Double-layer Silicon Research Articles

CMOS-Compatible Wafer-Level Double-layer Silicon Nanograss through Reactive Ion Etching for Applications in Optics

CMOS-Compatible Wafer-Level Double-layer Silicon Nanograss through Reactive Ion Etching for Applications in Optics

Mid-infrared bimodal wide metamaterial absorber based on double-layer silicon nitride structure

Infrared band occupies a very important position in the electromagnetic wave band. Traditional infrared devices use the inherent properties of natural materials to achieve the regulation of electromagnetic waves, but the limited ability of such devices to regulate electromagnetic waves can't well meet our needs. In this paper, we reported a metamaterial absorber of Cr-Si3N4-Cr-Si3N4-Ti based on double-layer metal-insulator-metal (MIM). It is investigated with the optimal structural parameters of 490 nm, 330 nm, 30 nm, 720 nm, 120 nm, in descending order, at which the absorptive properties are studied. When the light wave is incident vertically, it can be obtained from the experimental simulation that this absorber has polarisation insensitivity. Because of the coupling effect of the surface plasmon resonance and the high-loss material, the bandwidth of absorption greater than 90% can reach 9190 nm, and the average absorption in the target long-wave infrared band (9.506∼18.145 μm) is 94.8%. By selecting different geometrical parameters of the structure, the absorption spectrum can be adjusted independently. In addition, the absorber has good incident angle insensitivity in TE and TM modes. Also, the absorber we proposed has a plain structure, is convenient for manufacturing, the material is easier to obtain, which ensures a good absorption bandwidth and average absorptivity, and the study of this metamaterial absorber has important applications in solar cells, satellite radiothermographs, photodetectors, and spectral imaging.

Vertical Grating Coupler Based on Double-Layer Silicon Nitride Antireflection

Vertical Grating Coupler Based on Double-Layer Silicon Nitride Antireflection

Quasi-bound states in continuum in double-layer silicon gratings

Bound states in the continuum (BICs) are theoretically known to possess infinite lifetimes and Q factor. However, due to the difficulties in achieving it in reality, symmetry breaking is often introduced in the structure to transform symmetrically protected BICs into quasi-BICs (q-BICs) with extremely high Q factor. Therefore, q-BICs can be utilized to enhance the Q factor of optical sensors. In this paper, we propose the design of a double-layer composite one-dimensional grating with a high Q factor. The structure consists of a double-layers silicon (Si) grating on a silicon dioxide (SiO2) substrate. By introducing a displacement in the upper-layer grating to break the symmetry, q-BICs are induced. The induced q-BICs achieve a Q factor of 2248 for transverse magnetic (TM) wave, enabling enhanced optical sensing capabilities. The proposed q-BICs sensor, exhibiting anisotropy for both TM and transverse electric wave (TE), holds great potential for narrowband polarizers and sensing applications.

Study on PID performance degradation based on passivation materials such as alumina/silicon nitride SiN crystalline silicon solar cells

Solar energy is a pure and reproducible energy. China has paid more and more consideration to the investigation and employment of solar energy. The investigation focuses on the phenomenon of PID capability degradation of inactivation mediums for instance alumina/silicon nitride in transparent silicon high-efficiency solar cells. Through the laboratorial investigation on the effect of individual in-activation membrane processes on the PID damping behavior, it is found that the deposition approach of silicon oxide and silicon nitride inactivation membranes on the surface of transparent silicon cells directly affects the PID damping. Excellent anti-PID capability; single-layer silicon oxide membrane with the same thickness has better anti-PID capability than silicon nitride membrane. Double-layer silicon oxide/silicon nitride superimposed membrane with the enhancement of refractive index, the anti-PID damping capability gradually enhancements, and better anti-PID capability than monolayer silicon nitride. Investigation on the PID capability damping of inactivation mediums is of great significance to further the capability of solar cells and help to further the effective employment of solar energy.

Beam test studies with silicon sensor module prototypes for the CMS Phase-2 Outer Tracker

The Large Hadron Collider (LHC) at CERN will be upgraded to the High-Luminosity LHC (HL-LHC) by 2029. In order to fully exploit the physics potential of the high luminosity era the experiments must undergo major upgrades. In the context of the upgrade of the Compact Muon Solenoid (CMS) experiment the silicon tracker will be fully replaced. The outer part of the new tracker (Outer Tracker) will be equipped with about 13,000 double-layer silicon sensor modules with two different flavors: PS modules consisting of a macro-pixel and a strip sensor and 2S modules using two strip sensors. These modules can discriminate between trajectories of charged particles with low and high transverse momentum. The different curvature of the trajectories in the CMS magnetic field leads to different hit signatures in the two sensor layers. By reading out both sensors, matching hits in the seed and correlation layer “stubs” are identified. This stub information is generated at the LHC bunch crossing frequency of 40 MHz and serves as input for the first stage of the CMS trigger. In order to quantify the hit and stub detection efficiency, beam tests have been performed. This article comprises selected studies from measurements gathered during two beam tests at the DESY test beam facility with 2S prototype modules assembled in 2021, featuring the Low Power Gigabit Transceiver (lpGBT). In order to compare the module performance at the beginning and end of the CMS runtime, a module with irradiated components has been built and intensively tested.

Design and Optimization of an S-Band MEMS Bandpass Filter Based on Aggressive Space Mapping.

Aggressive space mapping (ASM) is a common filter simulation and debugging method. It plays an important role in the field of microwave device design. This paper introduces ASM and presents the design and fabrication of a compact fifth-order microstrip interdigital filter with a center frequency of 2.5 GHz and a relative bandwidth of 10% using ASM. The filter used a double-layer silicon substrate structure and stepped impedance resonators (SIRs) and was optimized by ASM. After five iterations, the filter achieved the design specification, which greatly improves the efficiency of the filter design compared with the traditional method. It was fabricated on high-resistance silicon wafers by micro-electro-mechanical systems (MEMSs) technology, and the final size of the chip is 9.5 mm × 7.6 mm × 0.8 mm. The measurement results show that the characteristics of the filter are similar to the simulation results, which also shows the efficiency and precision of the ASM algorithm.

The edge-coupler of fiber-to-chip with ultra-low coupling loss based on double-layer silicon waveguides

The edge-coupler of fiber-to-chip with ultra-low coupling loss is demonstrated on SOI platform. The edge-coupler is consisted of the cantilevered SiO2 waveguide, the amorphous silicon (α-Si) nano taper and the crystal silicon (c-Si) nano tapers. The thin α-Si layer is deposited on the c-Si layer to improve the pattern matching with fiber. The optical input signal from the optical fiber is launched into the suspended SiO2 waveguide, then coupled into the α-Si nano taper at the center of the SiO2 waveguide, and finally coupled into the c-Si nano taper. We characterized the cantilevered edge-coupler using cleaved single-mode optical fiber with a mode field diameter of 10.5 μm. The measured coupling loss is as low as -1.7 dB per facet for TE mode without index matching liquid at 1550 nm. The 1 dB bandwidth is more than 100 nm with 1 dB alignment tolerances of ±2.0 μm in both horizontal and vertical directions. Besides, potential hybrid optical integration could also be allowed with this results in the future.

A new core-shell magnetic mesoporous surface molecularly imprinted composite and its application as an MSPE sorbent for determination of phthalate esters.

In this study, a new core–shell magnetic mesoporous surface molecularly imprinted polymer (Fe3O4@SiO2@mSiO2-MIPs) which has specific adsorption and rapid adsorption rate for phthalate esters (PAEs) was prepared by a convenient method. Based on this composite as a magnetic solid phase extraction (MSPE) material, a rapid, efficient and sensitive matrix dispersion magnetic solid-phase extraction gas chromatography-mass spectrometry method (DMSPE-GC/MS) was developed for the determination of PAEs in multiple liquid samples. It is the first time that Fe3O4@SiO2@mSiO2-MIPs have been prepared by bonding amino groups on the surface of a double layer silicon substrate with diisononyl phthalate (DINP) as virtual template and 3-(2-aminoethyl)-aminopropyl trimethoxymethylsilane (TSD) as functional monomer. FT-IR, TEM, EDS, SEM, XRD, BET and VSM were used to characterize the composite. The adsorption isotherm and kinetics of Fe3O4@SiO2@mSiO2-MIPs showed that it possessed fast adsorption rates (approximately 5 min to reach equilibrium), high adsorption capacities (523.9 mg g−1) and good recognition of PAEs. The real samples were preconcentrated by Fe3O4@SiO2@mSiO2-MIPs, under the optimum DMSPE-GC/MS conditions. Validation experiments showed that the method presented good linearity (R2 > 0.9971), satisfactory precision (RSD < 5.7%) and high recovery (92.1–105.8%), and the limits of detection ranged from 1.17 ng L−1 to 3.03 ng L−1. The results indicated that the novel method had good sensitivity, high efficiency and wide sample application and was suitable for the determination of PAEs in liquid drink samples such as water, alcohol, beverages and so on.

The Edge-Coupler of Fiber-to-Chip with Ultra-Low Coupling Loss Based on Double-Layer Silicon Waveguides

The Edge-Coupler of Fiber-to-Chip with Ultra-Low Coupling Loss Based on Double-Layer Silicon Waveguides

Silicon nitride assisted 1×64 optical phased array based on a SOI platform

We demonstrate a 1×64 optical phased array (OPA) based on a silicon on insulator (SOI) platform with integrated silicon nitride. The input port of the OPA is fabricated using a silicon nitride waveguide due to its advantage of allowing more optical power. The phase shifter is a silicon waveguide with heater because of the higher thermo-optic coefficient of silicon. And a double layer silicon nitride assisted grating is used in the emitter to reduce the emission strength and then increase the length of emitter to reduce the spot size. The length of the grating emitter is 1.5 mm and the measured field of view of this optical phased array is 35.5°×22.7° with spot size of 0.69°×0.075°.

Effect of the presence of trap states in oxides in modeling gate leakage current in advanced MOSFET with multi-oxide stack

Abstract A model of trap assisted tunneling due to the presence of trap states distributed over the oxide and at the interface has been introduced to develop a complete analytical model for gate tunneling current in advanced nano-scale MOSFET in addition to the ideal direct tunneling current with double layer silicon oxide-Hafnium Oxide stack used as gate dielectric. Trapping-detrapping of charge carriers is mostly subjected to multiphonon transitions and thus is dependent on temperature, gate bias and the distribution of trap states across oxide. Relative contribution of the direct tunneling and trap-assisted tunneling has been estimated even in the Fowler-Nordheim regime. The assumption of simplified parabolic energy band dispersion with proper boundary conditions in Wentzel-Kramers-Brillouin (WKB) effective mass approximation is employed to determine the probability density of electrons at different materials throughout the MOS structure. It is then modulated by the tunneling probability to estimate the total amount of tunneling current as a function of effective oxide thickness and gate-biasing.

The design and performance of the nano-carbon based double layers flexible coating for tunable and high-efficiency microwave absorption

Nanocarbon-based materials are outstanding microwave absorbers with good dielectric properties. In this study, double-layer silicone resin flexible absorbing coatings, composed of carbon-coated nickel nanoparticles (Ni@C) and carbon nanotubes (CNTs), with low loading and a total thickness of 2 mm, were prepared. The reflection loss (RL) of the double-layer absorbing coatings has measured for frequencies between 2 and 18 GHz using the Arch reflecting testing method. The effects of the thickness and electromagnetic parameters of each layer and of the layer sequence on the absorbing properties were investigated. It is found that the measured bandwidth (RL ≤ − 10 dB) of the optimum double-layer structure in our experiment range achieves 3.70 GHz. The results indicated that the double coating structure composed of different materials has greater synergistic absorption effect on impedance matching than that of same materials with different loading. The maximum RL of S1 (5 wt% CNTs)/S3 (60 wt% Ni@C) double-layer absorbing coating composed of different materials (S1 and S3) was larger than the one achieved using either S1 or S3 alone with the same thickness. This was because double-layer coating provided a suitable matching layer and improve the interfacial impedance. It was also shown that absorbing peak value and frequency position can be adjusted by double-layer coating structure.

Transferable micromachined piezoresistive force sensor with integrated double-meander-spring system

Abstract. A developed transferable micro force sensor was evaluated by comparing its response with an industrially manufactured device. In order to pre-identify sensor properties, three-dimensional (3-D) sensor models were simulated with a vertically applied force up to 1000 µN. Then, controllable batch fabrication was performed by alternately utilizing inductively coupled plasma (ICP) reactive ion etching (RIE) and photolithography. The assessments of sensor performance were based on sensor linearity, stiffness and sensitivity. Analysis of the device properties revealed that combination of a modest stiffness value (i.e., (8.19 ± 0.07) N m−1) and high sensitivity (i.e., (15.34 ± 0.14) V N−1) at different probing position can be realized using a meander-spring configuration. Furthermore, lower noise voltage is obtained using a double-layer silicon on insulator (DL-SOI) as basic material to ensure high reliability and an excellent performance of the sensor.

Test beam results of the first CMS double-sided strip module prototypes using the CBC2 read-out chip

The CMS Binary Chip (CBC) is a prototype version of the front-end read-out ASIC to be used in the silicon strip modules of the CMS outer tracking detector during the high luminosity phase of the LHC. The CBC is produced in 130nm CMOS technology and bump-bonded to the hybrid of a double layer silicon strip module, the so-called 2S-pT module. It has 254 input channels and is designed to provide on-board trigger information to the first level trigger system of CMS, with the capability of cluster-width discrimination and high-pT track identification. In November 2013 the first 2S-pT module prototypes equipped with the CBC chips were put to test at the DESY-II test beam facility. Data were collected exploiting a beam of positrons with an energy ranging from 2 to 4GeV. In this paper the test setup and the results are presented.

Transfer Printed Nanomembranes for Heterogeneously Integrated Membrane Photonics

Heterogeneous crystalline semiconductor nanomembrane (NM) integration is investigated for single-layer and double-layer Silicon (Si) NM photonics, III-V/Si NM lasers, and graphene/Si NM total absorption devices. Both homogeneous and heterogeneous integration are realized by the versatile transfer printing technique. The performance of these integrated membrane devices shows, not only intact optical and electrical characteristics as their bulk counterparts, but also the unique light and matter interactions, such as Fano resonance, slow light, and critical coupling in photonic crystal cavities. Such a heterogeneous integration approach offers tremendous practical application potentials on unconventional, Si CMOS compatible, and high performance optoelectronic systems.

Double layer adhesive silicone dressing as a potential dermal drug delivery film in scar treatment

The present studies focused on the evaluation of design of an adhesive silicone film intended for scar treatment. Developed silicone double layer film was examined in terms of its future relevance to therapy and applicability on the human skin considering properties which included in vitro permeability of water vapor and oxygen. In order to adapt the patches for medical use in the future there were tested such properties as in vitro adhesion and occlusion related to in vivo hydration. From the silicone rubbers double layer silicone film was prepared: a non-adhesive elastomer as a drug carrier (the matrix for active substances – enoxaparin sodium – low molecular weight heparin) and an adhesive elastomer, applied on the surface of the matrix. The novel adhesive silicone film was found to possess optimal properties in comparison to commercially available silicone dressing: adhesion in vivo, adhesion in vitro – 11.79N, occlusion F=85% and water vapor permeability in vitro – WVP=105g/m2/24h, hydration of stratum corneum in vivoH=61–89 (RSD=1.6–0.9%), oxygen permeation in vitro – 119–391cm3/m2/24 (RSD=0.17%). In vitro release studies indicated sufficient LMWH release rate from silicone matrix. Developed novel adhesive silicone films were considered an effective treatment of scars and keloids and a potential drug carrier able to improve the effectiveness of therapy.

MEMS patch antenna array with broadband and high-gain on double-layer silicon wafers

A MEMS patch antenna which can be integrated with RF module easily was designed to improve the bandwidth and gain of the traditional microstrip antenna. The equivalent dielectric constant of substrate of the microstrip antenna was optimized to greatly increase the bandwidth of the antenna by a high resistivity silicon being bonded to a low resistivity silicon to form a double-layer silicon substrate under the MEMS technology. Defected ground structure was also used on ground plane in order to restrain the harmonic radiation of antenna. Based on the above aspects, a 22 antenna array was designed with a center frequency of 10 GHz. The simulation results show that the antenna array has an impendence bandwidth of 15.9% and a gain of 10.9 dB, significantly better than traditional antennas and meets the anti-interference requirements of antennas in the fuze.

宽带高增益双层硅基MEMS微带天线阵列

宽带高增益双层硅基MEMS微带天线阵列

Double-Layer Crystalline Silicon on Insulator Material Platform for Integrated Photonic Applications

We report a high optical-quality double-layer silicon (Si) material platform with a thin interface oxide using a low-temperature wafer bonding technique. To assess the quality of the platform, resonators with different radii are fabricated, and their quality factors (Q) are measured. Q's of 25 k and 350 k are demonstrated in 2- $\mu{\rm m}$ - and 20- $\mu{\rm m}$ -radius microring resonators, respectively. The former is the most compact high-Q resonator demonstrated in any type of double-layer Si platform, and the latter is the highest Q demonstrated in a double-layer Si platform to date. This material platform enables a new set of integrated optical devices for a wide range of applications, including high-speed modulators, tunable filters, and low-power switches.