Light-induced Stability of Layered Amorphous Hydrogenated Silicon Grown with Alternating Substrate Temperature

1996 ◽  
Vol 420 ◽  
Author(s):  
Jong-Hwan Yoona ◽  
Czang-Ho Lee
Keyword(s):  
Substrate Temperature ◽  
Defect Density ◽  
Single Layer ◽  
Light Illumination ◽  
Hydrogenated Silicon ◽  
Layer Film ◽  
Amorphous Hydrogenated Silicon ◽  
Improved Stability ◽  
Single Layer Film ◽  
Hydrogenated Amorphous

AbstractWe present the results of studies on the light-induced stability of undoped layered hydrogenated amorphous silicon films grown with alternating substrate temperature between optimal and non optimal temperatures for device-quality films. Compared to the single layer films grown at optimal substrate temperature, the layered films show improved stability in the lightinduced state. Under intense light illumination of 3 W/cm2, the steady-state defect density of the layered film reached a saturation of 2×1016 cm−3, while the single layer film saturates at about 6×1016 cm−3. It is found that in the completely degraded state the photoconductivity in the layered film is also improved by a factor of two compared to the single layer film.

The Effect of Deposition Procedure on the Conductivity of Hydrogenated Amorphous Silicon Multilayer Films.

1986 ◽  
Vol 70 ◽  
Author(s):  
G. Moddel ◽  
F.-C. Su ◽  
P. E. Vanier
Keyword(s):  
Defect Density ◽  
Multilayer Films ◽  
Oxide Interface ◽  
Hydrogenated Silicon ◽  
Plasma Enhanced Cvd ◽  
Amorphous Hydrogenated Silicon ◽  
Defective Layer ◽  
State Densities ◽  
Continuous Deposition ◽  
Hydrogenated Amorphous

ABSTRACTThe conductivity of multilayer P-doped amorphous hydrogenated silicon (a-Si:H) thin films is measured for films prepared with different, deposition procedures. Multilayer films are deposited by plasma enhanced CVD following a procedure in which the plasma is extinguished and the deposition chamber is filled with air or argon after the deposition of each layer. These films are compared to films grown in continuous deposition runs. The technique provides a direct means to determine the effects of continuous versus interrupted deposition and to analyze oxide interface and bulk gap state densities. Exposing the layers to air between depositions produces deleterious effects whereas the effect of argon exposure are slight. Literature values for the density of states in oxidized a-Si:H are used to provide evidence for a defective layer in very thin P-doped a-Si:H having a defect density of over 1013 cm−2 eV−1 approximately 0.3 eV below the transport level.

scholarly journals On the Effect of Substrate Temperature on a-Si:H Deposition Using an Expanding Thermal Plasma

1996 ◽  
Vol 420 ◽  
Author(s):  
R. J. Severens ◽  
M. C. M. Van De Sanden ◽  
H. J. M. Verhoeven ◽  
J. Bastiaanssen ◽  
D. C. Schram
Keyword(s):  
Growth Rate ◽  
Substrate Temperature ◽  
Urbach Energy ◽  
Hydrogen Plasma ◽  
Hydrogen Abstraction ◽  
Plasma Jet ◽  
Hydrogenated Silicon ◽  
Amorphous Hydrogenated Silicon ◽  
Simple Kinetic Model ◽  
S Deposition

AbstractFast (7 nm/s) deposition of amorphous hydrogenated silicon with a midgap density of states less than 1016 cm-3 and an Urbach energy of 50 meV has been achieved using a remote argon/hydrogen plasma. The plasma is generated in a dc thermal arc (0.5 bar, 5 kW) and expands into a low pressure chamber (20 Pa) thus creating a plasma jet with a typical flow velocity of 103 m/s. Pure silane is injected into the jet immediately after the nozzle, in a typical flow mixture of Ar:H2:SiH4=55:10:10 scc/s. As the electron temperature in the recombining plasma is low (typ. 0.3 eV), silane radicals are thought to be produced mainly by hydrogen abstraction.Material quality in terms of refractive index, conductivity, microstructure parameter and optical bandgap was found to increase monotonously with substrate temperature, even up to 350 °C; for practically all low growth rate deposition schemes an optimum around 250 °C is observed. It will be argued that this behavior is consistent with a simple kinetic model involving physisorption and hopping, growth on dangling bonds and thermal desorption of hydrogen.

Effect of the Substrate Temperature on the Transition from Amorphous to Microcrystalline Silicon with High Hydrogen Dilution

2013 ◽  
Vol 773 ◽  
pp. 520-523
Author(s):  
Ming Liang Zhang ◽  
Hui Dong Yang ◽  
Kai Zhao Yang
Keyword(s):  
Substrate Temperature ◽  
Volume Fraction ◽  
Chemical Vapor ◽  
Silicon Films ◽  
Microcrystalline Silicon ◽  
High Hydrogen ◽  
Hydrogenated Silicon ◽  
Glass Substrates ◽  
Amorphous Hydrogenated Silicon ◽  
The Stability

Transition films of amorphous hydrogenated silicon (a-Si:H) to microcrystalline silicon (μc-Si:H) have attracted much attention due to the stability, high overall quality for solar cells configuration. Hydrogenated amorphous and microcrystalline silicon films were deposited on glass substrates by a conventional plasma enhanced chemical vapor deposition (PEVCD) varying the substrate temperature from 275 to 350 °C. A silane concentration of 4% and a total flow rate of 100 sccm were used at a gas pressure of 267 Pa. The film thicknesses of the prepared samples were between 700 and 900 nm estimated from the optical transmission spectra. The deposition rates were between 0.2 and 0.3 nm/s. The phase composition of the deposited silicon films were investigated by Raman spectroscopy. The transition from amorphous to microcrystalline silicon was found at the higher temperatures. The crystallization process of the amorphous silicon can be affected by the substrate temperature. A narrow structural transition region was observed from the changes of the crystalline volume fraction. The dark electrical conductivity of the silicon films increased as the substrate temperature increasing.

Creation of High-Density and Low-Defect Single-Layer Film of Magnetic Nanoparticles by the Method of Interfacial Molecular Films

Langmuir ◽  
2015 ◽  
Vol 31 (10) ◽  
pp. 3254-3261 ◽  
Author(s):  
Atsuhiro Fujimori ◽  
Kyohei Ohmura ◽  
Nanami Honda ◽  
Koichi Kakizaki
Keyword(s):  
Magnetic Nanoparticles ◽  
Single Layer ◽  
High Density ◽  
Molecular Films ◽  
Layer Film ◽  
Single Layer Film

Interaction between Water Molecules and an Al2 – xO3 – y Single-Layer Film

2020 ◽  
Vol 14 (3) ◽  
pp. 617-620
Author(s):  
T. T. Magkoev ◽  
G. S. Grigorkina ◽  
V. B. Zaalishvili ◽  
O. G. Burdzieva ◽  
E. N. Kozyrev ◽  
...  
Keyword(s):  
Single Layer ◽  
Water Molecules ◽  
Layer Film ◽  
Single Layer Film

Reliable Organic Nonvolatile Memory Device Using a Polyfluorene-Derivative Single-Layer Film

2008 ◽  
Vol 29 (8) ◽  
pp. 852-855 ◽  
Author(s):  
Tae-Wook Kim ◽  
Seung-Hwan Oh ◽  
Hyejung Choi ◽  
Gunuk Wang ◽  
Hyunsang Hwang ◽  
...  
Keyword(s):  
Nonvolatile Memory ◽  
Single Layer ◽  
Memory Device ◽  
Layer Film ◽  
Nonvolatile Memory Device ◽  
Single Layer Film
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