High-performance Photodetectors Research Articles

Multi-Resonance 1,4-BN-Heteroarene for Filterless Narrowband Photodetector.

As an emerging class of optoelectronic materials, multi-resonance (MR) 1,4-BN-heteroarenes have been extensively employed as narrowband electroluminescence materials, whereas their absorption feature has largely been neglected. Here we construct the first MR-molecule-based phototransistor for filterless narrowband photodetectors (NBPDs) by anchoring narrowband absorption MR molecules on the high-mobility semiconductor indium-zinc-oxide (IZO) film. The resulting device exhibits high-performance photodetection with a small full-width at half-maximum (FWHM) of 33 nm, which represents a new record for NBPDs based on intrinsic narrowband absorbing materials. These results demonstrate the great potential of MR materials as a new molecular platform for developing high-performance NBPDs.

Solvent-modulated preparation of lead-free Cs3Bi2I9polycrystalline film for high-performance photodetectors.

Lead-free cesium bismuth iodide (Cs3Bi2I9) perovskite exhibits extraordinary optoelectronic properties and attractive potential in various optoelectronic devices, especially the application for photodetectors. However, most Cs3Bi2I9photodetectors demonstrated poor detection performance due to the difficulty in obtaining high-quality polycrystalline films. Therefore, it makes sense to modulate the preparation of high-quality Cs3Bi2I9polycrystalline films and expand its applications. Here, a solvent-modulated method combining anti-solvent and precursor engineering has been developed to regulate the crystallization dynamics of Cs3Bi2I9. Anti-solvent treatment is to suppress the asynchronous separation out of CsI and BiI3due to significant differences in solubility, promoting uniform nucleation and limiting flake-like growth. Precursor engineering is synchronously used to modulate the subsequent nucleation growth dynamics. Due to the synergistic modulation, smooth and compact Cs3Bi2I9polycrystalline films with distinct grains and grain boundaries can be easily obtained. The as-prepared photodetector exhibits an excellent on/off ratio of 4.26×105as well as the detectivity up to 6.49×1010Jones at zero bias. And, the Cs3Bi2I9photodetector indicates excellent device stability, maintaining about 70% of the original performance after being stored for 400 hours in the air without encapsulation.&#xD.

High-Performance Ultraviolet Photodetector Based on the Vertical GaSe/GaN Heterojunction.

Ultravioletlight detection is essential for environmental monitoring, hazard alerting, and optical communication. Here,a vertical UV photodetector is proposed and demonstrated by stacking the freestanding GaN-film on the 2DGaSe flake. Benefits from the vertical heterostructure and built-in electric field, the photodetector exhibits excellent photoresponse properties, including a high responsivity of 1.38 × 105 A/W and a high specific detectivity of 1.40 × 1016 Jones under 362nm wavelength illumination. Additionally, the device demonstrates fast rise and decay time of 18.0 and 21.8 µs, respectively. This work paves the way for design and realization of the high-performance GaN-based photodetectors.

Te2-Regulated Black Arsenic Phosphorus Monocrystalline Film with Excellent Uniformity for High Performance Photodetection.

Two-dimensional (2D) black arsenic phosphorus (b-AsP) material has been attracting considerable attention for its extraordinary properties. However, its application in large-scale device fabrication remains challenging due to the limited scale and irregular shape. Here, we found the special effect of Te2 upon growth of b-AsP and developed a novel Te2-regulated steady growth (Te-SG) strategy to obtain high-quality b-AsP single crystal. The large-scale b-AsP single crystal sheet with its full width at half-maximum (FWHM) being ≤0.05° was achieved for the first time. The b-AsP monocrystalline film with atomic-level flat surface was further fabricated by laser, which exhibits outstanding self-powered characteristics under various light illumination, including low dark current and peak room-temperature detectivity of 8.5 × 1010 cm Hz1/2 W-1. The excellent uniformity was also revealed through a large-plane b-AsP photodetector. This work paves a new way for the application of high-performance electronics and optoelectronics based on b-AsP.

Gate-tunable photodetectors based on MoTe2/MoS2heterostructures anti-ambipolar transistors.

Anti-ambipolar transistors (AAT) are considered as a breakthrough technology in the field of electronics and optoelectronics, which is not only widely used in diverse logic circuits, but also crucial for the realization of high-performance photodetectors. The anti-ambipolar characteristics arising from the gate-tunable energy band structure can produce high-performance photodetection at different gate voltages. As a result, this places higher demands on the parametric driving range (ΔVg) and peak-to-valley ratio (PVR) of the AAT. Here, we demonstrate a high-performance photodetector with anti-ambipolar properties based on a van der Waals heterojunction of MoTe2/MoS2. Flexible modulation of carrier concentration and transport by gate voltage achieves a driving voltage range ΔVg as high as 38.4 V and a peak-to-valley ratio PVR of 1.6 × 102. Most importantly, MoTe2/MoS2 exhibits a pronounced gate-tunable photoresponse, which is attributed to the modulation of photogenerated carrier transport by gate voltage. The MoTe2/MoS2 heterojunction photodetector exhibits excellent performance, including an impressive responsivity of 17 A/W, a high detectivity of 4.2 × 1011 cm Hz1/2 W-1, an elevated external quantum efficiency of 4 × 103 %, and a fast response time of 21 ms. Gate-tunable photodetectors based on MoTe2/MoS2 heterostructures AAT have potential to realize optoelectronic devices with high performance, providing a novel strategy to achieve high-performance photodetection.

High-performance broadband photodetectors based on MnSe/SnS2 heterojunction

Abstract Two-dimensional (2D) materials have emerged as promising candidates for broadband photodetectors due to their unique optoelectronic properties. However, intrinsic defects and limited spectral response hinder their practical applications. In this study, we developed a novel 2D heterojunction photodetector by combining non-layered p-type MnSe nanosheets with layered n-type SnS2 flakes. The MnSe nanosheets were synthesized using chemical vapor deposition, while the SnS2 flakes were obtained through mechanical exfoliation. The fabricated MnSe/SnS2 heterojunction device exhibited rectifying behavior with an impressive on/off current ratio over 5000. Remarkably, the photodetector demonstrated a broad spectral response ranging from ultraviolet to near-infrared (405–1060 nm), achieving an exceptionally high responsivity of 10 A W−1, a detectivity of 3.06 × 1010 Jones, and an external quantum efficiency of 3068%. The enhanced performance was attributed to the type-II band alignment and built-in potential of the heterojunction, which facilitated effective separation of photogenerated carriers. Furthermore, the device exhibited significant photovoltaic characteristics, enabling self-powered imaging in visible range. This study highlights the potential of 2D non-layered materials in combination with traditional 2D layered materials for the development of high-performance, broadband photodetectors with improved efficiency and self-powered capabilities.

Two-Dimensional Phototransistors with van der Waals Superstructure Contacts for High-Performance Photosensing.

Semiconducting transition metal dichalcogenides (TMDs) possess exceptional photoelectronic properties, rendering them excellent channel materials for phototransistors and holding great promise for future optoelectronics. However, the attainment of high-performance photodetection has been impeded by challenges pertaining to electrical contact. To surmount this obstacle, we introduce a phototransistor architecture, in which the WS2 channel is connected with an alternating WS2-WSe2 strip superstructure, strategically positioned alongside the source and drain contact regions. Illumination triggers efficient separation of photoexcited electrons and holes due to the type-II staggered band alignment within the superstructure. Consequently, the contact regions exhibit degenerately doped n+ WS2 and p+ WSe2 strips under light illumination, resulting in minimal contact resistivity with the metal electrodes. The resultant WS2 phototransistor exhibits a remarkable responsivity of 2.4 × 106 mA/W and an impressive detectivity of 2.6 × 1012 Jones. Furthermore, our time-resolved measurements reveal the absence of persistent photoconductance. This proposed phototransistor architecture provides a route for high-performance photodetection, effectively surpassing previous limitations associated with electrical contact.

Unraveling the thickness-dependent high photoconductivity in BaSnO3 thin films: insights from ultrafast charge carrier dynamics

Abstract Barium stannate, a perovskite-structured semiconductor, is gaining significant attention for its potential in high-performance UV photodetectors and optoelectronic applications. This study investigated the photo-response of epitaxial BaSnO3 (BSO) thin films grown using pulsed laser deposition. Our findings revealed an exceptionally high photo-response in BSO films having thicknesses (90, 270, and 360 nm). Detailed optical analyses were conducted to elucidate the photoconductive response’s mechanisms, including photoluminescence (PL), time-resolved PL, and the ultrafast transient spectroscopy. Notably, ultrafast transient spectroscopy was employed for the first time on this material. Leveraging BSO’s wide bandgap (3.4 eV), photoconductivity measurements in the UV range showed a peak responsivity of 5 A W−1 at 5 V with a 360 nm film and a response time of 470 ms. The transient spectroscopy reveals the thickness-dependent carrier dynamics, such as carrier relaxation, carrier trapping in mid-gap states, and recombination. Specifically, observed trapping times were approximately 6 ps for 360 nm thickness, 26 ps for 270 nm thickness, and 59 ps for 90 nm thickness of BSO thin film. This research enhances the understanding of the photoconductive behavior of barium stannate thin films and lays the groundwork for optimizing BSO-based UV-sensitive optoelectronic devices.

High-performance solar-blind ultraviolet photodetector arrays based on two-inch ϵ-Ga2O3 films for imaging applications

Abstract To achieve high-quality solar-blind imaging applications based on ultrawide bandgap semiconductor photodetectors, it is crucial to fabricate highly uniform wafer-scale films. In this work, we demonstrate the fabrication of exceptionally uniform two-inch ε-Ga2O3 thin films on sapphire substrates using an off-axis pulsed laser deposition method. The two-inch ε-Ga2O3 films exhibit remarkable uniformity across key parameters, including thickness, crystalline quality, bandgap, and surface roughness, with an inhomogeneity ratio less than 5%. Additionally, these films are preferentially oriented along the (001) crystal plane. At 20 V bias, the individual ε-Ga2O3 photodetector demonstrates outstanding solar-blind ultraviolet (UV) photodetection performance, with a responsivity of 52.77 A/W at 240 nm, an external quantum efficiency of 2.7×104%, a dark current of 5.5×10-11 A and a UV–visible rejection ratio of 1.2×104. Furthermore, the 10×10 photodetector arrays fabricated on two-inch ε-Ga2O3 films exhibit highly uniform photodetection performance, with photocurrent deviations remaining within one order of magnitude and a maximum standard deviation of ~8%. High-contrast optical imaging of the letters of “NIMTE” is successfully achieved using the 10×10 photodetector array detector. This work provides valuable insights for fabricating wafer-scale uniform ε-Ga2O3 films and achieving high-quality solar-blind UV imaging applications.

Nonpolar P-type Conjugated Small Molecules Enable High-Performance Organic Photodetectors for Potential Application in Optical Wireless Communication.

The high responsivity and broad spectral sensitivity of organic photodetectors (OPDs) present a bright future of commercialization. However, the relatively high dark current density still limits its development. Herein, two novel nonpolar p-type conjugated small molecules, NSN and NSSN, are synthesized as interface layers to enhance the performance of the OPDs, which not only can tune energy alignments and increase the reverse charge injection barrier but also can reduce the interfacial trap density. Moreover, benefiting from the smoother surface morphology and enhanced conductivity, the NSN exhibited superior charge transport and collection properties. Consequently, the OPD with NSN achieved a dark current density of 0.37 nA cm-2 and a high specific detectivity of 2.77 × 1013 Jones at -2 V. More importantly, the optimized OPDs can be successfully integrated into optical communication systems, demonstrating precise digital signal communication without obvious distortion, showing promising application potential in the wireless transmission system.

High-Performance Solar-Blind Ultraviolet Photodetectors Based on a Ni/β-Ga2O3 Vertical Schottky Barrier Diode.

Ga2O3 Schottky photodiodes are being actively explored for solar-blind ultraviolet (SBUV) detection, owing to the fast photoresponse and easy fabrication. However, their performance, limited by the Schottky contact, mostly underperforms the expectations. Herein, a Ni/β-Ga2O3 vertical Schottky barrier diode (SBD) with an ultrathin anode electrode is demonstrated. Through simple surface treatment, the quality of the Schottky junction is improved, thus the detection performance. The dark current reaches a record of less than 12 fA. Benefiting from this, an ultrahigh photo-to-dark current ratio (PDCR) of 4.92 × 107 and specific detectivity D* of 2.76 × 1015 Jones are achieved. The response time is also reduced to the order of milliseconds. The experimental result shows that the device still works properly at a high temperature of 150 °C. Most importantly, the fabricated photodetectors have good uniformity and operational stability. Our results provide a simple approach to mass produce high-performance Ga2O3 photodetectors, holding tremendous potential for UV imaging applications.

High-performance broad-spectrum self-powering photoelectrochemical photodetectors based on MnPSe3 nanosheets

Transition metal phosphorus trichalcogenides (MPX3), as a group of layered van der Waals materials with wide tunable bandgaps, high carrier mobility and good light absorption, are potential candidates for the preparation of high-performance broad-spectrum photoelectrochemical photodetectors (PEC PDs). MnPSe3, a p-type semiconducting material in the MPX3 family, was exfoliated into nanosheets using liquid-phase exfoliation, and then applied in the PEC PDs. The MnPSe3-based PEC PDs were thoroughly investigated in a three-electrode system and demonstrated self-powered photoelectric performance across a broad spectral range of 400-800nm. Specifically, under 400nm illumination, the photodetector showed the optimal performance with a photocurrent density of 9.72 μA/cm2, responsivity of 85.55 μA/W, response times of 10/15 ms and fine cyclic stability under the biased condition. In addition, effects of different stripping agents, bias voltages, wavelengths and optical powers on the device performance were compared. These findings suggest that MnPSe3 is a highly promising material in applications of high-performance self-powered PEC PDs.

High-performance ultrafast broadband photodetector based on van der Waals heterojunction through oxygen defect engineering

High-performance ultrafast broadband photodetector based on van der Waals heterojunction through oxygen defect engineering

High-performance self-powered NIR photodetectors enabled by PbSe quantum dot surface passivation with P3HT through bulk-heterojunction integration

High-performance self-powered NIR photodetectors enabled by PbSe quantum dot surface passivation with P3HT through bulk-heterojunction integration

Flexible silicon for high-performance photovoltaics, photodetectors and bio-interfaced electronics.

Silicon (Si) is currently the most mature and reliable semiconductor material in the industry, playing a pivotal role in the development of modern microelectronics, renewable energy, and bio-electronic technologies. In recent years, widespread research attention has been devoted to the development of advanced flexible electronics, photovoltaics, and bio-interfaced sensors/detectors, boosting their emerging applications in distributed energy sources, healthcare, environmental monitoring, and brain-computer interfaces (BCIs). Despite the rigid and brittle nature of Si, a series of new fabrication technologies and integration strategies have been developed to enable a wide range of c-Si-based high-performance flexible photovoltaics and electronics, which were previously only achievable with intrinsically soft organic and polymer semiconductors. More interestingly, programmable geometric engineering of crystalline silicon (c-Si) units and logic circuits has been explored to enable the fabrication of various highly flexible nanoprobes for intracellular sensing and the deployment of soft BCI matrices to record and understand brain neural activities for the development of advanced neuroprosthetics. This review will systematically examine the latest progress in the fabrication of Si-based flexible solar cells, photodetectors, and biological probing interfaces over the past decade, identifying key design principles, mechanisms, and technological milestones achieved through novel geometry, morphology, and composition control. These advancements, when combined, will not only promote the practical applications of sustainable energy and wearable electronics but also spur new breakthroughs in emerging human-machine interfaces (HMIs) and artificial intelligence applications, which hold significant implications for understanding neural activities, implementing more efficient artificial Intelligence (AI) algorithms, and developing new therapies or treatments. Finally, we will summarize and provide an outlook on the current challenges and future opportunities of Si-based electronics, flexible optoelectronics, and bio-sensing.

High-performance ZnO nanorod arrays UV photodetectors enabled by biosynthetic pyomelanin as carrier transport layers

High-performance ZnO nanorod arrays UV photodetectors enabled by biosynthetic pyomelanin as carrier transport layers

Fabrication of high-performance UV photodetector using Gallium doped ZnO thin films by Nebulizer Spray Pyrolysis method.

Fabrication of high-performance UV photodetector using Gallium doped ZnO thin films by Nebulizer Spray Pyrolysis method.

Dual strategy of interface and absorber modifications via Ti3C2Tx MXene for high-performance self-powered CsPbCl3 UV photodetectors

Dual strategy of interface and absorber modifications via Ti3C2Tx MXene for high-performance self-powered CsPbCl3 UV photodetectors

Enhanced response of an infrared photodetector based on hybridization between reduced graphene oxide and up-conversion microparticles.

Infrared (IR) photodetectors play an important role in many fields such as industry, medicine, security, etc. Achieving high response and maintaining stability in the device performance while reducing materials cost are required for the practical use of optical sensors. This study presents the development of a low-cost but high-performance IR photodetector based on a hybridization of up-conversion microparticles of NaYF4:Tm,Yb (UCMPs) and reduced graphene oxide material (RGO). In this combination, UCMPs play the role of absorbing photons from 980 nm excitation light, generating electron-hole pairs, which are useful for sensing applications. Meanwhile, RGO acts as a charge collector or a charge transport layer because of its high mobility, good electro-conductivity, and large surface area. Through various characterization experiments in dark and light conditions, the analysis results confirm that our devices show sensitivity to IR light with excellent operation stability up to 30 days even stored in ambient conditions. Overall, the combination of UCMPs and RGO materials promises to increase the ability to absorb infrared light, the optical sensitivity of the photodetector.

Preparation of High-performance UV Photodetectors Based on Growing ZnO Nanowires via Focused Ion Beam Exposure

Preparation of High-performance UV Photodetectors Based on Growing ZnO Nanowires via Focused Ion Beam Exposure