Aluminum-Induced Crystallization of PECVD Amorphous Silicon

2004 ◽  
Vol 808 ◽  
Author(s):  
Kenneth Jenq ◽  
Shawn S. Chang ◽  
Yaguang Lian ◽  
Grant Z. Pan ◽  
Yahya Rahmat-Samii
Keyword(s):  
Amorphous Silicon ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Electron Beam Evaporation ◽  
Kinetics Analysis ◽  
Conventional Furnace ◽  
Through Diffusion ◽  
Induced Crystallization ◽  
Aluminum Induced Crystallization

ABSTRACTAluminum-induced crystallization (AIC) of amorphous silicon (a-Si) in a conventional furnace with N2 protection has been studied at reaction temperatures ranging from 200 to 500°C by using optical microscopy, and transmission and scanning electron microscopy. The a-Si and Al layers were deposited with plasma-enhanced chemical vapor deposition (PECVD) and electron beam evaporation, respectively. The structures in the study are Al/a-Si and a-Si/Al on Si or glass wafers coated with 3000 Å PECVD SiO2. It was found that Al induces crystallization of a-Si for both Al/a-Si and a-Si/Al structures by exchanging positions of Al and Si layer through diffusion of Si into Al and the grain size of crystallized Si (c-Si) increases with the decrease of AIC temperature. AIC for Al/a-Si structures starts at a temperature as low as 200°C, which is 100°C lower than that for a-Si/Al structures. Kinetics analysis found that the activation energies are 1.76 eV and 1.65 eV for both Al/a-Si and a-Si/Al structures, respectively. The quality of AIC c-Si depends on the order, thickness and thickness ratio of a-Si to Al. Microstructural observations indicated that the c-Si for Al/a-Si structures is better and more suitable for use in fabrication of thin film transistors (TFTs) than that for a-Si/Al structures.

Effects of Power Density and Thickness On Aluminum-Induced Crystallization of PECVD Amorphous Silicon

2007 ◽  
Vol 989 ◽  
Author(s):  
Kendrick S Hsu ◽  
Jeremy Ou-Yang ◽  
Li P. Ren ◽  
Grant Z. Pan
Keyword(s):  
Thin Films ◽  
Amorphous Silicon ◽  
Power Density ◽  
Reaction Temperature ◽  
Chemical Vapor ◽  
X Ray Diffraction ◽  
Transmission Electron ◽  
Temperature Scanning ◽  
Induced Crystallization ◽  
Aluminum Induced Crystallization

AbstractThe effect of power density and thickness on aluminum-induced crystallization (AIC) of amorphous silicon (a-Si) formed with plasma enhanced chemical vapor deposition (PECVD) was studied by using N2-protected conventional furnace reaction and optical microscopy. With the deposition power density ranging from 0.05 to 1.00 W/cm2 and the thickness from 500 to 5000Å, it was found that a low power density as well as a large a-Si thickness could result in a decrease of activation energy and therefore a significant reduction of the AIC reaction temperature. Scanning and transmission electron microscopy and X-ray diffraction were used to check the crystallinity and quality of the AIC thin films. High quality polysilicon thin films were achieved at an AIC reaction temperature as low as 120°C.

New Results on the Microstructure of Amorphous Silicon as Observed by Internal Friction

1997 ◽  
Vol 467 ◽  
Author(s):  
R. S. Crandall ◽  
A. H. Mahan ◽  
E. Iwaniczko ◽  
K. M. Jones ◽  
X. Liu ◽  
...  
Keyword(s):  
Internal Friction ◽  
Amorphous Silicon ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Amorphous Solid ◽  
Amorphous Solids ◽  
Electron Beam Evaporation ◽  
Hot Wire ◽  
Si Films ◽  
Hydrogenated Amorphous

ABSTRACTWe have measured the low temperature internal friction (Q−1) of amorphous silicon (a-Si) films. Electron-beam evaporation leads to the well-known temperature-independent plateau common to all amorphous solids. For hydrogenated amorphous silicon (a-Si:H) with about 1 at.% H produced by hot wire chemical vapor deposition, however, the value of is over two hundred times smaller than for e-beam a-Si. This is the first observation of an amorphous solid without any significant low energy excitations. This finding offers the opportunity to study amorphous solids containing controlled densities of tunneling defects, and thus to explore their nature.

Comparison of Characteristics of Rapid Thermal and Microwave Annealed Amorphous Silicon Thin Films Prepared by Electron Beam Evaporation and Low Pressure Chemical Vapor Deposition

2013 ◽  
Vol 663 ◽  
pp. 372-376
Author(s):  
Chi Hua Hsieh ◽  
Li Te Tsou ◽  
Sheng Hao Chen ◽  
Huai Yi Chen ◽  
Yao Jen Lee ◽  
...  
Keyword(s):  
Electron Beam ◽  
Chemical Vapor Deposition ◽  
Amorphous Silicon ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Electron Beam Evaporation ◽  
Silicon Thin Films ◽  
Pressure Chemical ◽  
Si Films ◽  
The Cost

In this study we use chemical and physical vapor depositions to fabricate amorphous silicon (a-Si) films. We also use traditional rapid thermal annealing (RTA) and advanced microwave annealing (MWA) to activate or crystallize a-Si films and then observe their sheet resistances and crystallization. We discovered, although the cost of films fabricated by electron beam (e-beam) evaporation is relatively lower than by chemical vapor deposition (CVD), the effects of the former method are poorer whether in sheet resistance or film crystallization. In addition, only at the doping layer prepared by CVD can film crystallization degree produced by MWA match RTA.

scholarly journals Study of deposition parameters and growth kinetics of ZnO deposited by aerosol assisted chemical vapor deposition

RSC Advances ◽  
2021 ◽  
Vol 11 (30) ◽  
pp. 18493-18499
Author(s):  
Sergio Sánchez-Martín ◽  
S. M. Olaizola ◽  
E. Castaño ◽  
E. Urionabarrenetxea ◽  
G. G. Mandayo ◽  
...  
Keyword(s):  
Chemical Vapor Deposition ◽  
Growth Kinetics ◽  
Vapor Deposition ◽  
Chemical Vapor ◽  
Kinetics Analysis ◽  
Deposition Parameters ◽  
Kinetics Of

Impact of deposition parameters, microstructure and growth kinetics analysis of ZnO grown by Aerosol-assisted Chemical Vapor Deposition (AACVD).

Deposition and Crystallisation Behaviour of Amorphous Silicon Thin Films Obtained by Pyrolysis of Disilane Gas at Very Low Pressure

1994 ◽  
Vol 345 ◽  
Author(s):  
T. Kretz ◽  
D. Pribat ◽  
P. Legagneux ◽  
F. Plais ◽  
O. Huet ◽  
...  
Keyword(s):  
Activation Energy ◽  
Growth Rate ◽  
Amorphous Silicon ◽  
Vapor Deposition ◽  
Electrical Conductance ◽  
Chemical Vapor ◽  
Crystalline Fraction ◽  
Silicon Thin Films ◽  
Crystallisation Behaviour

AbstractHigh purity amorphous silicon layers were obtained by ultrahigh vacuum (millitorr range) chemical vapor deposition (UHVCVD) from disilane gas. The crystalline fraction of the films was monitored by in situ electrical conductance measurements performed during isothermal annealings. The experimental conductance curves were fitted with an analytical expression, from which the characteristic crystallisation time, tc, was extracted. Using the activation energy for the growth rate extracted from our previous work, we were able to determine the activation energy for the nucleation rate for the analysed-films. For the films including small crystallites we have obtained En ∼ 2.8 eV, compared to En ∼ 3.7 eV for the completely amorphous ones.

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