Yag Single Crystals for Scintillators of Stem

1990 ◽  
Vol 48 (1) ◽  
pp. 166-167
Author(s):  
M. Hibino ◽  
K. Irie ◽  
R. Autrata ◽  
P. schauer
Keyword(s):  
Single Crystals ◽  
Yttrium Aluminum Garnet ◽  
Light Guide ◽  
Detection System ◽  
Polished Surface ◽  
Detective Quantum Efficiency ◽  
Backscattered Electrons ◽  
Electron Detection ◽  
Yttrium Aluminum ◽  
Phosphor Screens

Although powdered phosphor screens are usually used for scintillators of STEM, it has been found that the phosphor screen of appropriate thickness should be used depending on the accelerating voltage, in order to keep high detective quantum efficiency. 1 It has been also found that the variation in sensitivity, due to granularity of phosphor screens, makes the measurement of fine electron probe difficult and that the sensitivity reduces with electron irradiation specially at high voltages.In order to find out a preferable scintillator for STEM, single crystals of YAG (yttrium aluminum garnet), which are used for detecting secondary and backscattered electrons in SEM were investigated and compared with powdered phosphor screens, at the accelerating voltages of 100kV and 1 MV. A conventional electron detection system, consisting of scintillator, light guide and PMT (Hamamatsu Photonics R268) was used for measurements. Scintillators used are YAG single crystals of 1.0 to 3.2mm thicknesses (with surfaces matted for good interface to the light guide) and of 0.8mm thickness (with polished surface), and powdered P-46 phosphor screens of 0.07mm and 1.0mm thicknesses for 100kV and 1MV, respectively. Surfaces on electron-incidence side of all scintillators are coated with reflecting layers.

First-Surface Scintillator for Low Accelerating Voltage Scanning Electron Microscopy (SEM) Imaging

2018 ◽  
Vol 24 (5) ◽  
pp. 488-496
Author(s):  
Marian B. Tzolov ◽  
Nicholas C. Barbi ◽  
Christopher T. Bowser ◽  
Owen Healy
Keyword(s):  
Indium Tin Oxide ◽  
Yttrium Aluminum Garnet ◽  
Detection System ◽  
Conducting Layer ◽  
Backscattered Electrons ◽  
Electron Detection ◽  
Yttrium Aluminum ◽  
Low Energy Electrons ◽  
Spectrally Resolved

AbstractHighly luminescent thin films of zinc tungstate (ZT) have been deposited on top of conventional scintillators (Yttrium Aluminum Perovskite, Yttrium Aluminum Garnet) for electron detection in order to replace the need for a top conducting layer, such as indium tin oxide (ITO) or aluminum, which is non-scintillating and electron absorbing. Such conventional conducting layers serve the single purpose of eliminating electrical charge build-up on the scintillator. The ZT film also eliminates charging, which has been verified by measuring the Duane–Hunt limit and electron emission versus accelerating voltage. The luminescent nature of the ZT film ensures effective detection of low energy electrons from the very top surface of the structure ZT/scintillator, which we call “first-surfacescintillator”. The cathodoluminescence has been measured directly with a photodetector and spectrally resolved at different accelerating voltages. All results demonstrate the extended range of operation of the first-surface scintillator, while the conventional scintillators with a top ITO layer decline below 5 kV and have practically no output below 2 kV. Scintillators of different types were integrated in a detection system for backscattered electrons (BSE). The quality of the image at high accelerating voltages is comparable with the conventional scintillator and commercial BSE detector, while the image quality at 1 kV from the first-surface scintillator is superior.

Role of flux on synthesis of poly single crystals of Ce3+doped yttrium aluminum garnet

2016 ◽  
Vol 51 (3) ◽  
pp. 239-242 ◽  
Author(s):  
Zhen Song ◽  
Rui Zu ◽  
Xiaolang Liu ◽  
Lizhu He ◽  
Q.L. Liu
Keyword(s):  
Single Crystals ◽  
Yttrium Aluminum Garnet ◽  
Yttrium Aluminum

scholarly journals Сверхтонкое и квадрупольное взаимодействия в ЭПР изотопов -=SUP=-153-=/SUP=-Eu-=SUP=-2+-=/SUP=- и -=SUP=-151-=/SUP=-Eu-=SUP=-2+-=/SUP=- в иттрий-алюминиевом гранате

2021 ◽  
Vol 63 (9) ◽  
pp. 1394
Author(s):  
А.П. Потапов ◽  
В.А. Важенин ◽  
А.Г. Петросян ◽  
К.Л. Ованесян ◽  
Г.Р. Асатрян ◽  
...  
Keyword(s):  
Hyperfine Structure ◽  
Single Crystals ◽  
Yttrium Aluminum Garnet ◽  
Epr Spectrum ◽  
Quadrupole Interactions ◽  
Yttrium Aluminum

In specially grown single crystals of yttrium-aluminum garnet, the orthorhombic centers 153Eu2+ and 151Eu2+ were investigated. The parameters of hyperfine and quadrupole interactions, which describe the hyperfine structure of the EPR spectrum of both isotopes, are determined.

Micro-defects and luminescence of thulium-doped yttrium aluminum garnet single crystals

2021 ◽  
pp. 413568
Author(s):  
Fenhong Liu ◽  
Xiaojun Tan ◽  
Shoulei Xu ◽  
Xiangyu Wang ◽  
Bernard A. Goodman ◽  
...  
Keyword(s):  
Single Crystals ◽  
Yttrium Aluminum Garnet ◽  
Yttrium Aluminum

Optical studies of cerium doped yttrium aluminum garnet single crystals

1984 ◽  
Vol 44 (11) ◽  
pp. 1038-1040 ◽  
Author(s):  
C. M. Wong ◽  
S. R. Rotman ◽  
C. Warde
Keyword(s):  
Single Crystals ◽  
Yttrium Aluminum Garnet ◽  
Optical Studies ◽  
Yttrium Aluminum

scholarly journals YAG Laser Rod 3D Corrective Process Optimization through Tool Influent Function Shape Inspection

2020 ◽  
Vol 10 (22) ◽  
pp. 8194
Author(s):  
Frantisek Prochaska ◽  
Karel Nejezchleb ◽  
Jiri Benes ◽  
Ondrej Matousek ◽  
David Tomka
Keyword(s):  
Influence Function ◽  
Yttrium Aluminum Garnet ◽  
Solid State Laser ◽  
Polished Surface ◽  
Elastic Membrane ◽  
Tool Influence Function ◽  
Yttrium Aluminum ◽  
Optical Production ◽  
Shape Inspection

Due to the increasing demands on the quality of solid-state laser active media production based on yttrium aluminum garnet Y3Al5O12 in the form of rods with precisely machined faces, the possibilities of applying subaperture 3D corrective polishing in this segment of optical production were studied. For the considered laser rod diameters of up to 10 mm, the corrective process had to be optimized to achieve a stable, suitably shaped tool influence function at the full width at half maximum of approximately 1.5 mm, enabling 3D shape corrections with sufficient lateral resolution. For this purpose, a number of experiments were performed using both tools based on a flexible elastic membrane inflated by compressed air and tools with a viscoelastic head, and the effect of the tool-polished surface interaction was studied and analyzed.

Influence of Transition Metals on The Defect and Optical Properties of Yttrium Aluminum Garnet

1985 ◽  
Vol 60 ◽  
Author(s):  
S. R. Rotman ◽  
H. L. Tuller
Keyword(s):  
Optical Properties ◽  
Transition Metals ◽  
Single Crystals ◽  
Defect Structure ◽  
Yttrium Aluminum Garnet ◽  
Defect Formation ◽  
Electrical And Optical Properties ◽  
Yttrium Aluminum ◽  
Energy States ◽  
And Migration

AbstractThe electrical and optical properties of single crystals of Ni, Ni + Zr, and Fe doped Y3Al5O12(YAG) were studied as a function of temperature, atmosphere and composition. The often dramatic changes in properties observed for these materials are interpreted in terms of the underlying defect structure of these materials. Defect formation and migration energies are derived as well as the position of energy states within the gap.

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