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Tin oxide (SnO2) has garnered significant attention for its high spectral selectivity when used as an ultraviolet photodetector (PD). In this study, SnO2 nanosheets (NSs) were synthesized via a hydrothermal method, followed by spin-coating a layer of Ga2O3 thin film to construct a heterojunction photoelectrochemical ultraviolet PD (PEC UV PD). Initially, we investigated the effect of precursor composition on the properties of the Ga2O3 thin films. It was observed that the thickness of the films increased with higher precursor concentrations, while the optical bandgap decreased. Based on these findings, we successfully fabricated the SnO2 NSs-Ga2O3 PEC UV PD. Electrochemical analysis revealed that as the precursor concentration used for spin-coating Ga2O3 increased, the device's responsivity and detectivity initially increased and then decreased. After optimization, the device prepared with a 0.2 M Ga(NO3)3 solution spin-coated on SnO2 exhibited excellent spectral selectivity (R 265nm/ R 420nm ∼ 4472), a responsivity of 4.86 mA W−1, and a detectivity of 2.72 × 109 Jones. This study demonstrates that coating Ga2O3 is an effective approach to constructing high-performance SnO2-based UV PDs. [ABSTRACT FROM AUTHOR]

The praseodymium-doped indium zinc oxide (PrIZO) thin-film transistor (TFT) is promising for applications in flat-panel displays, due to its high carrier mobility and stability. Nevertheless, there are few studies on the mechanism of annealing on PrIZO films and the fabrication of flexible devices. In this work, we first optimized the annealing-process parameters on the glass substrate. As the annealing temperature rises, the film tends to be denser and obtains a lower surface roughness, a narrower optical-band gap and less oxygen-vacancy content. However, the μ-PCD test shows the 250 °C-annealed film obtains the least defects. And the PrIZO TFT annealed at 250 °C exhibited a desired performance with a saturation mobility (μsat) of 14.26 cm2·V−1·s−1, a subthreshold swing (SS) of 0.14 V·dec−1, an interface trap density (Dit) of 3.17 × 1011, an Ion/Ioff ratio of 1.83 × 108 and a threshold voltage (Vth) of −1.15 V. The flexible devices were prepared using the optimized parameters on the Polyimide (PI) substrate and subjected to static bending tests. After bending at a radius of 5 mm, the mobility of devices decreases slightly from 12.48 to 10.87 cm2·V−1·s−1, demonstrating the great potential of PrIZO for flexible displays. [ABSTRACT FROM AUTHOR]

The representation and utilization of environmental information by service robots has become increasingly challenging. In order to solve the problems that the service robot platform has, such as high timeliness requirements for indoor environment recognition tasks and the small scale of indoor scene data, a method and model for rapid classification of household environment domain knowledge is proposed, which can achieve high recognition accuracy by using a small-scale indoor scene and tool dataset. This paper uses a knowledge graph to associate data for home service robots. The application requirements of knowledge graphs for home service robots are analyzed to establish a rule base for the system. A domain ontology of the home environment is constructed for use in the knowledge graph system, and the interior functional areas and functional tools are classified. This designed knowledge graph contributes to the state of the art by improving the accuracy and efficiency of service decision making. The lightweight network MobileNetV3 is used to pre-train the model, and a lightweight convolution method with good feature extraction performance is selected. This proposal adopts a combination of MobileNetV3 and transfer learning, integrating large-scale pre-training with fine-tuning for the home environment to address the challenge of limited data for home robots. The results show that the proposed model achieves higher recognition accuracy and recognition speed than other common methods, meeting the work requirements of service robots. With the Scene15 dataset, the proposed scheme has the highest recognition accuracy of 0.8815 and the fastest recognition speed of 63.11 microseconds per sheet. [ABSTRACT FROM AUTHOR]

High-k metal oxides are gradually replacing the traditional SiO2 dielectric layer in the new generation of electronic devices. In this paper, we report the production of five-element high entropy metal oxides (HEMOs) dielectric films by solution method and analyzed the role of each metal oxide in the system by characterizing the film properties. On this basis, we found optimal combination of (AlGaTiYZr)Ox with the best dielectric properties, exhibiting a low leakage current of 1.2 × 10−8 A/cm2 @1 MV/cm and a high dielectric constant, while the film's visible transmittance is more than 90%. Based on the results of factor analysis, we increased the dielectric constant up to 52.74 by increasing the proportion of TiO2 in the HEMOs and maintained a large optical bandgap (>5 eV). We prepared thin film transistors (TFTs) based on an (AlGaTiYZr)Ox dielectric layer and an InGaZnOx (IGZO) active layer, and the devices exhibit a mobility of 18.2 cm2/Vs, a threshold voltage (Vth) of −0.203 V, and an subthreshold swing (SS) of 0.288 V/dec, along with a minimal hysteresis, which suggests a good prospect of applying HEMOs to TFTs. It can be seen that the HEMOs dielectric films prepared based on the solution method can combine the advantages of various high-k dielectrics to obtain better film properties. Moreover, HEMOs dielectric films have the advantages of simple processing, low-temperature preparation, and low cost, which are expected to be widely used as dielectric layers in new flexible, transparent, and high-performance electronic devices in the future. [ABSTRACT FROM AUTHOR]

[Objective] The preparation of luminescent display pixels using inkjet printing technology offers significant advantages, including low cost, flexibility, and the potential for large-scale production. This approach effectively reduces the production cost of OLED displays. The process of inkjet printing organic light-emitting layers is particularly crucial and complex. It requires designing and optimizing driving waveforms to achieve stable droplet formation without satellite points. Additionally, the printing line width and thickness must be adjusted to produce a dense and uniform thin film. Before preparing display pixels, it is essential to observe the inkjet droplets and assess their stability. However, changes in driving waveform parameters, ink ratio, or printing temperature can affect various parameters, including ink droplet uniformity, stability, volume, and injection speed--changes that are often undetectable by the naked eye. [Methods] This study investigates an automatic measurement technology for inkjet droplet parameters. A droplet-driving waveform customization module has been integrated into LabVIEW software using the NI Vision visual development module. This optimization of the droplet-driving waveform aims to achieve perfect jet droplets. The droplet image is captured using phase delay technology, which employs two control signals of the same frequency and a constant phase difference. One signal is the droplet drive signal, while the other is a square wave signal that triggers the camera and strobe light source. When the first driving waveform from the nozzle arrives, another signal is output as a pulse square wave after a delay of Δt. At this moment, the strobe light source activates, and the camera captures an image of the ink droplet. When the nozzle continuously sprays ink droplets at a fixed frequency, Δt remains constant, resulting in multiple images captured by the camera that maintain consistency, giving the appearance that the ink droplets are stationary in the air. By varying the delay time Δt between the two signals, the position of the ink droplets changes, allowing for the simulation of the dynamic falling process of the ink droplets. [Results] Droplet images are obtained at different times with a phase delay of Δt = 10 µs, capturing a complete spraying process. The images undergo filter denoising, binary conversion, morphological operations, and edge detection to obtain clear droplet contours. The volume of the ink droplets is calculated using an integral formula, and the diameter of the droplets is further determined using the spherical volume formula. The spray speed of the droplets is calculated based on the differences in ink droplet positions across multiple frames of images. [Conclusions] This research on automatic measurement technology for inkjet droplet parameters has resulted in the development of a hardware device for droplet observation, with a software control system implemented in LabVIEW graphical programming language. Droplet images are captured at different times with a phase delay of Δt=10 µs. Each image undergoes filtering, denoising, binary conversion, morphological operations, and edge detection to obtain clear droplet contours, thereby capturing a complete spraying process. The effective extraction of droplet contours, along with the automatic calculation of droplet spraying speed, diameter, and volume parameters, provides a visualization tool for optimizing ink preparation and inkjet printing, thereby facilitating the production of high-quality films. [ABSTRACT FROM AUTHOR]

As the competition intensifies in enhancing the integration and performance of integrated circuits, in accordance with the famous Moore's Law, higher performance and smaller size requirements are imposed on the dielectric layers in electronic devices. Compared to vacuum methods, the production cost of preparing dielectric layers via solution methods is lower, and the preparation cycle is shorter. This paper utilizes a low-temperature self-exothermic reaction based on the solution method to prepare high-performance Al2O3 dielectric thin films that are compatible with flexible substrates. In this paper, we first established two non-self-exothermic systems: one with pure aluminum nitrate and one with pure aluminum acetylacetonate. Additionally, we set up one self-exothermic system where aluminum nitrate and aluminum acetylacetonate were mixed in a 1:1 ratio. Tests revealed that the leakage current density and dielectric constant of the self-exothermic system devices were significantly optimized compared to the two non-self-exothermic system devices, indicating that the self-exothermic reaction can effectively improve the quality of the dielectric film. This paper further established two self-exothermic systems with aluminum nitrate and aluminum acetylacetonate mixed in 2:1 and 1:2 ratios, respectively, for comparison. The results indicate that as the proportion of aluminum nitrate increases, the overall dielectric performance of the devices improves. The best overall performance occurs when aluminum nitrate and aluminum acetylacetonate are mixed in a ratio of 2:1: The film surface is smooth without cracks; the surface roughness is 0.747 ± 0.045 nm; the visible light transmittance reaches up to 98%; on the basis of this film, MIM devices were fabricated, with tested leakage current density as low as 1.08 × 10−8 A/cm2 @1 MV and a relative dielectric constant as high as 8.61 ± 0.06, demonstrating excellent electrical performance. [ABSTRACT FROM AUTHOR]

This article aims to explore the most optimal pulsed laser energy density when using the pulsed laser deposition (PLD) process to prepare the MoS2 films. We gradually increased the pulsed laser energy density from 70 mJ·cm−2 to 110 mJ·cm−2 and finally determined that 100 mJ·cm−2 was the best-pulsed laser energy density for MoS2 films by PLD. The surface morphology and crystallization of the MoS2 films prepared under this condition are the best. The films consist of a high-crystallized 2H-MoS2 phase with strong (002) preferential orientation, and their direct optical band gap (Eg) is 1.614 eV. At the same time, the Si/MoS2 heterojunction prepared under the optimal pulsed laser energy density shows an opening voltage of 0.61 V and a rectification ratio of 457.0. [ABSTRACT FROM AUTHOR]