查找使用阿拉丁产品的科研文献

Enhanced performance of solar-blind UV detectors based on Ti3C2Tx/AlGaN heterojunction

Yü Jingzhao,Zhang Yuqing,Wang Liying,Yang Xijia,Yang Yue,Jiang Ke,Lü Wei,Sun Xiaojuan

AlGaN is an ideal material for fabricating ultraviolet (UV) photodetectors targeting the solar-blind wavelength range. However, the performance of UV detectors based on AlGaN is still limited by its material quality and effective p-type doping. Herein, we propose an external modulation method by combining AlGaN with two-dimensional MXene (Ti 3 C 2 T x ) to construct Ti 3 C 2 T x /AlGaN heterostructures. It has been shown that Ti 3 C 2 T x undergoes a transition from a metallic material to a semiconductor depending on oxidation, and the performance of Ti 3 C 2 T x /AlGaN detectors could be adjusted accordingly. The effect of oxidation process of Ti 3 C 2 Tx on performance of Ti 3 C 2 T x /AlGaN photodetectors has been investigated systematically. The optimized devices exhibited a rise time of 72 ms and a decay time 30 ms, achieving a responsivity of 3000 mA/W under 270 nm UV light irradiation.

A differential extended gate-AlGaN/GaN HEMT sensor for real-time detection of ionic pollutants

Lei Zhao,Xinsheng Liu,Bin Miao,Zhiqi Gu,Jin Wang,HuoXiang Peng,Jian Zhang,Bin Zeng,Jiadong Li

In this study, we propose a differential extended gate (DEG)-AlGaN/GaN high electron mobility transistor (HEMT) sensor to detect ionic pollutants in solution. The DEG-AlGaN/GaN HEMT sensor consists of two extended gate sensing units, which combine the differential method with the extended gate structure. Ionic pollutant Fe3+ is used to test the feasibility of the device. Compared to the conventional AlGaN/GaN HEMT sensor, DEG-AlGaN/GaN HEMT sensors can effectively reduce the effect of noise factors and successfully improve the detection limit to 10 fM. At the same time, the DEG sensor shows that Fe3+ can be detected in a wide range of concentrations, varying from 10 fM to 100 μM, and it shows better linearity (R2 = 0.9955) than the conventional AlGaN/GaN HEMT sensor. These results demonstrate that the unique DEG design can overcome the drawbacks of the conventional AlGaN/GaN HEMT sensor, and significantly improve the overall performance of the AlGaN/GaN HEMT sensor. As a result, this novel sensor has the potential to be a real-time and high-performance test tool for environmental monitoring.

A highly sensitive sensor for carcinoembryonic antigen based on AlGaN/GaN high-electron-mobility transistors

WeiSun Huang,Shengjie Hu,Xuecheng Jiang,Yuyan Weng,Yu Liu,Xue Tang,Guofeng Yang,Xun Wang,Naiyan Lu

Carcinoembryonic antigen (CEA) is a well-known biomarker and validated serum biomarker for lung cancer. We introduce a simple label-free method for CEA detection. Specific recognition of CEA was made possible by immobilizing CEA antibodies in the sensing region of AlGaN/GaN high-electron-mobility transistors. The biosensors have a detection limit of 1 fg ml−1 in phosphate buffer solution. This approach has advantages of integration, miniaturization, low cost, and rapid detection compared to other testing methods for lung cancer and could be used in future medical diagnostics.

Integrated Electronic Tags based Vertical Flow Assay (e-VFA) with Micro-sieve and AlGaN/GaN HEMT sensors for Multi-target detection in Actual Saliva

Zhiqi Gu,Hui Chang,Guo Yang,Boxuan Xu,Bin Miao,Jiadong Li

Vertical flow assay (VFA) is an effective point-of-care (POC) diagnostic tool for widespread applications. Nevertheless, the lack of multi-target detection and multi-signal readout capability still remain challenges. Herein, a brand new VFA scheme for multi-target saliva detection based on electronic-tags was proposed, where AlGaN/GaN HEMT sensors modified with different bio-receptors as electronic tags endowed the VFA a multi-target detection capability. In addition, the use of electronic tags instead of optical tags made that the VFA could simultaneously carry out direct multi-target readout, which ensure the effective POC diagnostic of saliva analysis. Moreover, by integrating a hydrophilically optimized micro-sieve, impurities like sticky filaments, epidermal cells and other large-scale charged particles in saliva were effectively screened, which enabled the direct detection of saliva by AlGaN/GaN HEMT sensors. Glucose, urea, and cortisol were selected to verified the feasibility of the multi-target e-VFA scheme, results displayed that the limit-of-detection (LOD) was as low as 100 aM. The linear response was demonstrated in the dynamic range of 100 aM - 100 μM, the specificity and long-term stability and the validity of the actual saliva test were also verified. These results demonstrated that the as-proposed e-VFA had potential application in saliva detection for multi-target simultaneous detection, and it is expected to achieve the real-time detection of more biological targets in saliva.

A Salivary Urea Sensor Based on Microsieve Disposable Gate AlGaN/GaN High Electron Mobility Transistor

Guo Yang,Boxuan Xu,Hui Chang,Zhiqi Gu,Jiadong Li

The abundant bio-markers in saliva provide a new option for non-invasive testing. However, due to the presence of impurities in the saliva backgroud, most of the existing saliva testing methods rely on pre-processing, which limits the application of saliva testing as a convenient means of testing in daily life. Herein, a disposible-gate AlGaN/GaN high electron mobility transistor (HEMT) biosensor integrated with micro-sieve was intoduced to solve the problem that signal interference caused by charged impurities in saliva for HEMT based biosensors, where the micro-sieve was ultilized as a pre-treatment unit to remove large particles of impurities from saliva through size effect and thus greatly inproving the accuracy of detection. The experimental results showed that the HEMT based biosensor has has excellent linearity (R2 = 0.9977) and a high sensitivity of 6.552 µA·dec−1 for urea sensing from 1 fM to 100 mM in 0.1×PBS solution. When it comes to artificial saliva detection, compare to the HEMT sensor without micro-sieve (sensitivity = 3.07432μA·dec−1), the sensitivity of HEMT sensor integrated with micro-sieve had almost no change. Moreover, to verify that urea can be detected in actual saliva, urea is sensed directly in human saliva. The addition of the microsieve module provides a new way for biosensors to detect specific markers in saliva in real time, and the designed HEMT biosensor with microsieve function has a wide range of application potential in rapid saliva detection.

Highly sensitive AlGaN/GaN HEMT biosensors using an ethanolamine modification strategy for bioassay applications

Zhiqi Gu,Jin Wang,Bin Miao,Lei Zhao,Xinsheng Liu,Dongmin Wu,Jiadong Li

In this paper, we propose a highly efficient surface modification strategy on an AlGaN/GaN high electron mobility transistor (HEMT), where ethanolamine (EA) was utilized to functionalize the surface of GaN and provided amphoteric amine groups for probe molecular immobilization for bioassay application. The molecular gated-AlGaN/GaN HEMT was utilized for pH and prostate-specific antigen (PSA) detection to verify its performance as a biosensor. Benefitting from the high coating quality on the GaN surface, the performance of our biosensor is drastically improved compared to other AlGaN/GaN HEMT based pH and PSA biosensors reported before. Our molecular gated-AlGaN/GaN HEMT biosensor has achieved good static electrical performance for pH sensing, such as high sensitivity, good linearity and chemical stability. Moreover, after further immobilization of PSA antibody onto the EA aminated GaN surface, the limit of detection (LOD) for PSA detection is as low as 1 fg mL−1 in PBS buffer, which has reached an at least two orders of magnitude decrease compared to any other AlGaN/GaN HEMT based PSA biosensor reported before. And the sensitivity of our PSA biosensor has achieved a substantial increase, reaching up to 2.04% for 100 ng mL−1. The measurements of pH and PSA utilizing the EA modified AlGaN/GaN HEMT biosensor indicate that the surface modification strategy on the GaN proposed in this paper can effectively improve the performance of the AlGaN/GaN HEMT based biosensor, which demonstrates a promising application prospect in the AlGaN/GaN HEMT based biological detection field.

Ultrahigh-Responsivity Ultraviolet Phototransistor Enabled by Ferroelectric Gating Enhancement Based on an AlGaN/GaN HEMT

Lisheng Chen,Xiannian Shi,Zhixin Lin,Jiao Xu,Teng Yun,Sudong Wu

The development of high-performance ultraviolet (UV) photodetectors is often constrained by a fundamental tradeoff between responsivity, response speed, and power consumption, limiting their overall performance. Here, we demonstrate a device paradigm that addresses this challenge by integrating a Bi ${}_{{3}.{25}}$ La ${}_{{0}.{75}}$ Ti₃O₁₂ (BLT) ferroelectric gate dielectric with an AlGaN/GaN high-electron-mobility transistor (HEMT). The design leverages a nonvolatile polarization field of the ferroelectric material in tandem with an external electric field to modulate the 2-D electron gas (2DEG) channel, offering a unique mechanism for fine-tuning optoelectronic performance. Benefiting from this ferroelectric gating enhancement, the BLT-gated phototransistor exhibits outstanding and well-balanced characteristics, including an ultrahigh responsivity of $2.13\times 10^{{6}}$ A/W, a specific detectivity of $9.36\times 10^{{14}}$ Jones, and rise/fall times of 0.38/2.84 s. The device can also detect weak UV light at 360nm with an illumination intensity as low as $2~\mu $ W/cm². This work demonstrates a novel approach for electrically tuning responsivity via ferroelectric poling, offering a promising pathway toward high-performance UV phototransistors. These findings advance the design of UV photodetectors with balanced performance for a wide range of practical optoelectronic applications.

Tunable structured AlGaN-based nanoporous distributed Bragg reflectors for light-coupling enhancement in monolayer MoS2

Shizhou Tan,Pengcheng Jian,Maocheng Shan,Yongming Zhao,Zhihua Zheng,Yiming Yang,Yuhui Zeng,Dan Xu,Zhenyu Chen,Changqing Chen,Feng Wu,Jiangnan Dai

In this work, we demonstrated tunable structured AlGaN-based nanoporous (NP) distributed Bragg reflectors (DBRs) with high-reflectivity through one-step vertical-lateral electrochemical etching (ECE). The aperture of nanopores in the doping layer and the size and density of V-pits on the surface of NP-DBRs can be tuned by controlling the etching bias. Furthermore, by further tuning the thickness of alternating layers, we achieved high reflectivity of NP-DBRs at multiple center wavelengths within the wavelength range from 280 to 800 nm. To explore its potential applications, MoS 2 with a photoluminescence (PL) emission in the red light region was grown for the first time on the NP-DBRs. Due to the light localized effect of surface V-pits and the high reflectivity of the bottom DBRs , the PL intensity of MoS 2 was significantly enhanced by a factor of 37.3 compared to the region without NP-DBRs. The PL enhancement of MoS 2 on porous AlGaN and different periodic NP-DBRs further validated the PL enhancement mechanism. The corresponding theoretical simulations also revealed that the PL enhancement should be attributed to the combined effect of enhanced light absorption and NP-DBRs induced emission interference. The fabricated AlGaN-based NP-DBRs provide a new approach for improving the quantum efficiency of two-dimensional layered materials, which holds significant importance for advancing the development of miniaturized and integrated 2D/3D heterogeneous structure systems in the field of optoelectronics.

An AuNPs-functionalized AlGaN/GaN high electron mobility transistor sensor for ultrasensitive detection of TNT

Yahui Guo,Xiongtao Wang,Bin Miao,Ying Li,Weirong Yao,Yunfei Xie,Jiadong Li,Dongmin Wu,Renjun Pei

Herein, an ultrasensitive sensor based on a AlGaN/GaN high electron mobility transistor (HEMT) was developed for the detection of 2,4,6-trinitrotoluene (TNT). The sensing surface of the AlGaN/GaN HEMT grid was covalently bonded with a layer of gold nanoparticles which were functionalized with cysteamine for specific electrostatic interaction with TNT. The binding of TNT to cysteamine through donor–acceptor interactions could affect the surface charge on the gate area of the AlGaN/GaN HEMT, resulting in a gate voltage change and density changes of the 2-dimensional electron gas (2EDG) at the interface of AlGaN/GaN. By the merit of the high electron mobility of the AlGaN/GaN transistor and robust binding between cysteamine and TNT, the sensor demonstrated a fast response and excellent performance with quantitative ranges at ppt levels (from 0.1 ppt to 10 ppb) with good selectivity towards TNT. This HEMT sensor showed attractive properties for TNT detection in terms of speed, sensitivity and miniaturization.

Ethanolamine Modified ZnO Nanorods-Based Disposable Gate-AlGaN/GaN High Electron Mobility Transistor for pH Sensing

Zhiqi Gu,Jin Wang,Bin Miao,Xinsheng Liu,Lei Zhao,Huoxiang Peng,Dongmin Wu,Jiadong Li

Electrical detection of trace zinc ions with an extended gate-AlGaN/GaN high electron mobility sensor

Le Gu,Shuai Yang,Bin Miao,Zhiqi Gu,Jin Wang,Wei Sun,Dongmin Wu,Jiadong Li

In this report, we have developed a high sensitivity zinc ion (Zn2+) detection method based on a Schiff base functionalized extended gate (EG)-AlGaN/GaN high electron mobility (HEMT) sensor. The complexation reaction between the Schiff base and the zinc ions would cause surface potential change on the extended gate, and achieve the purpose of zinc ion detection. Compared with conventional methods, the Schiff base functionalized EG-AlGaN/GaN high electron mobility sensor showed a rapid response (less than 10 seconds) and the limit of detection (LOD) was 1 fM. At the same time, the real-time detection of zinc ion concentration ranging from 1 fM to 1 μM showed good linearity (R2 = 0.9962). These results indicated that it provides a promising real-time detection method for trace-free zinc ion trace detection.

A Miniature Biomedical Sensor for Rapid Detection of Schistosoma japonicum Antibodies

Shengjie Hu,Xuecheng Jiang,Liang Yang,Xue Tang,Guofeng Yang,Yuanyuan Hu,Jie Wang,Naiyan Lu

Schistosomiasis, typically characterized by chronic infection in endemic regions, has the potential to affect liver tissue and pose a serious threat to human health. Detecting and screening for this disease early on is crucial for its prevention and control. However, existing methods encounter challenges such as low sensitivity, time-consuming processes, and complex sample handling. To address these challenges, we report a soluble egg antigen (SEA)-based functionalized gridless and meander-type AlGaN/GaN high electron mobility transistors (HEMT) sensor for the highly sensitive detection of antibodies toSchistosoma japonicum. Immobilization of the self-assembled membrane on the gate surface was verified using a semiconductor parameter analyzer, scanning electron microscope (SEM), and atomic force microscopy (AFM). The developed biosensor demonstrates remarkable performance in detecting anti-SEA, exhibiting a linear concentration range of 10 ng/mL to 100 μg/mL and a sensitivity of 0.058 mA/log (ng/mL). It also exhibits similar excellent performance in serum systems. With advantages such as rapid detection, high sensitivity, miniaturization, and label-free operation, this biosensor can fulfill the requirements for blood defense.Keywords:biomedical sensor;AlGaN/GaN high electron mobility transistors (HEMT);Schistosoma japonicum;soluble egg antigens (SEA);rapid detection