Fabrication of 500 nm distributed Bragg reflector using Nb2O5-MgF2 multi-layer 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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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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Micro-zone optical measurements on GaN based nitride/air distributed Bragg reflector (DBR) mirrors made by focused ion beam milling

physica status solidi (c) ◽

10.1002/pssc.200404986 ◽

2004 ◽

Vol 1 (10) ◽

pp. 2450-2453 ◽

Cited By ~ 4

Author(s):

Qian Ren ◽

Bei Zhang ◽

Baoping Zhang ◽

Jun Xu ◽

Zhi Jian Yang ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Bragg Reflector ◽

Optical Measurements ◽

Distributed Bragg Reflector ◽

Focused Ion Beam Milling

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Focused Ion Beam Micromachining of GaN Photonic Devices

MRS Proceedings ◽

10.1557/proc-537-g10.7 ◽

1998 ◽

Vol 537 ◽

Cited By ~ 1

Author(s):

Irving Chyr ◽

A. J. Steckl

Keyword(s):

Focused Ion Beam ◽

Incident Angle ◽

Ion Beam ◽

Photonic Devices ◽

Substrate Material ◽

Bragg Reflector ◽

Distributed Bragg Reflector ◽

Effective Yield ◽

Dose Ranging ◽

Sputtering Yield

AbstractGa+ and Au+ focused ion beams (FIB) are used to micromachine GaN films. The GaN micromachining has been studied at energies from 30-90 keV, incident angle from 0-30°, and number of repetitive scans from 10 to 50 scans. Trenches milled in GaN have vertical and smooth side-walls and very smooth bottoms. The micromachining rate was found to be fairly independent of ion dose, ranging from 0.4 to 0.6 μm3/nC for Ga+ and I to 2 Pm3/nC for Au+. This translates into an effective yield of of 6-7 atoms/ion for Ga+ and 21-26 atoms/ion for Au+. This represents the highest direct FIB removal yield reported to date. We have also investigated the micromachining of GaN substrate material: c-face sapphire. Using FIB Ga+, sapphire has an effective yield of ∼2-2.5 atoms/ion, or approximately 1/3 of the GaN sputtering yield. For the materials investigated, we found the sputtering yield to be inversely proportional to the strength of the material chemical bond. We also describe the application of the FIB μmachining technique to the fabrication of small period Distributed Bragg Reflector (DBR) mirrors for a short cavity GaN laser structure.

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Enhanced-performance operation of InGaN MQW lasers with air/nitride-distributed Bragg reflector defined by focused ion beam etching

10.1117/12.429784 ◽

2001 ◽

Author(s):

Claudio Marinelli ◽

Laurence J. Sargent ◽

Michal Bordovsky ◽

Adrian Wonfor ◽

Judy M. Rorison ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Bragg Reflector ◽

Distributed Bragg Reflector ◽

Ion Beam Etching

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Focused Ion Beam Micromachining of GaN Photonic Devices

MRS Internet Journal of Nitride Semiconductor Research ◽

10.1557/s1092578300003604 ◽

1999 ◽

Vol 4 (S1) ◽

pp. 920-925

Author(s):

Irving Chyr ◽

A. J. Steckl

Keyword(s):

Focused Ion Beam ◽

Incident Angle ◽

Ion Beam ◽

Photonic Devices ◽

Substrate Material ◽

Bragg Reflector ◽

Distributed Bragg Reflector ◽

Effective Yield ◽

Dose Ranging ◽

Sputtering Yield

Ga+ and Au+ focused ion beams (FIB) are used to micromachine GaN films. The GaN micromachining has been studied at energies from 30-90 keV, incident angle from 0-30°, and number of repetitive scans from 10 to 50 scans. Trenches milled in GaN have vertical and smooth side-walls and very smooth bottoms. The micromachining rate was found to be fairly independent of ion dose, ranging from 0.4 to 0.6 µm3/nC for Ga+ and 1 to 2 µm3/nC for Au+. This translates into an effective yield of of 6-7 atoms/ion for Ga+ and 21-26 atoms/ion for Au+. This represents the highest direct FIB removal yield reported to date. We have also investigated the micromachining of GaN substrate material: c-face sapphire. Using FIB Ga+, sapphire has an effective yield of ∼2-2.5 atoms/ion, or approximately 1/3 of the GaN sputtering yield. For the materials investigated, we found the sputtering yield to be inversely proportional to the strength of the material chemical bond. We also describe the application of the FIB μmachining technique to the fabrication of small period Distributed Bragg Reflector (DBR) mirrors for a short cavity GaN laser structure.

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Distributed Bragg Reflector Laser With A Focused Ion Beam-implanted Grating

10.1109/leos.1988.689786 ◽

2005 ◽

Author(s):

M.C. Wu ◽

M.M. Boenke ◽

S. Wang ◽

W.M. Clark ◽

E.H. Stevens ◽

...

Keyword(s):

Focused Ion Beam ◽

Ion Beam ◽

Bragg Reflector ◽

Distributed Bragg Reflector

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Квантово-каскадные лазеры с распределенным брэгговским отражателем, сформированным методом ионно-лучевого травления

Письма в журнал технической физики ◽

10.21883/pjtf.2020.07.49211.18135 ◽

2020 ◽

Vol 46 (7) ◽

pp. 8

Author(s):

А.В. Бабичев ◽

Д.А. Пашнев ◽

А.Г. Гладышев ◽

Д.В. Денисов ◽

Г.В. Вознюк ◽

...

Keyword(s):

Focused Ion Beam ◽

Quantum Cascade Lasers ◽

Ion Beam ◽

Bragg Reflector ◽

Single Frequency ◽

Distributed Bragg Reflector ◽

Quantum Cascade ◽

Mode Suppression ◽

Lower Energy Level ◽

Cascade Lasers

Single-frequency lasing of quantum-cascade lasers with a distributed Bragg reflector formed by the focused ion beam milling technique in the layers of the upper cladding of the waveguide is demonstrated. The active region In0.53Ga0.47As/Al0.48In0.52As is formed based on the scheme with two-phonon lower energy level depopulation in the cascade. Single-frequency lasing at a temperature of 280 K corresponded to a radiation wavelength of 7.74 μm; the side mode suppression ratio (SMSR) was 24 dB.

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

10.21203/rs.3.rs-514602/v1 ◽

2021 ◽

Author(s):

Hsien-Wei Tseng ◽

Bo-Syuan. Chen ◽

You-Lin Wu ◽

Jing-Jenn Lin ◽

Cheng-Fu Yang

Keyword(s):

Transfer Matrix ◽

Focused Ion Beam ◽

Ion Beam ◽

Single Layer ◽

Approximate Equation ◽

Bilayer Film ◽

Bragg Reflectors ◽

Distributed Bragg Reflectors ◽

Glass Substrates ◽

Bilayer Films

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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