Silicon-based Photodetector Research Articles

High-selectivity NIR amorphous silicon-based plasmonic photodetector at room temperature

This study employed amorphous materials to construct a Near-Infrared (NIR) photodetector, enabling optical sensing over a non-crystalline platform. Utilizing an Au/a-Si Schottky junction with an interfacial oxide layer, the device showcased its capability as a NIR photodetector, effectively operating within a wavelength range of up to 1700 nm. Remarkably, it exhibited significant surface plasmon resonance peaks with high selectivity, a full-width at half-maximum of less than 3°, and a sensitivity of −33.3 dBm, demonstrated at room temperature and zero-biasing conditions. Barrier lowering under biasing further increases the device's responsivity by an order of magnitude, revealing absorption capabilities that exceed the material's intrinsic bandgap limitations. This advancement opens the door to developing highly selective detectors using cost-effective amorphous materials and straightforward design. Additionally, a-Si-based photodetectors contribute to environmental preservation as they do not contain toxic heavy metals, establishing them as one of the most Eco-friendly detection solutions.

A peak enhancement of frequency response of waveguide integrated silicon-based germanium avalanche photodetector

Avalanche photodetectors (APDs) featuring an avalanche multiplication region are vital for reaching high sensitivity and responsivity in optical transceivers. Waveguide-coupled Ge-on-Si separate absorption, charge, and multiplication (SACM) APDs are popular due to their straightforward fabrication process, low optical propagation loss, and high detection sensitivity in optical communications. This paper introduces a lateral SACM Ge-on-Si APD on a silicon-on-insulator (SOI) wafer, featuring a 10 μm-long, 0.5 μm-wide Ge layer at 1310 nm on a standard 8-inch silicon photonics platform. The dark current measures approximately 38.6 μA at −21 V, indicating a breakdown voltage greater than −21 V for the device. The APDs exhibit a unit-gain responsivity of 0.5 A/W at −10 V. At −15 V, their responsivity reaches 2.98 and 2.91 A/W with input powers of −10 and −25 dBm, respectively. The device's 3-dB bandwidth is 15 GHz with an input power of −15 dBm and a gain is 11.68. Experimental results show a peak in impedance at high bias voltages, attributed to inductor and capacitor (LC) circuit resonance, enhancing frequency response. Furthermore, 20 Gbps eye diagrams at −21 V and −9 dBm input power reveal signal to noise ratio (SNRs) of 5.30. This lateral SACM APD, compatible with the stand complementary metal oxide semiconductor (CMOS) process, shows that utilizing the peaking effect at low optical power increases bandwidth.

Two-Step Laser Ablation for the Synthesis of Au:Pb Core/Shell NPs for a High-Performance Silicon-Based Heterojunction Photodetector

In this work, colloidal gold:lead (Au:Pb) core/shell nanoparticles (NPs) were synthesized in liquid at 532 nm using the laser ablation method. An investigation of the external magnetic field during the laser ablation process affected the properties of the Au:Pb NP core and shell. The magnetic field enhances the core shell’s crystallinity. The optical band gap energy increased from 2.067 to 2.086 eV in the presence of the magnetic field. It also led to an increase in the concentration and a decrease in the size of nanoparticles, which led to increased absorbance. A magnetic field strength of 250 mT resulted in a higher removal efficiency. The external magnetic field significantly reduced NP agglomeration and aggregation. We created and characterized an Au:Pb/porous silicon (PS) heterojunction photodetector. The magnetic field greatly enhanced its properties. The responsively (Rλ) of the photodetector increased from 0.093 to 0.551 A/W at λ = 650 nm by increasing the magnetic field. On the other hand, the final Au:Pb/PS material had the best photocurrent stability, demonstrating that adding Au:Pb NPs can make PS's opto-electrical properties more stable. In the end, the Au:Pb NPs/PS heterojunction photodetector results showed that the photodetector parameters got much better when a magnetic field was present. By altering the preparation conditions, we can produce high-performance core/shell photovoltaic devices.

Room-temperature telecom Si:Te PIN planar photodiodes: A study on optimizing device dimensions

The lack of efficient, cost-effective, room-temperature, and silicon-based photodetectors operating at the telecom bands has posed a persistent challenge in the realm of silicon photonics. One potential solution lies in introducing an impurity band within the silicon bandgap, offering a pathway to create a silicon-based photodetector that not only meets the requirements but also benefits from seamless integration with mature CMOS technology. Here, we report on enhancing device performance by introducing geometric modifications while retaining the doping concentration, device area, and operating conditions. The modified devices showcase improved responsivities, reaching approximately 3 × 10−2 A/W at 1300 nm (O band) and 1 × 10−2 A/W at 1500 nm (C band). These values significantly surpass prior work on Si:Te planar photodetectors, demonstrating an improvement of over 30 times. The noise equivalent power however was found to unavoidably increase by one order of magnitude to 10−6 (W /Hz).

Detection performance of flower-like hydrothermally synthesized ZnO in silicon-type photodetector

Zinc oxide (ZnO) is a versatile compound or metal oxide with a wide range of applications across various industries such as electronics, optoelectronics, and gas sensors, etc. A simple hydrothermal method was used to synthesize ZnO flower-like structures in this study. The synthesized ZnO structures were analyzed by x-ray diffractometer (XRD) and scanning electron microscope (SEM). We used ZnO structures as an interfacial layer for a Schottky-type silicon-based photodetector. While Au and Al metals were employed as metallic and ohmic contacts, respectively, p-Si was utilized as a semiconductor and substrate. Thus, Au/ZnO/p-Si sandwich was successfully fabricated and tested by current–voltage (I–V) measurements under dark and various light power illumination densities from 10 mW cm−2 to 150 mW cm−2 as well as the various wavelengths in the case of same power. The I–V characteristics were used to determine the diode and photodetection parameters. The fabricated heterostructure exhibited 77.51 mA W−1 responsivity, 1.30 × 1010 Jones specific detectivity, and 26.33% external quantum efficiency (EQE) values.

Silicon-based planar devices for narrow-band near-infrared photodetection using Tamm plasmons

Abstract Designing efficient narrow-band near-infrared photodetectors integrated on silicon for telecommunications remains a significant challenge in silicon photonics. This paper proposes a novel silicon-based hot-electron photodetector employing Tamm plasmons (Si-based TP-HE PD) for narrow-band near-infrared photodetection. The device combines a one-dimensional photonic crystal (1DPC) structure, an Au layer, and a silicon substrate with a back electrode. Simulation results show that the absorption of the TP device with a back electrode is 1.5 times higher than without a back electrode, due to increased absorption from multiple reflections between the back electrode and the 1DPC structure. Experimentally, the responsivity of the fabricated device reaches 0.195 mA/W at a wavelength of 1400 nm. A phenomenological model was developed to analyze the photoelectric conversion mechanism, revealing reasonable agreement between the theoretically calculated and experimentally measured internal quantum efficiencies. Additional experiments and simulations demonstrate the tunability of the resonance wavelength from 1200 nm to 1700 nm by adjusting structural parameters. The Si-based TP-HE PD shows potential for silicon-based optoelectronic applications, offering the advantages of a simple structure, low cost, and compatibility with silicon photonic integrated circuits. This work represents the first demonstration of a silicon-based hot electron NIR photodetector utilizing Tamm plasmons.

Optical wireless communication using a flexible and waterproof perovskite color converter.

In this Letter, the CH3NH3PbBr3 nanocrystals (NCs) are embedded into the interstices of the fluorine (polyvinyl fluoride/polyvinylidene fluoride, PVF/PVDF) matrix on polyethylene terephthalate (PET) substrate to introduce new advantages, such as being flexible and waterproof, while maintaining the high optical performance of perovskites. The sample's photoluminescence (PL) spectra under 325 nm laser is a green emission peaked at 537 nm with full width at half maximum (FWHM) of about 21.2 nm and a fast PL decay time. As a color converter, it shows high optical absorption and can transform light from solar-blind ultraviolet to a blue region into a green region in air, water, and bending conditions. While excited by a 270 nm ultraviolet light-emitting diode (LED), the system's observed -3 dB bandwidth with the color converter is near 4.4 MHz in air and water conditions with well-eye diagrams at a data rate of 30 Mbps. Finally, we demonstrate an audio transmission application with an ultraviolet light source, a color conversion layer, and a low-cost silicon-based photodetector.

Facilely Fabricated Zero-Bias Silicon-Based Plasmonic Photodetector in the Near-Infrared Region with a Schottky Barrier Properly Controlled by Nanoalloys.

Plasmonic Schottky devices have attracted considerable attention for use in practical applications based on photoelectric conversion, because they enable light to be harvested below the bandgap of semiconductors. In particular, silicon-based (Si) plasmonic Schottky devices have great potential for useful photodetection in the near-infrared region. However, the internal quantum efficiency (IQE) values of previously reported devices are low because the Schottky barrier is excessively high. Here, we are the first to develop AuAg nanoalloy-n-type Si plasmonic Schottky devices by cathodic arc plasma deposition. Interestingly, it is found that a novel nanostructure, which leads to the improvement of responsivities, is formed. Moreover, these plasmonic nanostructures can be fabricated in only ∼1 min. The fabricated AuAg nanoparticle-film structure enables proper control of the Schottky barrier height and increases the area of the Schottky interface for electron transfer. As a result, the considerably enhanced IQE of our device at a telecommunication wavelength of 1310 nm (1550 nm) without external bias is 4.6 (6.5) times higher than those in previous reports, and these responsivities are a record high. This approach can be applied to realize efficient photodetection in the NIR region and extend the use of light below the bandgap of semiconductors. This paves the way for future application advancements in a variety of fields, including photodetection, imaging, photovoltaics, and photochemistry.

Multispectral silicon-based photodetector with stacked PN junctions.

A multispectral silicon-based photodetector structure with stacked PN junctions is proposed in this study. The substrate layer of the proposed photodetector consists of four vertically stacked PN junction structures that contain four photodiodes. The designed structure achieves quantum efficiency of up to 70% and a response time of 5.1 × 10-8 s. The proposed photodetector has a simple structure, and the vertically stacked PN junction structure not only reduces the phenomenon of color aliasing, but also achieves multispectral absorption over the range from ultraviolet to visible light with high response speeds, which provides an effective way to perform high-quality imaging.

High-Responsivity and Broadband MoS2 Photodetector Using Interfacial Engineering.

Combining MoS2 with mature silicon technology is an effective method for preparing high-performance photodetectors. However, the previously studied MoS2/silicon-based heterojunction photodetectors cannot simultaneously demonstrate high responsivity, a fast response time, and broad spectral detection. We constructed a broad spectral n-type MoS2/p-type silicon-based heterojunction photodetector. The SiO2 dielectric layer on the silicon substrate was pretreated with soft plasma to change its thickness and surface state. The pretreated SiO2 dielectric layer and the silicon substrate constitute a multilayer heterostructure with a high carrier concentration and responsiveness. Taking silicon-based and n-type MoS2 heterojunction photodetectors as examples, its responsivity can reach 4.05 × 104 A W1- at 637 nm wavelength with a power density of 2 μW mm-2, and the detectable spectral range is measured from 447 to 1600 nm. This pretreated substrate was proven applicable to other n-type TMDCs, such as MoTe2, ReS2, etc., with certain versatility.

Two-step Laser Ablation in Liquid-assisted Magnetic Fields for Synthesis Au:Pb Core/Shell NPs in Developing High-Performance Silicon-based Heterojunction Photodetector

Two-step Laser Ablation in Liquid-assisted Magnetic Fields for Synthesis Au:Pb Core/Shell NPs in Developing High-Performance Silicon-based Heterojunction Photodetector

Preparation of Graphene Oxide@ZrO2 Core/Shell Nanoparticles by Two-Step Laser Ablation in Liquid Towards a High-Performance Silicon-Based Heterojunction Photodetector

Preparation of Graphene Oxide@ZrO2 Core/Shell Nanoparticles by Two-Step Laser Ablation in Liquid Towards a High-Performance Silicon-Based Heterojunction Photodetector

Achieving a Highly Stable Perovskite Photodetector with a Long Lifetime Fabricated via an All-Vacuum Deposition Process

Hybrid organic-inorganic metal halide perovskites (HOIP) have become a promising visible light sensing material due to their excellent optoelectronic characteristics. Despite the superiority, overcoming the stability issue for commercialization remains a challenge. Herein, an extremely stable photodetector was demonstrated and fabricated with Cs0.06FA0.94Pb(I0.68Br0.32)3 perovskite by an all-vacuum process. The photodetector achieves a current density up to 1.793 × 10-2 A cm-2 under standard one sun solar illumination while maintaining a current density as low as 8.627 × 10-10 A cm-2 at zero bias voltage. The linear dynamic range (LDR) and transient voltage response were found to be comparable to the silicon-based photodetector (Newport 818-SL). Most importantly, the device maintains 95% of the initial performance after 960 h of incessant exposure under one sun solar illumination. The achievements of these outstanding results contributed to the all-vacuum deposition process delivering a film with high stability and good uniformity, which in turn delays the degradation process. The degradation mechanism is further investigated by impedance spectroscopy to reveal the charge dynamics in the photodetector under different exposure times.

Study of collision sensor application for vehicle with high sensitivity silicon-based metal-semiconductor IR photodetector

Study of collision sensor application for vehicle with high sensitivity silicon-based metal-semiconductor IR photodetector

Study of collision sensor application for vehicle with high sensitivity silicon-based metal-semiconductor IR photodetector

In this study used the metal-semiconductor diode as IR photodetector, and through the material, device structural and operation bias selection, high response and fast switching can be achieved. The response can be improved by increasing the doping concentration of the semiconductor material. The doping concentration can be increased by varying the temperature of the semiconductor material, and the device structure can be changed to increase the response speed. The operation bias can be adjusted to produce a higher output signal. The metal-semiconductor diode can be used to detect infrared light and has a relatively low power consumption compared to other infrared photodetectors. The experiment result shown that can reach 1.294 mA/W.

Modeling and Simulation of Si Grating Photodetector Fabricated Using MACE Method for NIR Spectrum

In this research, we modeled a silicon-based photodetector for the NIR-IR spectrum using a grating structure fabricated using the metal-assisted chemical etching method. A nanostructure fabricated by using this method is free of defects such as unwanted sidewall metal depositions. The device is simulated using Lumerical finite difference time domain (FDTD) for optical characteristics and Lumerical CHARGE for electrical characteristics. First, we optimized the grating structure duty cycle parameter for maximum optical power absorption using the particle swarm optimization algorithm provided in Lumerical FDTD, and then used the optimized parameter for our simulations. From Lumerical FDTD simulations, we found that the Cr masker metal used in the fabrication process acts as a resonant cavity and a potential candidate for internal photo emission (IPE) effects. By using Lumerical CHARGE, we performed electrical simulation and by adding the IPE calculation we found that at 850 nm wavelength the Si grating photodetector device exhibited 19 mA/W responsivity and detectivity of 2.62 × 106 Jones for −1 volt operating voltage.

Highly responsive silicon-based hot-electron photodetector with self-aligned metamaterial interdigital electrodes

A sensitive silicon-based hot-electron photodetector based on a self-aligned metal–semiconductor–metal junction is developed. Nearly perfect absorption is achieved with the metamaterial optical coupling, whereas the absorption difference between the upper and lower interdigital gratings is as large as 70% near the resonant wavelength. Arising from the asymmetric photo-absorption, the measured responsivity values of the self-aligned interdigital grating devices reach 1.89 and 0.78 mA/W under zero biasing conditions at the wavelengths of 1310 and 1550 nm, respectively. These values approach the reported record photo-responsivity of hot-electron photodetectors with conventional metal–semiconductor junctions. In addition, the indication of polarity-switchable photocurrent appears due to the wavelength-dependent absorption of the upper and lower metal interdigital gratings. Our device, combining the self-aligned metamaterial interdigital electrodes with highly asymmetric absorption, shows prospects for applications in photodetection, photovoltaics, integrated optoelectronics, and optical communications.

Кремниевые дифференциальные фотоприемники. Технология, характеристики, применение

A silicon-based photodetector containing two identical n+-p photodiodes is described. One of the photodiodes had a wide spectral response with high sensitivity in the ultraviolet region. The sensitivity of the second was reduced in the short-wavelength part of the spectrum by creating additional recombination centers in the near-surface region by implanting As ions. The spectral sensitivity of the differential signal obtained by subtracting photocurrents had a pronounced short-wavelength characteristic. The long-wavelength limit of the spectral range in terms of the λ0.5 level, depending on the doping dose, was in the range of 0.37 — 0.47 μm. The sensitivity maximum corresponded to λmax=0.32 — 0.37 μm. The electrical and noise characteristics of the photodetector are given. The possibility of using differential photodetectors as two-color ones is shown.

A high-performance broadband double-junction photodetector based on silicon nanowire arrays wrapped by silver nanoparticles for low-light imaging

An NN+/MS double-junction nanowire silicon-based photodetector was fabricated, which exhibits excellent high-sensitivity, ultralow dark current, and broadband detection performances.

Zinc-hyperdoped silicon photodetectors fabricated by femtosecond laser with sub-bandgap photoresponse

Developing a low-cost, room-temperature operated and complementary metal-oxide-semiconductor (CMOS) compatible near infrared silicon photodetector is of interest for creating all-silicon optoelectronic integrated circuits. However, a silicon-based photodetector usually cannot respond to infrared light with wavelengths longer than 1100 nm, due to the bandgap (1.12 eV) limitation of silicon. Here, we present a zinc-hyperdoped silicon (Si:Zn)-based photodetector that exhibits an enhanced sub-bandgap photoresponse. The Si:Zn shows a broadband infrared absorption over 50%, with a zinc concentration reaches 4.66 × 1019 cm−3 near the surface. The responsivity of the Si:Zn photodetector reaches 0.68 mAW−1 at 1550 nm, −1 V bias, with a rise and fall time of 0.560 ms and 0.445 ms, respectively. The Si:Zn has the potential for a wide range of applications in various fields due to its combination of low cost, CMOS compatibility, and room-temperature operating conditions.