Barrier Performance of CVD Graphene Films Using a Facile P3HT Thin Film Optical Transmission Test

Journal of Nanomaterials ◽

10.1155/2018/9681432 ◽

2018 ◽

Vol 2018 ◽

pp. 1-11 ◽

Cited By ~ 1

Author(s):

Srinivasa Kartik Nemani ◽

Hossein Sojoudi

Keyword(s):

Thin Film ◽

Absorption Spectra ◽

Optical Transmission ◽

Screening Method ◽

Ambient Conditions ◽

Cvd Graphene ◽

Barrier Materials ◽

Graphene Films ◽

Barrier Performance ◽

Transmission Test

The barrier performance of CVD graphene films was determined using a poly(3-hexylthiophene) (P3HT) thin film optical transmission test. P3HT is a semiconducting polymer that photo-oxidatively degrades upon exposure to oxygen and light. The polymer is stable under ambient conditions and indoor lighting, enabling P3HT films to be deposited and encapsulated in air. P3HT’s stability under ambient conditions makes it desirable for an initial evaluation of barrier materials as a complimentary screening method in combination with conventional barrier tests. The P3HT test was used to demonstrate improved barrier performance for polymer substrates after addition of CVD graphene films. A layer-by-layer transfer method was utilized to enhance the barrier performance of monolayer graphene. Another set of absorption measurements were conducted to demonstrate the barrier performance of graphene and the degradation mechanism of graphene/P3HT over multiple wavelengths from 400 to 800 nm. The absorption spectra for graphene/polymer composite were simulated by solving Fresnel equations. The simulation results were found to be in good agreement with the measured absorption spectra. The P3HT degradation results qualitatively indicate the potential of graphene films as a possible candidate for medium performance barriers.

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Layer-by-Layer Assembled Transparent Conductive Graphene Films for Silicon Thin-Film Solar Cells

Japanese Journal of Applied Physics ◽

10.1143/jjap.51.11pf01 ◽

2012 ◽

Vol 51 ◽

pp. 11PF01 ◽

Cited By ~ 3

Author(s):

Ryousuke Ishikawa ◽

Masashi Bando ◽

Hidetoshi Wada ◽

Yasuyoshi Kurokawa ◽

Adarsh Sandhu ◽

...

Keyword(s):

Thin Film ◽

Solar Cells ◽

Thin Film Solar Cells ◽

Layer By Layer ◽

Silicon Thin Film ◽

Graphene Films

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Determination of Thermal Conductivity of Amorphous Silicon Thin Films via Non-Contacting Optical Probing

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.326-328.689 ◽

2006 ◽

Vol 326-328 ◽

pp. 689-692

Author(s):

Seung Jae Moon

Keyword(s):

Thin Film ◽

Thin Films ◽

Thermal Conductivity ◽

Amorphous Silicon ◽

Optical Transmission ◽

Film Deposition ◽

Transmission Measurement ◽

Conductive Heat ◽

Optical Transmission Measurement

The thermal conductivity of amorphous silicon (a-Si) thin films is determined by using the non-intrusive, in-situ optical transmission measurement. The thermal conductivity of a-Si is a key parameter in understanding the mechanism of the recrystallization of polysilicon (p-Si) during the laser annealing process to fabricate the thin film transistors with uniform characteristics which are used as switches in the active matrix liquid crystal displays. Since it is well known that the physical properties are dependent on the process parameters of the thin film deposition process, the thermal conductivity should be measured. The temperature dependence of the film complex refractive index is determined by spectroscopic ellipsometry. A nanosecond KrF excimer laser at the wavelength of 248 nm is used to raise the temperature of the thin films without melting of the thin film. In-situ transmission signal is obtained during the heating process. The acquired transmission signal is fitted with predictions obtained by coupling conductive heat transfer with multi-layer thin film optics in the optical transmission measurement.

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Structure analysis of CVD graphene films based on HRTEM contrast simulations

2011 11th IEEE International Conference on Nanotechnology ◽

10.1109/nano.2011.6144403 ◽

2011 ◽

Cited By ~ 4

Author(s):

Paul Plachinda ◽

Sergei Rouvimov ◽

Raj Solanki

Keyword(s):

Structure Analysis ◽

Cvd Graphene ◽

Graphene Films

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Laminated Graphene Films for Flexible Transparent Thin Film Encapsulation

ACS Applied Materials & Interfaces ◽

10.1021/acsami.6b01639 ◽

2016 ◽

Vol 8 (23) ◽

pp. 14725-14731 ◽

Cited By ~ 40

Author(s):

Hong-Kyu Seo ◽

Min-Ho Park ◽

Young-Hoon Kim ◽

Sung-Joo Kwon ◽

Su-Hun Jeong ◽

...

Keyword(s):

Thin Film ◽

Graphene Films ◽

Thin Film Encapsulation

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IMPROVING THE SHEET RESISTANCE OF CVD-GRAPHENE FILMS VIA DOPING

Anadolu Üniversitesi Bilim Ve Teknoloji Dergisi - B Teorik Bilimler ◽

10.20290/aubtdb.464140 ◽

2018 ◽

pp. 1-1 ◽

Cited By ~ 1

Author(s):

Gülsüm Ersü ◽

Fethullah Güneş ◽

Ahmet Aykaç ◽

Mustafa Can

Keyword(s):

Sheet Resistance ◽

Cvd Graphene ◽

Graphene Films

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Design and Analytical Evaluation of A High Resistance Sensitivity Bolometer Sensor Based on Plasmonic Metasurface Structure

10.21203/rs.3.rs-267998/v1 ◽

2021 ◽

Author(s):

Abbas Hamouleh-Alipour ◽

Ali Mir ◽

Ali Farmani

Keyword(s):

Thin Film ◽

Strong Coupling ◽

Absorption Spectra ◽

High Resistance ◽

Figure Of Merit ◽

Surface Mode ◽

Coupling Condition ◽

Resistance Change ◽

Strong Light ◽

Bolometric Effect

Abstract Bolometer sensors are prominent and excellent choice in technology because they do not need cooling. The trade-off between high sensitivity, fast response time, and strong light absorption is a key important challenge in bolometer sensors. Here, the bolometric effect for a high resistance sensitivity plasmonic sensing of total and profile infusion of radiation is studied for the proposed bolometer sensor based on plasmonic multilayer structure at 26° C. In the present study, by generating strong coupling condition between incident wave and surface plasmon polaritons (SPPs), a very narrow absorption spectra with high figure of merit (FoM) is achieved. The analytical model and numerical simulation are fulfilled based on the transfer matrix method (TMM) and 3-D finite-difference time-domain (FDTD), respectively. The narrow absorption spectra that generate by strong coupling with SPPs heats the silver thin film that leads to variation in temperature and supports TE surface mode. This temperature change rectifies the resistance of the metal thin film by the bolometric effect. So, optical characteristics of the proposed metasurface bolometer sensor, including quality factor (Q), sensitivity, and figure of merit (FoM) are calculated that Max sensitivity, FoM, and Q are 17.2 RIU-1, 530 and 434.5, respectively. Finally, we analytically simulate the temperature coefficient of resistance (TCR) in terms of wavelength and refractive index of analyte (na) that this resistance change can be monitored by an external electric model. The proposed plasmonic multilayer configuration is a very compact footprint structure that achieved high resistance sensitivity and FoM in comparison with any previous reports. This proposed thermal, optical, and electric plasmonic metasurface bolometer sensor can be used in different applications such as biophysics, biology, and environmental science.

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The formation mechanism of hexagonal Mo2C defects in CVD graphene grown on liquid copper

Physical Chemistry Chemical Physics ◽

10.1039/c9cp05618a ◽

2020 ◽

Vol 22 (4) ◽

pp. 2176-2180 ◽

Cited By ~ 3

Author(s):

Maryam Saeed ◽

Joseph D. Robson ◽

Ian A. Kinloch ◽

Brian Derby ◽

Chun-Da Liao ◽

...

Keyword(s):

Formation Mechanism ◽

Molybdenum Carbide ◽

Liquid Copper ◽

Cvd Graphene ◽

Graphene Films

Engineered defects in CVD graphene films are a challenge, and the growth of molybdenum carbide (Mo2C) with CVD graphene can hold great potential. The formation mechanism of Mo2C in CVD graphene is proposed.

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Simultaneous Optical Transmission Relaxation and Impedance Spectroscopy Measurements of Thin Film Oxygen Surface Exchange Kinetics

ECS Meeting Abstracts ◽

10.1149/ma2018-01/40/2321 ◽

2018 ◽

Keyword(s):

Thin Film ◽

Impedance Spectroscopy ◽

Optical Transmission ◽

Surface Exchange ◽

Exchange Kinetics ◽

Oxygen Surface Exchange ◽

Oxygen Surface

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Nanoscale graphene Hall sensors for high-resolution ambient magnetic imaging

Scientific Reports ◽

10.1038/s41598-019-50823-8 ◽

2019 ◽

Vol 9 (1) ◽

Cited By ~ 4

Author(s):

David Collomb ◽

Penglei Li ◽

Simon J. Bending

Keyword(s):

Room Temperature ◽

Chemical Vapour ◽

Theoretical Models ◽

Ambient Conditions ◽

Drive Current ◽

Cvd Graphene ◽

Magnetic Imaging ◽

Active Sensor ◽

Very High Spatial Resolution ◽

Hall Sensors

Abstract A major challenge to routine non-invasive, nanoscale magnetic imaging is the development of Hall sensors that are stable under ambient conditions and retain low minimum detectable fields down to nanoscale dimensions. To address these issues we have fabricated and characterised chemical vapour deposition (CVD) graphene Hall sensors with wire widths between 50 nm and 1500 nm, in order to exploit the high carrier mobility and tuneability of this material. The measured Hall voltage noise is in good agreement with theoretical models and we demonstrate that minimum detectable fields at fixed drive current are lowest in the vicinity of the charge neutrality point. Our best performing deep sub-micron sensors, based on a wire width of 85 nm, display the excellent room temperature resolution of 59 µT/√Hz at a dc drive current of 12 µA and measurement frequency of 531 Hz. We observe a weak increase in minimum detectable field as the active sensor area is reduced while the Hall offset field is largely independent of size. These figures-of-merit significantly surpass prior results on larger probes in competing materials systems, with considerable scope for further optimisation. Our results clearly demonstrate the feasibility of using CVD graphene to realise very high spatial resolution nanosensors for quantitative room temperature magnetic imaging.

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