A5068605344- Advanced Optical Sensing Technologies
- Advanced Semiconductor Detectors and Materials
- Semiconductor Quantum Structures and Devices
- Photonic and Optical Devices
- Semiconductor Lasers and Optical Devices
- CCD and CMOS Imaging Sensors
- Semiconductor materials and interfaces
- Integrated Circuits and Semiconductor Failure Analysis
- Ocular and Laser Science Research
- Optical Imaging and Spectroscopy Techniques
- Semiconductor materials and devices
- Molecular Junctions and Nanostructures
- Near-Field Optical Microscopy
- Freezing and Crystallization Processes
- Metallurgical and Alloy Processes
- Infrared Target Detection Methodologies
- Rare-earth and actinide compounds
- Organic Light-Emitting Diodes Research
- Color Science and Applications
- Advanced MEMS and NEMS Technologies
- Advancements in Semiconductor Devices and Circuit Design
- Spectroscopy and Laser Applications
- GaN-based semiconductor devices and materials
- Photocathodes and Microchannel Plates
- Magnetic Properties of Alloys
University of Sheffield
2012-2024
Photonics (United States)
2024
Shandong University of Science and Technology
2018
Jingchu University of Technology
2017
California Polytechnic State University
2007-2012
Academia Sinica
1992
High sensitivity avalanche photodiodes (APDs) operating at eye-safe infrared wavelengths (1400–1650 nm) are essential components in many communications and sensing systems. We report the demonstration of a room temperature, ultrahigh gain ( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"> <mml:mi>M</mml:mi> <mml:mo>=</mml:mo> <mml:mrow class="MJX-TeXAtom-ORD"> <mml:mn>278</mml:mn> </mml:mrow> </mml:math> , <mml:mi>λ</mml:mi> <mml:mn>1550</mml:mn> <mml:mspace...
Low noise avalanche photodiodes (APDs) detecting 1550 nm wavelength play a crucial role in optical communication and LiDAR systems. These APDs utilize separate absorption, charge, multiplication (SACM) architecture with an absorber for 1400–1650 detection low noise, high gain multiplier that can be independently optimized signal-to-noise ratio. Recently, GaAs0.5Sb0.5/Al0.85Ga0.15As0.56Sb0.44 SACM have demonstrated ultra-high extremely possibly improving sensitivity over Si InGaAs/InP...
Digital alloy and random Al <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">0.85</sub> Ga xmlns:xlink="http://www.w3.org/1999/xlink">0.15</sub> As xmlns:xlink="http://www.w3.org/1999/xlink">0.56</sub> Sb xmlns:xlink="http://www.w3.org/1999/xlink">0.44</sub> avalanche photodiodes (APDs) exhibit low excess noise, comparable to Si APDs. Consequently, this material is a promising multiplication layer candidate for separate absorption, charge,...
Germanium-on-Silicon (Ge-on-Si) avalanche photodiodes (APDs) are of considerable interest as low intensity light detectors for emerging applications. The Ge absorption layer detects at wavelengths up to ≈ 1600 nm with the Si acting an medium, providing high gain excess noise. Such APDs typically used in waveguide configurations growing a sufficiently thick absorbing is challenging. Here, we report on new vertically illuminated pseudo-planar Ge-on-Si APD design utilizing 2 µm absorber and 1.4...
The temperature dependence of the ionization coefficients AlAsSb has been determined from 210 K to 335 by measuring avalanche multiplication in a series three <i>p<sup>+</sup>-i-n<sup>+</sup></i> and two <i>n<sup>+</sup>-i-p<sup>+</sup></i> diodes. Both electron hole reduce at approximately same rate as increases but much less so than InAlAs or InP. This results significantly smaller breakdown voltage variation with 13 mV/K 1.55 μm thick structure...
Al0.85Ga0.15As0.56Sb0.44 has recently attracted significant research interest as a material for 1550 nm low-noise short-wave infrared (SWIR) avalanche photodiodes (APDs) due to the very wide ratio between its electron and hole ionization coefficients. This work reports new experimental excess noise data thick PIN NIP structures, measuring low at significantly higher multiplication values than previously reported (F = 2.2 M 38). These results disagree with classical McIntyre theory, which...
A hybrid quantum well/quantum dot active region is used to obtain simultaneous three-state lasing at room temperature, via ground state and first excited transitions of the dots lowest energy transition a single well. The device exhibits threshold current density 1125 A/cm2 for achieving over ∼160 nm.
AlxGa1-xAsySb1-y grown lattice-matched to InP has attracted significant research interest as a material for low noise, high sensitivity avalanche photodiodes (APDs) due its very dissimilar electron and hole ionization coefficients, especially at electric fields. All work reported date been on Al concentrations of x = 0.85 or higher. This demonstrates that much lower excess noise (F 2.4) multiplication 90 can be obtained in thick Al0.75Ga0.25As0.56Sb0.44 substrates. is the lowest any III-V...
For short-wavelength infrared (SWIR) avalanche photodiodes, a separate absorption, charge, and multiplication design is widely used. AlInAsSb on an InP substrate potential layer with lattice match to absorber candidates across the SWIR. Our new measurements demonstrate that promising multiplier candidate relatively low dark current density of 10−4 A/cm2 at gain 30; high gain, measured up 245 in this study; large differentiation electron hole ionization leading excess noise, be 2.5 30. These...
The avalanche multiplication and noise characteristics of Al0.55Ga0.45As0.56Sb0.44p–i–n n–i–p structures grown lattice matched on InP have been investigated. From measurements undertaken using 530 nm illumination several devices, the electron (α) hole (β) impact ionization coefficients determined. While α only shows a relatively small increase compared to higher Al composition alloys AlxGa1−xAsSb, β is found significantly. Although β/α ratio increased ∼0.125–0.2, than ∼0.003–0.02 seen in...
The increasing concentration of greenhouse gases, notably CH4 and CO2, has fueled global temperature increases, intensifying concerns regarding the prevailing climate crisis. Effectively monitoring these gases demands a detector spanning extended short-wavelength infrared (~2.4 {\mu}m) range, covering wavelengths (1.65 CO2 (2.05 {\mu}m). state-of-the-art HgCdTe avalanche photodetectors (APDs) offer exceptional performance metrics, including high gain (M) low excess noise (F). However, their...
The rising concentration of greenhouse gases, especially methane and carbon dioxide, is driving global temperature increases exacerbating the climate crisis. Monitoring these gases requires detectors that operate in extended short-wavelength infrared range (~2.4 µm), covering (1.65 µm) dioxide (2.05 wavelengths. Here, we present a high-performance linear mode avalanche photodetector (APD) with an InGaAs/GaAsSb type-II superlattice absorber AlGaAsSb multiplier, matched to InP substrates. This...
The presence of large bismuth (Bi) atoms has been shown to increase the spin-orbit splitting energy in bulk GaAsBi, reducing hole ionization coefficient (β) and thereby excess noise seen avalanche photodiodes. In this study, we show that even very thin layers GaAsBi introduced as quantum wells (QWs) a GaAs matrix exhibit significant reduction β while leaving electron coefficient, α, largely unchanged. optical multiplication properties series GaAsBi/GaAs multiple well (MQW) p-i-n structures...
The application of an electric field to a semiconductor can alter its absorption properties. This electroabsorption effect have significant impact on the quantum efficiency detector structures. photocurrents in bulk InGaAs and GaAsSb p-i-n photodiodes with intrinsic absorber layer thicknesses ranging from 1 4.8 μm been investigated. By using phase-sensitive photocurrent measurements as function wavelength, coefficients low cm−1 were extracted for fields up 200 kV/cm. Our findings show that...
The performance of the photodetector is often primary limiting factor affecting a free space communication or LiDAR system's sensitivity. Avalanche photodiodes (APDs) can be used to improve signal noise ratio (SNR) compared conventional <i>p-i-n</i> photodiodes. Our study focuses on demonstrating an APD operating in eye-safe short-wave infrared (SWIR) spectrum (>1400 nm) with high multiplication (<i>M</i>>1200) and low excess (<i>F</i><7 at <i>M</i>=200) room temperature. This...
Results from the development of substrate illuminated planar Ge on Si Single Photon Avalanche Diodes (SPAD) imaging arrays will be presented operating at short wave infrared wavelengths. Simulations have been used to optimize designs aiming reduce dark count rates and increase number absorbed photons for Pelter cooler operation whilst also minimizing cross talk. To date highest performance SPADs has demonstrated 125 K with 38% single photon detection efficiencies a noise equivalent power...
Detection in the short-wave infrared (SWIR) offers advantages like reduced solar noise and improved atmospheric transmission. Avalanche photodiodes (APDs) are ideal for low-light detection due to internal gain. While silicon (Si) APDs have low noise, they can't effectively detect SWIR light. Germanium (Ge) is good but suffers from high noise. Ge-on-Si structure benefits operation efficient multiplication. This study showcases room temperature of a linear-mode pseudo-planar APD with...
Single photon avalanche diodes (SPADs) are a key underpinning technology to many existing and emerging applications, including LIDAR for 3D imaging as well quantum imaging, encryption information applications. There is growing demand low-cost systems autonomous vehicles, particularly in the short-wave infrared (SWIR) spectral range, which enables long-range measurements whilst complying with eye-safety regulations offers enhanced transmission through atmospheric obscurants like smoke haze...