scholarly journals Влияние режима отжига на свойства терагерцевой фотопроводящей антенны на основе LT-GaAs

2018 ◽  
Vol 44 (2) ◽  
pp. 11
Author(s):  
С.А. Номоев ◽  
И.С. Васильевский ◽  
А.Н. Виниченко ◽  
К.И. Козловский ◽  
А.А. Чистяков ◽  
...  
Keyword(s):  
Gallium Arsenide ◽  
Film Surface ◽  
Thz Spectroscopy ◽  
Photoconductive Antennas ◽  
Annealing Temperatures ◽  
Gaas Films ◽  
Postgrowth Annealing ◽  
Optimum Interval ◽  
Reduced Temperature ◽  
Lt Gaas

AbstractLow-temperature gallium arsenide (LT-GaAs) films were grown by the method of molecularbeam epitaxy (MBE) at a reduced temperature (230°C) on GaAs(100) substrates and subjected to postgrowth annealing in various regimes. Photoconductive antennas (PCAs) with flag geometry formed on the film surface were characterized by terahertz (THz) response power at various bias voltages. The method of THz spectroscopy was used to study the characteristics of PCAs based on LT-GaAs films annealed in various regimes and the optimum interval of postgrowth annealing temperatures (670–720°C) was established.

The Research for Approaches to Increase Power of the Compact THz Emitters Based on Low-Temperature Gallium Arsenide Heterostructures

2020 ◽  
Vol 310 ◽  
pp. 101-108
Author(s):  
Sergey Nomoev ◽  
Ivan Vasilevskii ◽  
Alexander Vinichenko
Keyword(s):  
Gallium Arsenide ◽  
Low Temperature ◽  
Drift Diffusion ◽  
Photoconductive Antennas ◽  
Poisson Equations ◽  
Full Wave ◽  
Second Period ◽  
Optical Behavior ◽  
Thz Antenna ◽  
Lt Gaas

The design and technological conditions for the manufacture of photoconductive antennas based on low-temperature gallium arsenide (LT-GaAs) have been developed. The optimized photoconductive THz antenna is made based on LT-GaAs with the flag geometry of the contacts and with the interdigitated structure including metal closing through the dielectric of each second period. LT-GaAs samples were obtained by molecular beam epitaxy at temperatures of 210 °C, 230 °C, 240 °C on GaAs substrates (100). Dark and photocurrent were measured depending on the bias voltage of the LT-GaAs heterostructure at the EP6 probe station. Full wave finite element method solver has been used to investigate the proposed plasmon PCA electrical and optical behavior by combining the Maxwell's wave equation with the drift-diffusion/Poisson equations.

Terahertz Emission Enhancement of Gallium Arsenide-based Photoconductive Antennas by Silicon Nanowire Coating

2021 ◽  
pp. 1-1
Author(s):  
Neil Irvin Cabello ◽  
Alexander De Los Reyes ◽  
Vladimir Sarmiento ◽  
John Paul Ferrolino ◽  
Victor DC Andres Vistro ◽  
...  
Keyword(s):  
Gallium Arsenide ◽  
Silicon Nanowire ◽  
Terahertz Emission ◽  
Photoconductive Antennas ◽  
Emission Enhancement

scholarly journals Impact of LT-GaAs layers on crystalline properties of the epitaxial GaAs films grown by MBE on Si substrates

2016 ◽  
Vol 741 ◽  
pp. 012020 ◽  
Author(s):  
M O Petrushkov ◽  
M A Putyato ◽  
A K Gutakovsky ◽  
V V Preobrazhenskii ◽  
I D Loshkarev ◽  
...  
Keyword(s):  
Epitaxial Gaas ◽  
Si Substrates ◽  
Gaas Films ◽  
Lt Gaas

ArF Excimer Laser-Induced Epitaxial Growth of GaAs Films on Si

1988 ◽  
Vol 116 ◽  
Author(s):  
Shirley S. Chu ◽  
T. L. Cpu ◽  
C. L. Chang
Keyword(s):  
Gallium Arsenide ◽  
Substrate Temperature ◽  
Excimer Laser ◽  
Substrate Surface ◽  
Molar Ratio ◽  
Structural Perfection ◽  
Lower Growth ◽  
Si Substrates ◽  
Gaas Films ◽  
Arf Excimer Laser

AbstractEpitaxial gallium arsenide films have been deposited on single crystalline GaAs substrates of {100} orientation and Si substrates of 3° off the {100} orientation by ArF excimer laser-induced metalorganic chemical vapor deposition. The important process parameters include the cleanliness of the substrate surface, substrate temperature, the composition, flow rate, and pressure of the reaction mixture, and the pulse energy and pulse rate of the laser. Particular attention was directed to the in-situ cleaning of the substrate surface prior to the deposition process. Homoepitaxial gallium arsenide films of good structural perfection have been deposited at 425°- 500 ° C and their single crystallinity has been confirmed by transmission electron microscopy. The carrier concentration decreases with increasing AsH3/(CH3)3 Ga molar ratio and with decreasing substrate temperature. Lower growth rate during the initial stage of deposition is necessary to obtain heteroepitaxial gallium arsenide films on Si with good structural perfection. The TEM examination of GaAs films of 0.15–0.2 µm thickness deposited on Si substrates at 500 °C has shown that stacking faults were present in the GaAs films; however, there is no apparent threading dislocations in the surface region of the thin GaAs film.

Ferroelectric Properties of Polyvinylidenefluoride-Trifluoroethylene (PVDF-TrFE) Annealed Thin Film

2014 ◽  
Vol 879 ◽  
pp. 1-6
Author(s):  
Mohamad Hafiz Mohd Wahid ◽  
Rozana Mohd Dahan ◽  
Siti Zaleha Sa'ad ◽  
Adillah Nurashikin Arshad ◽  
Muhamad Naiman Sarip ◽  
...  
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Annealing Temperature ◽  
Ferroelectric Properties ◽  
Film Surface ◽  
Ferroelectric Crystal ◽  
Annealing Temperatures ◽  
Morphological Studies ◽  
High Possibility ◽  
Scanning Electron

The annealing temperature for 250nm PVDF-TrFE (70:30 mol %) spin coated thin films were varied at solvent evaporation (Ts = 79°C), Curies transition (Tc= 113°C) till melting temperature (Tm = 154°C). From the XRD measurement, there was an improvement in the crystallinity of the annealed films, consistent with the increased in the annealing temperatures. Morphological studies of the annealed PVDF-TrFE thin films as observed with Field Emission Scanning Electron Microscope (FESEM) (100k magnification), showed enhanced development of elongated crystallite structures better known as ferroelectric crystal. However, the AN160 thin film showed fibrous-like structure with appearance of nanoscale separations, which suggested to posed high possibility of defects. Ferroelectric characterization indicated an improvement in the remnant polarization of annealed PVDF-TrFE thin films with the exception to AN160 in which leakage of current was inevitable due to the presence of cracks on the film surface.

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