Effect of irradiation of silicon photodiode arrays for ITER radial x-ray camera investigated by measuring response and current–voltage characteristics

2021 ◽  
Vol 92 (4) ◽  
pp. 043301
Author(s):  
Chaozhi Li ◽  
Jinlong Zhao ◽  
Hongrui Cao ◽  
Liqun Hu ◽  
Kaiyun Chen ◽  
...  
Keyword(s):  
Silicon Photodiode ◽  
X Ray ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
Photodiode Arrays

Study on Schottky Diode Characteristics Improving by X-Ray Irradiation

2013 ◽  
Vol 717 ◽  
pp. 113-116
Author(s):  
Sani Klinsanit ◽  
Itsara Srithanachai ◽  
Surada Ueamanapong ◽  
Sunya Khunkhao ◽  
Budsara Nararug ◽  
...  
Keyword(s):  
Leakage Current ◽  
Schottky Diode ◽  
Room Temperature ◽  
The Other ◽  
Low Power Consumption ◽  
Initial Value ◽  
X Ray ◽  
Forward Current ◽  
Current Voltage ◽  
Current Voltage Characteristics

The effect of soft X-ray irradiation to the Schottky diode properties was analyzed in this paper. The built-in voltage, leakage current, and work function of Schottky diode were investigated. The current-voltage characteristics of the Schottky diode are measured at room temperature. After irradiation at 70 keV for 55 seconds the forward current and leakage current are increase slightly. On the other hand, the built-in voltage is decrease from the initial value about 0.12 V. Consequently, this method can cause the Schottky diode has low power consumption. The results show that soft X-ray can improve the characteristics of Schottky diode.

ELECTRONIC STRUCTURE AND CONDUCTIVITY OF HYDROCARBON FILMS OBTAINED IN PLASMA DISCHARGES OF TOKAMAK T-10

1970 ◽  
Vol 61 (11) ◽  
Author(s):  
Galina A. Sokolina ◽  
Igor I. Arkhipov ◽  
Nikolay Yu. Svechnikov ◽  
Sergey A. Grashin
Keyword(s):  
Activation Energy ◽  
Electronic Structure ◽  
Temperature Dependence ◽  
Direct Current ◽  
Plasma Discharges ◽  
X Ray ◽  
Hydrocarbon Films ◽  
Direct Current Conductivity ◽  
Current Voltage ◽  
Current Voltage Characteristics

Amorphous hydrocarbon films on silicon substrates obtained in the chamber of tokamak T-10 with space-bounded deuterium plasma by carbon diaphragms were studied. Using the methods of spectrophotometry, ellipsometry, X-ray photoemission spectroscopy and X-ray excited Auger electron spectroscopy, it was established that the refraction and absorption coefficients of films, as well as the parameters of the electronic structure such as the magnitude of the band gap, the fraction of sp2-hybridized carbon and the chemical composition of impurities depend on the characteristics of the discharge in the tokamak. It is shown that the deposited films refer to high-resistance dielectrics, and they can be classified by optical properties as hard or soft amorphous hydrocarbon films, depending on the type of the plasma discharge (pulse working discharge or long-term low-energy cleaning discharge). Wherein, the conductivity of hard films is less than that of soft films, which corresponds to a smaller fraction of sp2-states of carbon in these films and to a higher value of the band gap. The current-voltage characteristics and the temperature dependence of the direct current conductivity of hard and soft films were measured. It was shown that in the temperature range of 293–550 K, the conductivity is determined by the hopping conductivity mechanism over localized states near the Fermi level and the boundaries of the allowed bands. The hopping conductivity mechanism is also indicated by the power law obtained at room temperature at alternating current with a value of a power exponent close to 0.8. The measurement of the current-voltage characteristics and the temperature dependence of the conductivity of hard and soft films showed a significant difference in the activation energy of conductivity and the conductivity at an elevated temperature. The established dependences of the direct current conductivity and the activation energy value of the films on the discharge parameters can be used as diagnostic benchmarks of different types of plasma discharges in a tokamak. Data on the electrical conductivity of the films are analyzed within the framework of the concept of the electronic structure of amorphous non-crystalline materials.  

scholarly journals Optimization of soft X-ray tomography on the COMPASS tokamak

Nukleonika ◽  
2016 ◽  
Vol 61 (4) ◽  
pp. 403-408 ◽  
Author(s):  
Martin Imríšek ◽  
Jan Mlynář ◽  
Viktor Löffelmann ◽  
Vladimír Weinzettl ◽  
Tomáš Odstrčil ◽  
...  
Keyword(s):  
Cross Section ◽  
Diagnostic System ◽  
Numerical Differentiation ◽  
Pinhole Camera ◽  
Silicon Photodiode ◽  
Robust Solution ◽  
X Ray ◽  
Photodiode Arrays ◽  
Tomographic Inversions ◽  
Beryllium Foil

Abstract The COMPASS tokamak is equipped with the soft X-ray (SXR) diagnostic system based on silicon photodiode arrays shielded by a thin beryllium foil. The diagnostic is composed of two pinhole cameras having 35 channels each and one vertical pinhole camera with 20 channels, which was installed recently to improve tomographic inversions. Lines of sight of the SXR detectors cover almost complete poloidal cross section of the COMPASS vessel with a spatial resolution of 1-2 cm and temporal resolution of about 3 μs. Local emissivity is reconstructed via Tikhonov regularization constrained by minimum Fisher information that provides reliable and robust solution despite limited number of projections and ill-conditionality of this task. Improved border conditions and numerical differentiation matrices suppressing artifacts in reconstructed radiation were implemented in the code. Furthermore, a fast algorithm eliminating iterative processes was developed, and it is foreseen to be tested in real-time plasma control.

Effect of Systematic Changes of Ti and Hf Si-oxynitride Alloys by Nitrogen Incorporation as a Bond Constraint on Electrical and Material Properties

2007 ◽  
Vol 996 ◽  
Author(s):  
Sanghyun Lee ◽  
Gerry Lucovsky ◽  
L. B. Fleming ◽  
Jan Luning
Keyword(s):  
Photoelectron Spectroscopy ◽  
Oxide Thickness ◽  
Ternary Alloys ◽  
Flat Band ◽  
Compositional Dependence ◽  
X Ray ◽  
State Splitting ◽  
Current Voltage ◽  
Current Voltage Characteristics ◽  
X Ray Absorption

AbstractWe have investigated the effect of Si3N4 content in (Ti(Hf)O2)x(Si3N4)y(SiO2)1-x-y pseudo-ternary alloys by tracking systematic changes of electrical properties, including electrically active defects. Results from Soft x-ray photoelectron spectroscopy (SXPS) studies indicate no detectable hole traps for Ti/Hf Si oxynitrides with Si3N4 content >35%; these alloys have equal concentrations of Ti(Hf)O2 and SiO2, ~30-32%, and additionally are stable for annealing in Ar ambients to temperatures of 1100°C. Derivative near edge x-ray absorption spectroscopy (NEXAS) comparisons for the O K1 edges of TiO2 and optimized Ti Si oxynitride alloys provides a significantly reduced average crystal field d-state splitting from 1.9 to 1.6eV, as well as decreased electron trapping, and is correlated with a four-fold coordination of Ti in the Ti Si oxynitride alloys. The flat band voltage shift with varying frequency from 10 kHz to 1MHz in these alloys is less than 12 mV and the compositional dependence of current-voltage characteristics on Si3N4 composition results in the lowest leakage current at a Si3N4 content of ~40 % with the smallest equivalent oxide thickness (EOT) as well. Based on these studies, Transition Metal (TM) Si oxynitride alloys are anticipated to yield EOT <1 nm for scaled CMOS devises.

Rectifying characteristics and tunable magnetoresistance in heterojunctions of La0.9Hf0.1MnO3/0.05 wt.% Nb-doped SrTiO3

2017 ◽  
Vol 31 (25) ◽  
pp. 1745022 ◽  
Author(s):  
Yaping Qi ◽  
Xiangbo Liu ◽  
Hao Ni ◽  
Ming Zheng ◽  
Liping Chen ◽  
...  
Keyword(s):  
Band Structure ◽  
Pulsed Laser ◽  
Laser Deposition ◽  
Ferromagnetic Transition ◽  
Grown Film ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Current Voltage ◽  
Current Voltage Characteristics

La[Formula: see text]Hf[Formula: see text]MnO3 films were grown on 0.05 wt.% Nb-doped SrTiO3 substrates by pulsed laser deposition. X-ray diffraction measurements demonstrated that our samples were of good epitaxy and single-crystal. The temperature-dependent resistance has been investigated. It was observed that the as-grown film of La[Formula: see text]Hf[Formula: see text]MnO3 exhibited a typical paramagnetic-ferromagnetic transition. Heterojunctions of La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 exhibited-asymmetric current–voltage characteristics and a remarkable temperature-dependent rectifying behavior in a wide temperature range (from 40 K to 300 K). And the most remarkable observation of this work is the existence of a crossover from positive to negative magnetoresistance in the La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction as the temperature decreases. A temperature-dependent magnetoresistance was studied as well. The rectifying characteristics and tunable magnetoresistance of these heterojunctions may be attributed to band structure of La[Formula: see text]Hf[Formula: see text]MnO3/0.05 wt.% Nb-doped SrTiO3 heterojunction.

New Method for Improving the Electrical Characteristics of P-N Junction Diode

2011 ◽  
Vol 378-379 ◽  
pp. 606-609 ◽  
Author(s):  
Itsara Srithanachai ◽  
Surada Ueamanapong ◽  
Amporn Poyai ◽  
Surasak Niemcharoen
Keyword(s):  
Carrier Lifetime ◽  
Series Resistance ◽  
Device Performance ◽  
Electrical Characteristics ◽  
X Ray ◽  
Forward Current ◽  
Current Voltage ◽  
Capacitance Voltage ◽  
Current Voltage Characteristics ◽  
Junction Diode

This paper investigates the effect of soft X-ray irradiation various energy and times on P-N junction diodes. X-ray energy irradiated on P-N junction diode with 55 and 70 keV with various time in the range 5-50 sec. After irradiations were study on the current-voltage (I-V) characteristics and capacitance-voltage (C-V) characteristics. Leakages current after irradiated by X-ray are not change, while forward current are increase about 3 orders. The change of current-voltage characteristics can analyze by many parameter such as carrier lifetime and series resistance. Capacitance-voltage characteristics after irradiation are not change. The results show that soft X-ray technique can be improving performance of the P-N junction diodes. These techniques are importance to use for improving device performance in industry work.

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