scholarly journals Simulation Study of Silicon-Based Single-Photon Avalanche Diodes with Double Buried Layers and Deep Trench Electrodes

Crystals ◽  
2021 ◽  
Vol 11 (10) ◽  
pp. 1176
Author(s):  
Yanyan Du ◽  
Bo Li ◽  
Xu Wang
Keyword(s):  
Electric Field ◽  
Near Infrared ◽  
Single Photon ◽  
Depletion Region ◽  
Simulation Software ◽  
Oxide Semiconductor ◽  
Infrared Band ◽  
Deep Trench ◽  
Buried Layers ◽  
Silicon Based

In this paper we present a study of a silicon-based Single-Photon Avalanche Diode (SPAD) in the near-infrared band with double buried layers and deep trench electrodes fabricated by the complimentary metal–oxide semiconductor (CMOS) technology. The deep trench electrodes aim to promote the movement of carriers in the device and reduce the transit time of the photo-generated carrier. The double buried layers are introduced to increase the electric field in the avalanche area and withstand a larger excess bias voltage as its larger depletion region. The semiconductor device simulation software TCAD is used to simulate the performance of this SPAD model, such as the I-V characteristic, the electric field and the Photon Detection Efficiency (PDE). Further optimization of the structure are studied with influence factors such as the doping concentration and depletion region thickness. Based on the results in this study, the designed a structure that can provide a high detecting efficiency in the near-infrared band.

scholarly journals A Near-Infrared Enhanced Silicon Single-Photon Avalanche Diode with a Spherically Uniform Electric Field Peak

2021 ◽  
pp. 1-1
Author(s):  
Edward Van Sieleghem ◽  
Andreas Suss ◽  
Pierre Boulenc ◽  
Jiwon Lee ◽  
Gauri Karve ◽  
...  
Keyword(s):  
Electric Field ◽  
Near Infrared ◽  
Single Photon ◽  
Uniform Electric Field ◽  
Avalanche Diode ◽  
Field Peak

Study on the Charge Collection Mechanism of Single Event Transient Effect for Nano N-Channel Metal Oxide Semiconductor Field Effect Transistor

2020 ◽  
Vol 15 (5) ◽  
pp. 637-644
Author(s):  
Minru Hao ◽  
Chenguang Liao ◽  
Qian Zhang ◽  
Yan Zhang ◽  
Min Shao ◽  
...  
Keyword(s):  
Electric Field ◽  
Integrated Circuit ◽  
Depletion Region ◽  
Transient Current ◽  
Oxide Semiconductor ◽  
Charge Collection ◽  
Gate Length ◽  
Single Event ◽  
Drain Bias ◽  
Peak Value

Based on the mechanism of charge collection, drift and diffusion, the influence of incident position, drain bias and incident particle LET (Linear Energy Transfer) value on the charge collection of NMOS devices is analyzed. It is found that the strongest electric field in drain depletion region is at 70 nm, and the maximum transient current is 3.43 mA. Drain bias affects the electric field in drain region. The higher drain bias is, the greater the electric field is, and the transient current is the larger of the peak value is, and the change of drain bias does not affect the diffusion current part; the larger the LET is, the larger the set current is, and the transient current peak value and collection charge increase linearly with the increase of LET. In addition, for a single transistor, the influence of the reduction of gate length on the bipolar amplification is analyzed, which is discovered that the reduction of gate length results in the aggravation of the single event effect. Therefore, the simulation results provide valuable reference for research on irradiation reliability and application of strained integrated circuit of Si Nano-scale NMOSFET.

scholarly journals Silicon Photomultipliers: Technology Optimizations for Ultraviolet, Visible and Near-Infrared Range

Instruments ◽  
2019 ◽  
Vol 3 (1) ◽  
pp. 15 ◽  
Author(s):  
Fabio Acerbi ◽  
Giovanni Paternoster ◽  
Massimo Capasso ◽  
Marco Marcante ◽  
Alberto Mazzi ◽  
...  
Keyword(s):  
Near Infrared ◽  
Detection Efficiency ◽  
Single Photon ◽  
High Energy ◽  
Infrared Light ◽  
Infrared Range ◽  
Silicon Photomultipliers ◽  
Deep Trench ◽  
Near Ultraviolet ◽  
Physics Experiments

Silicon photomultipliers (SiPMs) are single-photon sensitive solid-state detectors that are becoming popular for several applications, thanks to massive performance improvements over the last years. Starting as a replacement for the photomultiplier tube (PMT), they are now used in medical applications, big high-energy physics experiments, nuclear physics experiments, spectroscopy, biology and light detection and ranging (LIDAR) applications. Due to different requirements in terms of detection efficiency, noise, etc., several optimizations have been introduced by the manufacturers; for example, spectral sensitivity has been optimized for visible light, near ultraviolet, vacuum ultraviolet, and near infrared light. Each one of them require specific processes and structural optimization. We present in this paper recent improvements in SiPM performance, owing to a higher cell fill-factor, lower noise, improved silicon materials, and deep trench isolation. We describe issues related to the characterization of analog SiPM, particularly due to the different sources of correlated noise, which have to be distinguished from each other and from the primary pulses. We also describe particular analyses and optimizations conducted for specific applications like the readout of liquid noble gas scintillators, requiring these detectors to operate at cryogenic temperatures.

TEM study of Cosi2 formation via annealing of Co-Ti bilayers on Si

1995 ◽  
Vol 53 ◽  
pp. 464-465
Author(s):  
N. David Theodore ◽  
Andre Vantomme ◽  
Peter Crazier
Keyword(s):  
Thermal Instability ◽  
Lattice Mismatch ◽  
Field Effect Transistors ◽  
Contact Layer ◽  
Interface Roughness ◽  
Oxide Semiconductor ◽  
Surface Layers ◽  
Silicide Layer ◽  
Small Lattice ◽  
Buried Layers

Contact is typically made to source/drain regions of metal-oxide-semiconductor field-effect transistors (MOSFETs) by use of TiSi2 or CoSi2 layers followed by AI(Cu) metal lines. A silicide layer is used to reduce contact resistance. TiSi2 or CoSi2 are chosen for the contact layer because these silicides have low resistivities (~12-15 μΩ-cm for TiSi2 in the C54 phase, and ~10-15 μΩ-cm for CoSi2). CoSi2 has other desirable properties, such as being thermally stable up to >1000°C for surface layers and >1100°C for buried layers, and having a small lattice mismatch with silicon, -1.2% at room temperature. During CoSi2 growth, Co is the diffusing species. Electrode shorts and voids which can arise if Si is the diffusing species are therefore avoided. However, problems can arise due to silicide-Si interface roughness (leading to nonuniformity in film resistance) and thermal instability of the resistance upon further high temperature annealing. These problems can be avoided if the CoSi2 can be grown epitaxially on silicon.

Mathematical model to predict the characteristics of polarization in dielectric materials: The concept of piezoelectrcity and electrostriction

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Mathematical Model ◽  
Electric Field ◽  
Lead Zirconate Titanate ◽  
Dielectric Material ◽  
Strain Curve ◽  
Dielectric Materials ◽  
Lead Zirconate ◽  
Simulation Software ◽  
Constitutive Law ◽  
Basic Material

Model was developed for the prediction of polarization characteristics in a dielectric material exhibiting piezoelectricity and electrostriction based on mathematical equations and MATLAB computer simulation software. The model was developed based on equations of polarization and piezoelectric constitutive law and the functional coefficient of Lead Zirconate Titanate (PZT) crystal material used was 2.3×10-6 m (thickness), the model further allows the input of basic material and calculation of parameters of applied voltage levels, applied stress, pressure, dielectric material properties and so on, to generate the polarization curve, strain curve and the expected deformation change in the material length charts. The mathematical model revealed that an application of 5 volts across the terminals of a 2.3×10-6 m thick dielectric material (PZT) predicted a 1.95×10-9 m change in length of the material, which indicates piezoelectric properties. Both polarization and electric field curve as well as strain and voltage curve were also generated and the result revealed a linear proportionality of the compared parameters, indicating a resultant increase in the electric field yields higher polarization of the dielectric materials atmosphere.

High-performance near-infrared photodetectors based on C3N quantum dots integrated with single-crystal graphene

2021 ◽  
Author(s):  
Yun Zhao ◽  
Xiaoqiang Feng ◽  
Menghan Zhao ◽  
Xiaohu Zheng ◽  
Zhiduo Liu ◽  
...  
Keyword(s):  
Quantum Dots ◽  
Electric Field ◽  
Single Crystal ◽  
High Performance ◽  
Near Infrared ◽  
Fast Response ◽  
Local Electric Field ◽  
Infrared Photodetectors ◽  
Photocurrent Response

Employing C3N QD-integrated single-crystal graphene, photodetectors exhibited a distinct photocurrent response at 1550 nm. The photocurrent map revealed that the fast response derive from C3N QDs that enhanced the local electric field near graphene.

scholarly journals The slope of cerebral oxyhemoglobin oscillation is associated with vascular reserve capacity in large artery steno-occlusion

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Tae Jung Kim ◽  
Jae-Myoung Kim ◽  
Soo-Hyun Park ◽  
Jong-Kwan Choi ◽  
Hyeon-Min Bae ◽  
...  
Keyword(s):  
Cerebral Artery ◽  
Near Infrared ◽  
Single Photon ◽  
Photon Emission ◽  
Emission Computed Tomography ◽  
Large Artery ◽  
Anterior Circulation ◽  
Functional Near Infrared Spectroscopy ◽  
Vascular Reserve ◽  
Photon Emission Computed Tomography

AbstractInadequate cerebral perfusion is a risk factor for cerebral ischemia in patients with large artery steno-occlusion. We investigated whether prefrontal oxyhemoglobin oscillation (ΔHbO2, 0.6–2 Hz) was associated with decreased vascular reserve in patients with steno-occlusion in the large anterior circulation arteries. Thirty-six patients with steno-occlusion in the anterior circulation arteries (anterior cerebral artery, middle cerebral artery, and internal carotid artery) were included and compared to thirty-six control subjects. Patients were categorized into two groups (deteriorated vascular reserve vs. preserved vascular reserve) based on the results of Diamox single- photon emission computed tomography imaging. HbO2 data were collected using functional near-infrared spectroscopy. The slope of ΔHbO2 and the ipsilateral/contralateral slope ratio of ΔHbO2 were analyzed. Among the included patients (n = 36), 25 (69.4%) had deteriorated vascular reserve. Patients with deteriorated vascular reserve had a significantly higher average slope of ΔHbO2 on the ipsilateral side (5.01 ± 2.14) and a higher ipsilateral/contralateral ratio (1.44 ± 0.62) compared to those with preserved vascular reserve (3.17 ± 1.36, P = 0.014; 0.93 ± 0.33, P = 0.016, respectively) or the controls (3.82 ± 1.69, P = 0.019; 0.94 ± 0.29, P = 0.001). The ipsilateral/contralateral ΔHbO2 ratio could be used as a surrogate for vascular reserve in patients with severe steno-occlusion in the anterior circulation arteries.

scholarly journals The Equivalent Thermal Conductivity of the Micro/Nano Scaled Periodic Cubic Frame Silver and Its Thermal Radiation Mechanism Analysis

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4158
Author(s):  
Haiyan Yu ◽  
Haochun Zhang ◽  
Heming Wang ◽  
Dong Zhang
Keyword(s):  
Thermal Conductivity ◽  
Thermal Radiation ◽  
Cell Size ◽  
Near Infrared ◽  
High Porosity ◽  
Mechanism Analysis ◽  
Infrared Band ◽  
Spectral Radiation ◽  
Radiation Mechanism ◽  
Equivalent Thermal Conductivity

Currently, there are few studies on the influence of microscale thermal radiation on the equivalent thermal conductivity of microscale porous metal. Therefore, this paper calculated the equivalent thermal conductivity of high-porosity periodic cubic silver frame structures with cell size from 100 nm to 100 µm by using the microscale radiation method. Then, the media radiation characteristics, absorptivity, reflectivity and transmissivity were discussed to explain the phenomenon of the radiative thermal conductivity changes. Furthermore, combined with spectral radiation properties at the different cross-sections and wavelength, the radiative transmission mechanism inside high-porosity periodic cubic frame silver structures was obtained. The results showed that the smaller the cell size, the greater radiative contribution in total equivalent thermal conductivity. Periodic cubic silver frames fluctuate more in the visible band and have better thermal radiation modulation properties in the near infrared band, which is formed by the Surface Plasmon Polariton and Magnetic Polaritons resonance jointly. This work provides design guidance for the application of this kind of periodic microporous metal in the field of thermal utilization and management.

scholarly journals Low-Light Photodetectors for Fluorescence Microscopy

2021 ◽  
Vol 11 (6) ◽  
pp. 2773
Author(s):  
Hiroaki Yokota ◽  
Atsuhito Fukasawa ◽  
Minako Hirano ◽  
Toru Ide
Keyword(s):  
Fluorescence Microscopy ◽  
Fluorescence Imaging ◽  
Single Molecule ◽  
Science Studies ◽  
Single Photon ◽  
Laser Scanning Microscopy ◽  
Oxide Semiconductor ◽  
Wide Field ◽  
Single Molecule Fluorescence ◽  
Low Light

Over the years, fluorescence microscopy has evolved and has become a necessary element of life science studies. Microscopy has elucidated biological processes in live cells and organisms, and also enabled tracking of biomolecules in real time. Development of highly sensitive photodetectors and light sources, in addition to the evolution of various illumination methods and fluorophores, has helped microscopy acquire single-molecule fluorescence sensitivity, enabling single-molecule fluorescence imaging and detection. Low-light photodetectors used in microscopy are classified into two categories: point photodetectors and wide-field photodetectors. Although point photodetectors, notably photomultiplier tubes (PMTs), have been commonly used in laser scanning microscopy (LSM) with a confocal illumination setup, wide-field photodetectors, such as electron-multiplying charge-coupled devices (EMCCDs) and scientific complementary metal-oxide-semiconductor (sCMOS) cameras have been used in fluorescence imaging. This review focuses on the former low-light point photodetectors and presents their fluorescence microscopy applications and recent progress. These photodetectors include conventional PMTs, single photon avalanche diodes (SPADs), hybrid photodetectors (HPDs), in addition to newly emerging photodetectors, such as silicon photomultipliers (SiPMs) (also known as multi-pixel photon counters (MPPCs)) and superconducting nanowire single photon detectors (SSPDs). In particular, this review shows distinctive features of HPD and application of HPD to wide-field single-molecule fluorescence detection.

Sign in / Sign up

Export Citation Format

Share Document