Optical Constants of Chemical Vapor Deposited Graphene for Photonic Applications

Graphene is a promising building block material for developing novel photonic and optoelectronic devices. Here, we report a comprehensive experimental study of chemical-vapor deposited (CVD) monolayer graphene’s optical properties on three different substrates for ultraviolet, visible, and near-infrared spectral ranges (from 240 to 1000 nm). Importantly, our ellipsometric measurements are free from the assumptions of additional nanometer-thick layers of water or other media. This issue is critical for practical applications since otherwise, these additional layers must be included in the design models of various graphene photonic, plasmonic, and optoelectronic devices. We observe a slight difference (not exceeding 5%) in the optical constants of graphene on different substrates. Further, the optical constants reported here are very close to those of graphite, which hints on their applicability to multilayer graphene structures. This work provides reliable data on monolayer graphene’s optical properties, which should be useful for modeling and designing photonic devices with graphene.

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A Molecular Chameleon: Reversible pH- and Cation-Induced Control of the Optical Properties of Phthalocyanine-Based Complexes in the Visible and Near-Infrared Spectral Ranges

Inorganic Chemistry ◽

10.1021/acs.inorgchem.5b02831 ◽

2016 ◽

Vol 55 (5) ◽

pp. 2450-2459 ◽

Cited By ~ 28

Author(s):

Evgeniya A. Safonova ◽

Alexander G. Martynov ◽

Sergey E. Nefedov ◽

Gayane A. Kirakosyan ◽

Yulia G. Gorbunova ◽

...

Keyword(s):

Optical Properties ◽

Near Infrared ◽

Infrared Spectral ◽

Spectral Ranges

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Size Effect on Optical Properties of Silicon Dioxide Hollow Particles

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.312.26 ◽

2020 ◽

Vol 312 ◽

pp. 26-31

Author(s):

Viktoriia Iurina ◽

Vitaly V. Neshchimenko ◽

Chun Dong Li

Keyword(s):

Optical Properties ◽

Silicon Dioxide ◽

Near Infrared ◽

Photoelectron Spectra ◽

Hollow Particles ◽

X Ray ◽

Near Ir ◽

Infrared Spectral ◽

Uv Visible ◽

Spectral Ranges

The optical properties of silicon dioxide hollow particles with different size were investigated in UV/visible/near-IR region, as well as X-ray photoelectron spectra were analyzed. Synthesis of SiO2 hollow particles was carried out using a template method. It was established that hollow particle reflectance lower than bulk microparticles. Absorptance in the red and near infrared spectral ranges increases with decreasing size of hollow particles, but in the UV-region conversely. This is due to different absorption centers.

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Ion Beam Induced Interfacial Reactions in Molybdenum Thin Films on Silicon

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100097466 ◽

1981 ◽

Vol 39 ◽

pp. 162-163

Author(s):

L. J. Chen ◽

L. S. Hung ◽

J. W. Mayer

Keyword(s):

Ion Beam ◽

Chemical Vapor ◽

Interfacial Reactions ◽

Practical Applications ◽

Microelectronic Devices ◽

Recent Emergence ◽

Chemical Vapor Deposited ◽

Atomic Mixing ◽

Silicon Interface ◽

Kinetics Of

When an energetic ion penetrates through an interface between a thin film (of species A) and a substrate (of species B), ion induced atomic mixing may result in an intermixed region (which contains A and B) near the interface. Most ion beam mixing experiments have been directed toward metal-silicon systems, silicide phases are generally obtained, and they are the same as those formed by thermal treatment.Recent emergence of silicide compound as contact material in silicon microelectronic devices is mainly due to the superiority of the silicide-silicon interface in terms of uniformity and thermal stability. It is of great interest to understand the kinetics of the interfacial reactions to provide insights into the nature of ion beam-solid interactions as well as to explore its practical applications in device technology.About 500 Å thick molybdenum was chemical vapor deposited in hydrogen ambient on (001) n-type silicon wafer with substrate temperature maintained at 650-700°C. Samples were supplied by D. M. Brown of General Electric Research & Development Laboratory, Schenectady, NY.

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The Effect of Nitrogen Incorporation on the Optical Properties of Si-Rich a-SiCx Films Deposited by VHF PECVD

Micromachines ◽

10.3390/mi12060637 ◽

2021 ◽

Vol 12 (6) ◽

pp. 637

Author(s):

Hongliang Li ◽

Zewen Lin ◽

Yanqing Guo ◽

Jie Song ◽

Rui Huang ◽

...

Keyword(s):

Optical Properties ◽

Near Infrared ◽

Chemical Vapor ◽

Wide Bandgap ◽

Nonradiative Recombination ◽

Very High Frequency ◽

N Content ◽

High Frequency Plasma ◽

Frequency Plasma ◽

N Incorporation

The influence of N incorporation on the optical properties of Si-rich a-SiCx films deposited by very high-frequency plasma-enhanced chemical vapor deposition (VHF PECVD) was investigated. The increase in N content in the films was found to cause a remarkable enhancement in photoluminescence (PL). Relative to the sample without N incorporation, the sample incorporated with 33% N showed a 22-fold improvement in PL. As the N content increased, the PL band gradually blueshifted from the near-infrared to the blue region, and the optical bandgap increased from 2.3 eV to 5.0 eV. The enhancement of PL was suggested mainly from the effective passivation of N to the nonradiative recombination centers in the samples. Given the strong PL and wide bandgap of the N incorporated samples, they were used to further design an anti-counterfeiting label.

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Metalorganic chemical vapor deposition of InN quantum dots and nanostructures

Light Science & Applications ◽

10.1038/s41377-021-00593-8 ◽

2021 ◽

Vol 10 (1) ◽

Author(s):

Caroline E. Reilly ◽

Stacia Keller ◽

Shuji Nakamura ◽

Steven P. DenBaars

Keyword(s):

Quantum Dots ◽

Chemical Vapor Deposition ◽

Vapor Deposition ◽

Metalorganic Chemical Vapor Deposition ◽

Near Infrared ◽

Optoelectronic Devices ◽

Chemical Vapor ◽

Electromagnetic Spectrum ◽

Material System ◽

Metalorganic Chemical

AbstractUsing one material system from the near infrared into the ultraviolet is an attractive goal, and may be achieved with (In,Al,Ga)N. This III-N material system, famous for enabling blue and white solid-state lighting, has been pushing towards longer wavelengths in more recent years. With a bandgap of about 0.7 eV, InN can emit light in the near infrared, potentially overlapping with the part of the electromagnetic spectrum currently dominated by III-As and III-P technology. As has been the case in these other III–V material systems, nanostructures such as quantum dots and quantum dashes provide additional benefits towards optoelectronic devices. In the case of InN, these nanostructures have been in the development stage for some time, with more recent developments allowing for InN quantum dots and dashes to be incorporated into larger device structures. This review will detail the current state of metalorganic chemical vapor deposition of InN nanostructures, focusing on how precursor choices, crystallographic orientation, and other growth parameters affect the deposition. The optical properties of InN nanostructures will also be assessed, with an eye towards the fabrication of optoelectronic devices such as light-emitting diodes, laser diodes, and photodetectors.

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Integrated Optical Phased Arrays for Beam Forming and Steering

Applied Sciences ◽

10.3390/app11094017 ◽

2021 ◽

Vol 11 (9) ◽

pp. 4017

Author(s):

Yongjun Guo ◽

Yuhao Guo ◽

Chunshu Li ◽

Hao Zhang ◽

Xiaoyan Zhou ◽

...

Keyword(s):

Near Infrared ◽

Phased Arrays ◽

Mechanical Stability ◽

Building Blocks ◽

High Yield ◽

Beam Forming ◽

Integrated Optical ◽

Optical Phased Arrays ◽

Infrared Spectral ◽

Spectral Ranges

Integrated optical phased arrays can be used for beam shaping and steering with a small footprint, lightweight, high mechanical stability, low price, and high-yield, benefiting from the mature CMOS-compatible fabrication. This paper reviews the development of integrated optical phased arrays in recent years. The principles, building blocks, and configurations of integrated optical phased arrays for beam forming and steering are presented. Various material platforms can be used to build integrated optical phased arrays, e.g., silicon photonics platforms, III/V platforms, and III–V/silicon hybrid platforms. Integrated optical phased arrays can be implemented in the visible, near-infrared, and mid-infrared spectral ranges. The main performance parameters, such as field of view, beamwidth, sidelobe suppression, modulation speed, power consumption, scalability, and so on, are discussed in detail. Some of the typical applications of integrated optical phased arrays, such as free-space communication, light detection and ranging, imaging, and biological sensing, are shown, with future perspectives provided at the end.

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Copper-graphene heterostructure for back-end-of-line compatible high-performance interconnects

npj 2D Materials and Applications ◽

10.1038/s41699-021-00216-1 ◽

2021 ◽

Vol 5 (1) ◽

Author(s):

Myungwoo Son ◽

Jaewon Jang ◽

Yongsu Lee ◽

Jungtae Nam ◽

Jun Yeon Hwang ◽

...

Keyword(s):

High Performance ◽

Direct Synthesis ◽

Chemical Vapor ◽

Multilayer Graphene ◽

Time To Failure ◽

Practical Applications ◽

Cu Interconnects ◽

Pressure Chemical ◽

Cu Interconnect ◽

Pure Cu

AbstractHere, we demonstrate the fabrication of a Cu-graphene heterostructure interconnect by the direct synthesis of graphene on a Cu interconnect with an enhanced performance. Multilayer graphene films were synthesized on Cu interconnect patterns using a liquid benzene or pyridine source at 400 °C by atmospheric pressure chemical vapor deposition (APCVD). The graphene-capped Cu interconnects showed lower resistivity, higher breakdown current density, and improved reliability compared with those of pure Cu interconnects. In addition, an increase in the carrier density of graphene by doping drastically enhanced the reliability of the graphene-capped interconnect with a mean time to failure of >106 s at 100 °C under a continuous DC stress of 3 MA cm−2. Furthermore, the graphene-capped Cu heterostructure exhibited enhanced electrical properties and reliability even if it was a damascene-patterned structure, which indicates compatibility with practical applications such as next-generation interconnect materials in CMOS back-end-of-line (BEOL).

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High performing flexible optoelectronic devices using thin films of topological insulator

Scientific Reports ◽

10.1038/s41598-020-80738-8 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Animesh Pandey ◽

Reena Yadav ◽

Mandeep Kaur ◽

Preetam Singh ◽

Anurag Gupta ◽

...

Keyword(s):

Thin Films ◽

Optical Properties ◽

Nonlinear Optical ◽

Near Infrared ◽

Optoelectronic Devices ◽

Nonlinear Optical Properties ◽

Metallic Surface ◽

Strong Light ◽

High Performing ◽

Decay Times

AbstractTopological insulators (TIs) possess exciting nonlinear optical properties due to presence of metallic surface states with the Dirac fermions and are predicted as a promising material for broadspectral phodotection ranging from UV (ultraviolet) to deep IR (infrared) or terahertz range. The recent experimental reports demonstrating nonlinear optical properties are mostly carried out on non-flexible substrates and there is a huge demand for the fabrication of high performing flexible optoelectronic devices using new exotic materials due to their potential applications in wearable devices, communications, sensors, imaging etc. Here first time we integrate the thin films of TIs (Bi2Te3) with the flexible PET (polyethylene terephthalate) substrate and report the strong light absorption properties in these devices. Owing to small band gap material, evolving bulk and gapless surface state conduction, we observe high responsivity and detectivity at NIR (near infrared) wavelengths (39 A/W, 6.1 × 108 Jones for 1064 nm and 58 A/W, 6.1 × 108 Jones for 1550 nm). TIs based flexible devices show that photocurrent is linearly dependent on the incident laser power and applied bias voltage. Devices also show very fast response and decay times. Thus we believe that the superior optoelectronic properties reported here pave the way for making TIs based flexible optoelectronic devices.

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