) aggregation in solid‐state, and iii) photo‐induced oxidation and H+‐transfer deactivation of the chromophore, since oxygen diffusivity and H+‐reorganization across the protein skeleton are slowed down by strong H+‐bonding/hydrophobic mCherry‐mPEG interactions. Hence, this simple supramolecular modification is of utmost relevance for future advances in protein‐based optoelectronics.

Stretchable wireless optoelectronic synergistic patches for effective wound healing

Physiotherapies play a crucial role in noninvasive tissue engineering for wound healing. However, challenges such as the implementation of complex interventions and unsatisfactory treatment outcomes impede widespread application. Here, we proposed a stretchable and wirelessly-powered optoelectronic synergistic patch with a dual-layer serpentine wireless receiver circuit to drive the optoelectronic modulation component. Optimized structure and impedance matching enable the patch to seamlessly attach to irregular skin surfaces and operate robustly over a 30% tensile strain range. Based on Sprague-Dawley rat wound model. The wound closure rate of the optoelectronic synergistic group significantly outperformed both monointervention and blank control groups. Mechanistically, optoelectronic synergistic intervention enhances the secretion of vascular endothelial marker proteins and growth factors, and stabilizes mitochondrial function during oxidative stress. Overall, the scalable amalgamation of flexible electronics, wireless transmission, and synergistic interventions promise to improve wound care.

Photoinduced charge separation at heterojunctions between two-dimensional layered materials and small organic molecules.

p-n heterojunctions are fundamental components for electronics and optoelectronics, including diodes, transistors, sensors, and solar cells. Over the past few decades, organic-inorganic p-n heterojunctions have garnered significant interest due to the diverse properties they exhibit, which are a result of the limitless combinations of organic molecules and inorganic materials. This review article concentrates on photoinduced charge separation and photocurrent generation at heterojunctions between two-dimensional layered materials and structurally well-defined organic small molecules. We highlight representative examples, including our work, and critically discuss their potential and perspectives.

Quantitative photocurrent scanning probe microscopy on PbS quantum dot monolayers.

Photoconductive atomic force microscopy can probe monolayers of PbS/perovskite quantum dots (QDs) with a contact area of 1-3 QDs in stable and reproducible acquisition conditions for I/V curves and photocurrent maps. From the measurements, quantitative values for the barrier height, built-in voltage, diffusion constant and ideality factor are deduced with high precision. The data analysis is based on modelling a superposition of the drift current of the photo-excited charges and a diffusion current across the interface barriers, providing physical insight into the underlying processes. Besides looking into PbS/perovskite on an indium tin oxide substrate, it is shown how the photocurrent is modified by changing either the QD ligand (to thiocyanate) or the substrate (to micro- and nanostructured gold). The dependence of the photocurrent on the light irradiance is found to follow a power law with an exponent of 0.64. Generally, quantitative measurements with high spatial resolution (on the single QD level) can provide significant insight into the processes in nanostructured hybrid optoelectronic components.

Strength and Electrostatic Discharge Resistance Analysis of Additively Manufactured Polyethylene Terephthalate Glycol (PET-G) Parts for Potential Electronic Application.

Optoelectronic components are crucial across various industries. They benefit greatly from advancements in 3D printing techniques that enable the fabrication of intricate parts. Among these techniques, Material Extrusion (MEX) stands out for its simplicity and cost-effectiveness. Integrating 3D printing into production processes offers the potential to create components with enhanced electrostatic discharge (ESD) resistance, a critical factor for ensuring the reliability and safety of optoelectronic devices. Polyethylene terephthalate glycol-modified (PET-G) is an amorphous copolymer renowned for its high transparency, excellent mechanical properties, and chemical resistance, which make it particularly suitable for 3D printing applications. This study focuses on analyzing the mechanical, structural, and electrostatic properties of pure PET-G as well as PET-G doped with additives to evaluate the effects of doping on its final properties. The findings highlight that pure PET-G exhibits superior mechanical strength compared to doped variants. Conversely, doped PET-G demonstrates enhanced resistance to electrostatic discharge, which is advantageous for applications requiring ESD mitigation. This research underscores the importance of material selection and optimization in 3D printing processes to achieve desired mechanical and electrical properties in optoelectronic components. By leveraging 3D printing technologies like MEX and exploring material modifications, industries can further innovate and enhance the production of optoelectronic devices, fostering their widespread adoption in specialized fields.

Design and Implementation of a Photonic-Based Electronic Warfare System

Nowadays, the Radio frequency (RF) Photonics become an inevitable candidate to address several military related potential applications including electronic warfare (EW), photonic signal processing (PSP), photonic-based RF transportation, and photonic communications. As part of this emerging technology development/requirement, we designed a photonic-based EW systems (PEWS) in the optisystem environment (later implemented using optoelectronic components) to extract various radar waveforms such as continuous wave (CW), pulsed wave, and frequency/phase modulated wave. All these radar waveforms are transmitted and captured by the proposed/implemented PEW system, and then processed to construct the radar signatures from its electromagnetic (EM) spectrum/signals. The key parameters of various waveforms generated and processed in our research work are varied, over the time, during the performance validation tests. The values of key parameters of the waveforms: RF CW signal frequencies, pulse repetition times (PRTs), pulse-widths, Barker code phase modulations, Frank code poly-phase modulations, sweep frequencies, and RF power levels; are 100 Hz through 8 GHz, 10 ms through 2 µs, 750 ns through 2 ns, 0o /80o, 0o /90o /180o /270o, and -84 dBm through 30 dBm, respectively. The details of PEWS design approaches, their implementation methodologies, and different performance validation experimental results are reported, and analyzed. The limitations, and possible immediate research contributions/requirements are also listed.

Raman Investigation on Silicon Nitride Chips after Soldering onto Copper Substrates.

The unique electrical properties of silicon nitride have increased the applications in microelectronics, especially in the manufacture of integrated circuits. Silicon nitride is mainly used as a passivation barrier against water and sodium ion diffusion and as an electrical insulator between polysilicon layers in capacitors. The interface with different materials, like semiconductors and metals, through soldering may induce residual strains in the final assembly. Therefore, the dentification and quantification of strain becomes strategically important in optimizing processes to enhance the performance, duration, and reliability of devices. This work analyzes the thermomechanical local strain of semiconductor materials used to realize optoelectronic components. The strain induced in the β-Si3N4 chips by the soldering process performed with AuSn pre-formed on copper substrates is investigated by Raman spectroscopy in a temperature range of -50 to 180 °C. The variation in the position of the E1g Raman peak allows the calculation of the local stress present in the active layer, from which the strain induced during the assembly process can be determined. The main reason for the strain is attributed to the differences in thermal expansion coefficients among the various materials involved, particularly between the chip, the interconnection material, and the substrate. Micro-Raman spectroscopy allows for the assessment of how different materials and assembly processes impact the strain, enabling more informed decisions to optimize the overall device structure.

Structural and optical properties of green-synthesised tricobalt tetroxide nanoparticles

In this study, we investigated the structural and optical properties of garlic extract-based green-synthesised tricobalt tetroxide nanoparticles. Transmission electron microscopy revealed a particle size range of 8–22 nm for the prepared powder sample. Powder x-ray diffraction data and Rietveld refinement results confirmed the spinel cubic crystal structure of the tricobalt tetroxide nanoparticles, with an average crystallite size of 11.23 nm. This crystal structure corresponds to the Fd3̅m space group and has an average lattice constant of 0.791 nm. The bond lengths of Co3+–O2− and Co2+–O2− are measured to be 0.188 nm and 0.190 nm, respectively. The FTIR data provided evidence of the presence of various functional bands, which helped qualitatively determine the purity of the sample. The UV–vis spectrum estimated two direct energy band gap values (3.7 eV and 2.2 eV) that may be useful for efficient interaction with a wide range of ray spectra to create more electron–hole pairs for various photo-responsive applications, such as dye degradation, solar cells, and optoelectronic components.

Molecular Packing Topology and Interactions to Decipher Mechanical Compliances in Dicyano-Distyrylbenzene Derivatives.

Flexible optoelectronics is the need of the hour as the market moves toward wearable and conformable devices. Crystalline π-conjugated materials offer high performance as active materials compared to their amorphous counterpart, but they are typically brittle. This poses a significant challenge that needs to be overcome to unfold their potential in optoelectronic devices. Unveiling the molecular packing topology and identifying interaction descriptors that can accommodate strain offers essential guiding principles for developing conjugated materials as active components in flexible optoelectronics. The molecular packing and interaction topology of eight crystal systems of dicyano-distyrylbenzene derivatives are investigated. Face-to-face π-stacks in an inclined orientation relative to the bending surface can accommodate expansion and compression with minimal molecular motion from their equilibrium positions. This configuration exhibits good compliance towards mechanical strain, while a similar structure with a criss-cross arrangement capable of distributing applied strain equally in opposite directions enhances the flexibility. Molecular arrangements that cannot reversibly undergo expansion and compression exhibit brittleness. In the isometric CT crystals, the disproportionate strength of the interactions along the bending plane and orthogonal directions makes these materials sustain a moderate bending strain. These results provide an updated explanation for the elastic bending in semiconducting π-conjugated crystals.

Defect Engineering of MoTe2 via Thiol Treatment for Type III van der Waals Heterojunction Phototransistor.

Molybdenum ditelluride (MoTe2) nanosheets have displayed intriguing physicochemical properties and opto-electric characteristics as a result of their tunable and small band gap (Eg ∼ 1 eV), facilitating concurrent electron and hole transport. Despite the numerous efforts devoted to the development of p-type MoTe2 field-effect transistors (FETs), the presence of tellurium (Te) point vacancies has caused serious reliability issues. Here, we overcome this major limitation by treating the MoTe2 surface with thiolated molecules to heal Te vacancies. Comprehensive materials and electrical characterizations provided unambiguous evidence for the efficient chemisorption of butanethiol. Our thiol-treated MoTe2 FET exhibited a 10-fold increase in hole current and a positive threshold voltage shift of 25 V, indicative of efficient hole carrier doping. We demonstrated that our powerful molecular engineering strategy can be extended to the controlled formation of van der Waals heterostructures by developing an n-SnS2/thiol-MoTe2 junction FET (thiol-JFET). Notably, the thiol-JFET exhibited a significant negative photoresponse with a responsivity of 50 A W-1 and a fast response time of 80 ms based on band-to-band tunneling. More interestingly, the thiol-JFET displayed a gate tunable trimodal photodetection comprising two photoactive modes (positive and negative photoresponse) and one photoinactive mode. These findings underscore the potential of molecular engineering approaches in enhancing the performance and functionality of MoTe2-based nanodevices as key components in advanced 2D-based optoelectronics.

Applying the first principle to study the structure, electrical and magnetic properties of ASiNRs-doped Neodymium

In this project, we investigated and investigated the optimal sites in the chemisorption of Neodymium (Nd) on armchair silicene nanoribbons (ASiNRs) to learn about the geometrical and electronic properties of the structures by applying these properties with first principle math. The survey has three steps. The first was to change the top, valley, bridge, and hollow positions to find optimazed positionThe results show that the Bridge position has the lowest absorbed energy value of -2.6eV, has the most stable structure, with the strongest magnetic moment of 4.68 μB, and a buckl degree of 0.69 Å; The Si-Si-Si bond angle at this time is 115053’ almost like the pristine case. The second was to change the Si-Si bondlength of ASiNRs the same purpose. Finally, we survey the distance from Nd atom to pristine adsorbent surface was decreased. The calculation results show that the valley position is the most ideal location, corresponding to the bond length of 2.26 Å and the optimal height of 2.11 Å resulting in a single material adsorption system for the new materials, different from other positions with bandgap changed. This result shows that the absorption method between metals and pristine semiconductor ASiNRs has opened up a very good direction, contributing to enriching the source of materials applied to the field of manufacturing electronic, optoelectronic, and spintronic components in the future.

Ultra-fast perovskite electro-optic modulator and multi-band transmission up to 300 Gbit s−1

The gap between the performance of optoelectronic components and the demands of fiber-optic communications has narrowed significantly in recent decades. Yet, the expansion of data communications traffic remains substantial, with fiber-link speeds increases anticipated in the near future. Here, we demonstrate an ultra-high-speed electro-optic waveguide modulator constructed using a thin film of lanthanum-modified lead zirconate titanate with a ferroelectric phase exhibiting a strong Pockels effect. The modulator has a wide optical window; thus, the modulation was demonstrated for 1550 and 1310 nm wavelengths. This device showed electro-optical intensity signaling with line rates of 172 Gbit s−1, in conjunction with on–off keying modulation; this performance could be increased to 304 Gbit s−1 using four-level pulse modulation. The signaling performance of this modulator was found to be robust, with stable performance at temperatures as high as 100 °C. This technology is expected to have applications in a wide range of classical optoelectronic devices and in quantum science and technology.

Use of a platform with lens-free shadow imaging technology to monitor natural killer cell activity

Natural killer (NK) cells are a crucial component of the innate immune system. This study introduces Cellytics NK, a novel platform for rapid and precise measurement of NK cell activity. This platform combines an NK-specific activation stimulator cocktail (ASC) and lens-free shadow imaging technology (LSIT), using optoelectronic components. LSIT captures digital hologram images of resting and ASC-activated NK cells, while an algorithm evaluates cell size and cytoplasmic complexity using shadow parameters. The combined shadow parameter derived from the peak-to-peak distance and width standard deviation rapidly distinguishes active NK cells from inactive NK cells at the single-cell level within 30 s. Here, the feasibility of the system was demonstrated by assessing NK cells from healthy donors and immunocompromised cancer patients, demonstrating a significant difference in the innate immunity index (I3). Cancer patients showed a lower I3 value (161%) than healthy donors (326%). I3 was strongly correlated with NK cell activity measured using various markers such as interferon-gamma, tumor necrosis factor-alpha, perforin, granzyme B, and CD107a. This technology holds promise for advancing immune functional assays, offering rapid and accurate on-site analysis of NK cells, a crucial innate immune cell, with its compact and cost-effective optoelectronic setup, especially in the post-COVID-19 era.

Investigation for AGZO RRAM using the RF Co-sputtering method

Recently, the Internet of Things (IOT) has rapidly developed, leading to the development of many smart devices. Moreover, artificial intelligence (AI) and 5G communication are successful, and the demand for high-performance memory is increasing. The emerging nonvolatile RRAM has many advantages, such as low power consumption, fast operation speed, simple structure and excellent scalability, compared with traditional memories; this is promising for complex computing and mass storage. Zinc oxide (ZnO) is a promising candidate for transparent conducting oxide (TCO) applications because of its abundance, high conductivity, low toxicity, and cost-effectiveness. It is currently used in various optoelectronic components including thin-film transistors (TFTs) and photodetectors. Notably, TCO has been increasingly used in the switching layers of random resistive access memory systems. In this paper, we intend to combine AGO with a large energy gap and ZnO with a high conductivity to prepare AGZO as a switching layer for RRAM by co-sputtering. By adjusting the oxygen flow ratio and power of co-sputtering, the AGZO RRAM exhibited high performance with more than 1400 switching cycles, 102–103 on/off ratio, and low operation voltage, and high- and low-resistance states could be maintained for more than 10,000[Formula: see text]s.

Picosecond carrier dynamics in InAs and GaAs revealed by ultrafast electron microscopy.

Understanding the limits of spatiotemporal carrier dynamics, especially in III-V semiconductors, is key to designing ultrafast and ultrasmall optoelectronic components. However, identifying such limits and the properties controlling them has been elusive. Here, using scanning ultrafast electron microscopy, in bulk n-GaAs and p-InAs, we simultaneously measure picosecond carrier dynamics along with three related quantities: subsurface band bending, above-surface vacuum potentials, and surface trap densities. We make two unexpected observations. First, we uncover a negative-time contrast in secondary electrons resulting from an interplay among these quantities. Second, despite dopant concentrations and surface state densities differing by many orders of magnitude between the two materials, their carrier dynamics, measured by photoexcited band bending and filling of surface states, occur at a seemingly common timescale of about 100 ps. This observation may indicate fundamental kinetic limits tied to a multitude of material and surface properties of optoelectronic III-V semiconductors and highlights the need for techniques that simultaneously measure electro-optical kinetic properties.

Exploring structural, optoelectronic, and thermoelectric properties of SrCaGe and SrCaSn half Heusler compounds

AbstractMaking products that are affordable, environmentally friendly, and energy‐efficient is the main objective of modern production. The objective of this research is to discover compounds that meet these parameters. The full‐potential, linearized augmented plane wave program (FP LAPW) offered by Wien2K was used to examine the structural, optical, electrical, and transport aspects of SrCaGe and SrCaSn Half‐Heusler (HHs) compounds. Generalized gradient approximation (GGA) was considered for the structural optimization and computation of elastic properties signifies inherent ductility and mechanical stability of the examined SrCaGe and SrCaSn compounds. Additionally, both materials were found to possess a direct bandgap and exhibit semiconducting behavior. The bandgap magnitudes obtained utilizing the modified Becke‐Johnson (mBJ) approximation are 0.78 and 0.52 eV for SrCaGe and SrCaSn, respectively. According to their optical characteristics, SrCaGe and SrCaSn show potential for application in optoelectronic components. Furthermore, the transport properties are evaluated by BoltzTrap program, revealing that both SrCaGe and SrCaSn exhibit figures of merit (ZT) values nearly equal to one at room temperature. This suggests their potential use in creating thermoelectric devices with highly efficient performance. The simulation study demonstrates the promising attributes of SrCaGe and SrCaSn HHs materials, positioning them as viable candidates for various applications, aligned with the goals of sustainable and efficient manufacturing.

Metasurface-enabled barcoding for compact flow cytometry

Flow cytometers are a vital tool for cellular phenotyping but are primarily limited to centralized laboratories due to their bulkiness and cost. Significant efforts have been made to construct on-chip flow cytometers for point-of-care applications, and a promising approach is filter-on-chip flow cytometers utilizing the conventional Bayer RGB filter on imaging cameras to miniaturize key optoelectronic components. However, conventional RGB filters fail to provide spectral channels of sufficient diversity and specificity for accurate identification of fast-moving fluorescence signals. Here, we present an optofluidic system with integrated metasurfaces that serve to increase the number and diversity of the spectral channels. Inverse design of spatially coded metasurfaces is used to maximize the classification accuracy of spectral barcodes generated along the particle trajectory obtained from single-shot imaging. The accuracy of this system is shown to be superior to generic RGB filter approaches while also realizing classification of up to 13 unique combinations of fluorophores, significantly enhancing the capability of portable flow cytometers.

Accuracy of coordinate measurements at phase modulation by digital raster

The development of optical-electronic instruments for measuring linear and angular quantities based on focal-plane array (photomatrices) using a digital phase analyzer (digital raster) is considered. It is shown that, unlike a phase raster with a mechanical drive, a digital raster provides the possibility of automation and increased measurement accuracy, reducing the weight and size characteristics of the measuring instrument. A method for constructing a digital raster is proposed, based on the use of photomatrices in combination with computer technologies. To ensure the required accuracy of the developed opto-electronic devices, the sources and components of the measurement error were investigated. The influence of the discrete structure of a digital raster on the error in measuring image coordinates has been studied. Mathematical expressions are obtained for calculating the limiting values of coordinate measurement errors caused by parasitic phase modulation that occurs when using a digital raster (sampling error). The dependence of these errors on image parameters and pixel size has been determined. It is shown that, based on the permissible maximum sampling error, it is possible to calculate the required dimensions of a photomatrix pixel, while the size of the sampling pixel can be larger than the size of the photomatrix pixel, which is very signifi cant from the point of view of energy relations. The results obtained will be useful in the development of optical-electronic means of angular and linear measurements with digital rasters.