Comparison of Measurement and Electromagnetic Overall Transfer Matrix Simulation Results of MgF 2 -Nb 2 O 5 Distributed Bragg Reflectors with Different Layers

Abstract In this study, glasses were used as substrates and an e-beam was used the method to deposit MgF2 and Nb2O5 single-layer films, and the optical properties, including extinction coefficients (k values) and refractive indices (n values), were measured by using the light wavelength as variable. The equation d = λ/(4n) was used to calculate the thickness (d) of 1/4 wavelength (λ) for each layer of the MgF2-Nb2O5 bilayer films in distributed Bragg reflectors (DBRs) with a designed reflective wavelength at blue light (~450nm). Each MgF2-Nb2O5 bilayer film was called a period, and the glass substrates were used to deposit the films with two, four, and six periods for fabricating the DBRs. The field emission scanning electron microscope equipped with a focused ion beam was used to measure the thickness of each MgF2-Nb2O5 layer in the DBRs with different periods. The measured maximum reflective ratios were compared with Sheppard’s approximate equation, which calculates only the maximum reflective ratio at a specific wavelength. An overall transfer matrix was investigated to calculate the reflective spectra by incorporating the variable n values and thicknesses of the MgF2-Nb2O5 films in each layer. We show that the measured results of the fabricated DBRs matched the results simulated using Sheppard’s approximate equation and the overall transfer matrix.

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Fabrication of 500 nm distributed Bragg reflector using Nb2O5-MgF2 multi-layer films

Modern Physics Letters B ◽

10.1142/s0217984921400017 ◽

2020 ◽

pp. 2140001

Author(s):

Yong Du ◽

Bo-Syuan Chen ◽

Jing-Jenn Lin ◽

Hsien-Wei Tseng ◽

You-Lin Wu ◽

...

Keyword(s):

Wavelength Range ◽

Focused Ion Beam ◽

Ion Beam ◽

Green Light ◽

Single Layer ◽

Bragg Reflector ◽

Index Formula ◽

Distributed Bragg Reflector ◽

Central Wavelength ◽

Bilayer Films

At first, we use an [Formula: see text] analyzer to measure the optical properties (including refractive index [Formula: see text] and extinction coefficient [Formula: see text]) of MgF2 and Nb2O5 single-layer films, in a wavelength range of 200–1700 nm for MgF2 film and in a wavelength range of 350–1500 nm for Nb2O5 film. After the refractive indexes of MgF2 and Nb2O5 single-layer films are measured, we use the measured results to calculate the needed thicknesses of the quarter-wave (1/4 wavelength) MgF2 and Nb2O5 films for the designed green-light (500 nm) distributed Bragg reflectors (DBRs). After that, an E-beam is used to deposit the MgF2-Nb2O5 bilayer films (called as one period) with different periods (two, four, and six periods are deposited in this study) on glass substrates to fabricate the DBRs with a central wavelength of 500 nm. Then we use the field emission scanning electron microscopy (FESEM) to observe the surface images of Nb2O5 films on the different periods of MgF2-Nb2O5 bilayer films. The important novelty is that we use a Focused Ion Beam (FIB) to prepare the samples for the observations of the cross-sections of MgF2-Nb2O5 bilayer films, and those results can be sued to confirm the thicknesses of the bilayer films with different periods. We also compare the reflective ratio of the fabricated DBRs at the designed central wavelength with those calculated values by using the equation investigated by Sheppard. We find that the measured reflective ratios of the fabricated DBRs meet the calculated results obtained from Sheppard’s equation.

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An Study of Influence of Imperfections on the Delamination of Diamond-Like Carbon Films

MRS Proceedings ◽

10.1557/proc-719-f8.36 ◽

2002 ◽

Vol 719 ◽

Author(s):

Myoung-Woon Moon ◽

Kyang-Ryel Lee ◽

Jin-Won Chung ◽

Kyu Hwan Oh

Keyword(s):

Cross Sections ◽

Focused Ion Beam ◽

Imaging System ◽

Ion Beam ◽

Carbon Films ◽

Diamond Like Carbon ◽

Glass Substrates ◽

Atomic Force ◽

Initiation And Propagation

AbstractThe role of imperfections on the initiation and propagation of interface delaminations in compressed thin films has been analyzed using experiments with diamond-like carbon (DLC) films deposited onto glass substrates. The surface topologies and interface separations have been characterized by using the Atomic Force Microscope (AFM) and the Focused Ion Beam (FIB) imaging system. The lengths and amplitudes of numerous imperfections have been measured by AFM and the interface separations characterized on cross sections made with the FIB. Chemical analysis of several sites, performed using Auger Electron Spectroscopy (AES), has revealed the origin of the imperfections. The incidence of buckles has been correlated with the imperfection length.

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Investigations of Al2O3–Nb2O5 bi-layer Bragg reflector investigations for blue and green lights

Functional Materials Letters ◽

10.1142/s1793604720510431 ◽

2020 ◽

Vol 13 (08) ◽

pp. 2051043

Author(s):

Shu-Min You ◽

Cheng-Yang You ◽

Jing-Jenn Lin ◽

Cheng-Fu Yang

Keyword(s):

Green Light ◽

Single Layer ◽

Bragg Reflector ◽

Refractive Indices ◽

Bragg Reflectors ◽

Full Width ◽

Central Wavelength ◽

Glass Substrates ◽

Reflectance Ratio

At first, the single-layer Al2O3 and Nb2O5 films were deposited to find their refractive indices. After the indices of the single-layer Al2O3 and Nb2O5 films were measured, the thickness of 1/4 wavelength ([Formula: see text] for each layer of the Al2O3–Nb2O5 bi-layer Bragg reflectors of blue (450-nm) and green (550-nm) lights could be obtained. E-beam was used to deposit the bi-layer Al2O3–Nb2O films (called as one period) with two, four, and six periods on glass substrates to fabricate the Bragg reflectors of blue and green lights. The measured results had proven that the reflectance ratio increased and the bandwidth and full-width at half-depth (FWHD) decreased with the increase of number of periods. The measured results had also proven that as the designed central wavelength increased (changed from blue to green light) and same periods were deposited, the reflectance ratio decreased and the bandwidth and FWHD values increased.

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Electrical characteristics, stability, electromigration, Joule heating, and reliability aspect of focused ion beam fabricated gold and copper nanobar interconnects on SiO2 and glass substrates

Journal of Vacuum Science & Technology B Nanotechnology and Microelectronics Materials Processing Measurement and Phenomena ◽

10.1116/6.0000514 ◽

2020 ◽

Vol 38 (6) ◽

pp. 062805

Author(s):

Abhishek Kumar Singh ◽

Jitendra Kumar

Keyword(s):

Joule Heating ◽

Focused Ion Beam ◽

Ion Beam ◽

Electrical Characteristics ◽

Glass Substrates

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Formulation and characterization of bilayer films based on Brea gum and Pectin

BRAZILIAN JOURNAL OF FOOD TECHNOLOGY ◽

10.1590/1981-6723.21317 ◽

2018 ◽

Vol 21 (0) ◽

Author(s):

Aníbal Marcelo Slavutsky ◽

Jimena Elizabeth Gamboni ◽

María Alejandra Bertuzzi

Keyword(s):

Water Vapour ◽

Single Layer ◽

Controlled Drug Release ◽

Water Vapour Permeability ◽

Bilayer Film ◽

Vapour Permeability ◽

Bilayer Films ◽

Film Forming ◽

Differential Properties

Abstract The formulation of bilayer films is a strategy aimed at combining the advantages and properties of different film-forming materials. Bilayer films based on pectin and brea gum were formulated and their functional properties studied and compared with those presented by single layer films of each component. The micrographs and surface properties confirmed that the bilayer films can maintain their identity and prevent delamination. The mechanical properties of the films depended on the characteristics of the polymers and their interactions, and the bilayer films showed prevalence of the brea gum properties. The brea gum films showed high solubility that influenced the bilayer film solubility. The water vapour permeability of the bilayer films was dependent on the material that was exposed to the side where desorption occurred. The bilayer films presented lower water vapour permeability than the brea gum films but higher than that of pectin films of similar thicknesses. The differential properties of each layer of bilayer films make them potentially interesting for controlled drug release.

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Graphene crystal growth by thermal precipitation of focused ion beam induced deposition of carbon precursor via patterned-iron thin layers

Nanofabrication ◽

10.2478/nanofab-2014-0001 ◽

2014 ◽

Vol 1 (1) ◽

Author(s):

Gemma Rius ◽

Francesc Perez-Murano ◽

Masamichi Yoshimura

Keyword(s):

Thermal Treatment ◽

Focused Ion Beam ◽

Ion Beam ◽

Single Layer ◽

Device Fabrication ◽

Thin Layers ◽

High Temperature Treatment ◽

Iron Carbides ◽

Complete Wetting ◽

Graphene Growth

AbstractRecently, relevant advances on graphene as a building block of integrated circuits (ICs) have been demonstrated. Graphene growth and device fabrication related processing has been steadily and intensively powered due to commercial interest; however, there are many challenges associated with the incorporation of graphene into commercial applications which includes challenges associated with the synthesis of this material. Specifically, the controlled deposition of single layer large single crystal graphene on arbitrary supports, is particularly challenging. Previously, we have reported the first demonstration of the transformation of focused ion beam induced deposition of carbon (FIBID-C) into patterned graphitic layers by metal-assisted thermal treatment (Ni foils). In this present work, we continue exploiting the FIBID-C approach as a route for graphene deposition. Here, thin patterned Fe layers are used for the catalysis of graphenization and graphitization. We demonstrate the formation of high quality single and few layer graphene, which evidences, the possibility of using Fe as a catalyst for graphene deposition. The mechanism is understood as the minute precipitation of atomic carbon after supersaturation of some iron carbides formed under a high temperature treatment. As a consequence of the complete wetting of FIBID-C and patterned Fe layers, which enable graphene growth, the as-deposited patterns do not preserve their original shape after the thermal treatment

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Fundamental Criteria for the Propagation of Telephone Cord Buckles Beneath DLC Films on Glass Substrates

MRS Proceedings ◽

10.1557/proc-695-l2.4.1 ◽

2001 ◽

Vol 695 ◽

Author(s):

Myoung-Woon Moon ◽

Kyang-Ryel Lee ◽

Jin-Won Chung ◽

And Kyu Hwan Oh

Keyword(s):

Focused Ion Beam ◽

Imaging System ◽

Ion Beam ◽

Repeat Unit ◽

Carbon Films ◽

Local Mode ◽

Force Microscopy ◽

Glass Substrates ◽

Atomic Force ◽

Insight Into

ABSTRACTThe topology of telephone cord buckles that form beneath compressed diamond-like carbon films (DLC) on glass substrates has been characterized with Atomic Force Microscopy (AFM) and with the Focused Ion Beam (FIB). Using AFM with 2nm resolution, the wavelength and amplitude of the buckles and their profiles have been measured. It has been found that, within each wavelength, the profile has symmetric and asymmetric segments. These changes have been related to differences in local mode mixity around the periphery of each repeat unit along the buckle, resulting in a fundamental rationale for the factors governing the wavelength. Sections made through various segments of the buckle by using the FIB imaging system result in local changes in the shape and size of the buckles that provide further insight into the buckle propagation criterion.

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