scholarly journals Metal induced crystallization of amorphous silicon for photovoltaic solar cells

2011 ◽  
Vol 11 ◽  
pp. 196-199 ◽  
Author(s):  
D. Van Gestel ◽  
I. Gordon ◽  
J. Poortmans
Keyword(s):  
Solar Cells ◽  
Amorphous Silicon ◽  
Metal Induced Crystallization ◽  
Photovoltaic Solar Cells ◽  
Induced Crystallization

Optimization of the metal/silicon ratio on nickel assisted crystallization of amorphous silicon

2005 ◽  
Vol 869 ◽  
Author(s):  
L. Pereira ◽  
M. Beckers ◽  
R.M.S. Martins ◽  
E. Fortunato ◽  
R. Martins
Keyword(s):  
Amorphous Silicon ◽  
Spectroscopic Ellipsometry ◽  
Crystallization Time ◽  
Crystalline Fraction ◽  
Nickel Metal ◽  
Metal Induced Crystallization ◽  
Structural Improvement ◽  
Short Annealing ◽  
The One ◽  
Induced Crystallization

AbstractThe aim of this work is to optimize the metal/silicon ratio on nickel metal induced crystallization of silicon. For this purpose amorphous silicon layers with 80, 125 and 220 nm thick were used on the top of which 0.5 nm of Ni was deposited and annealed during the required time to full crystallize the a-Si. The data show that the 80 nm a-Si layer reaches a crystalline fraction of 95.7% (as detected by spectroscopic ellipsometry) after annealed for only 2 hours. No significant structural improvement is detected by ellipsometry neither by XRD when annealing the films for longer times. However, on 125 nm thick samples, after annealing for 2 hours the crystalline fraction is only 59.7%, reaching a similar value to the one with 80 nm only after 5 hours, with a crystalline fraction of 92.2%. Here again no significant improvements were achieved by using longer annealing times. Finally, the 220 nm thick a-Si sample is completely crystallized only after 10 hours annealing. These data clear suggest that the crystallization of thicker a-Si layers requires thicker Ni films to be effective for short annealing times. A direct dependence of the crystallization time on the metal/silicon ratio was observed and estimated.

Analytical Studies of the Capping Layer Effect on Aluminum Induced Crystallization of Amorphous Silicon

2006 ◽  
Vol 910 ◽  
Author(s):  
Husam Abu-Safe ◽  
Abul-Khair M. Sajjadul-Islam ◽  
Hameed A. Naseem ◽  
William D. Brown
Keyword(s):  
Amorphous Silicon ◽  
Layer Structure ◽  
Silicon Layer ◽  
Nodule Formation ◽  
Capping Layer ◽  
X Ray ◽  
Metal Induced Crystallization ◽  
Layer Effect ◽  
Polysilicon Films ◽  
Induced Crystallization

AbstractThe effect of capping layer on metal induced crystallization of amorphous silicon was studied. Three sets of samples were prepared in this study. All samples had the basic layer structure of amorphous silicon layer deposited on a glass substrate. This was followed by a thin aluminum layer deposition. The second and third sets, however, had a third layer of amorphous silicon with thicknesses of 20 and 50 nm, respectively. These layers were deposited on top of the aluminum. The samples were annealed at 400°C for 15, 30 and 45 minutes. The crystallization fraction in the resultant films was analyzed using X-Ray diffraction, scanning electron microscopy, energy dispersive x-ray spectroscopy, and atomic force microscopy. It was observed that the capping layer reduces nodule formation improving the smoothness of the crystallized polysilicon films.

Thin-film polycrystalline-silicon solar cells on high-temperature glass based on aluminum-induced crystallization of amorphous silicon

2006 ◽  
Vol 910 ◽  
Author(s):  
Dries Van Gestel ◽  
Ivan Gordon ◽  
Lode Carnel ◽  
Linda R. Pinckney ◽  
Alexandre Mayolet ◽  
...  
Keyword(s):  
Thin Film ◽  
Solar Cells ◽  
High Temperature ◽  
Amorphous Silicon ◽  
Polycrystalline Silicon ◽  
Open Circuit ◽  
Si Solar Cells ◽  
Induced Crystallization ◽  
Seed Layers ◽  
Aluminum Induced Crystallization

AbstractEfficient thin-film polycrystalline-silicon (pc-Si) solar cells on foreign substrates could lower the price of photovoltaic electricity. Aluminum-induced crystallization (AIC) of amorphous silicon followed by epitaxial thickening at high temperatures seems a good way to obtain efficient pc-Si solar cells. Due to its transparency and low cost, glass is well suited as substrate for pc-Si cells. However, most glass substrates do not withstand temperatures around 1000°C that are needed for high-temperature epitaxial growth. In this paper we investigate the use of experimental transparent glass-ceramics with high strain-point temperatures as substrates for pc-Si solar cells. AIC seed layers made on these substrates showed in-plane grain sizes up to 16 μm. Columnar growth was observed on these seed layers during high-temperature epitaxy. First pc-Si solar cells made on glass-ceramic substrates in substrate configuration showed efficiencies up to 4.5%, fill factors up to 75% and open-circuit voltage (Voc) values up to 536 mV. This is the highest Voc reported for pc-Si solar cells on glass and the best cell efficiency reported for cells made by AIC on glass.

Metal induced crystallization of amorphous silicon

1987 ◽  
Vol 5 (4) ◽  
pp. 1447-1450 ◽  
Author(s):  
A. E. Robertson ◽  
L. G. Hultman ◽  
H. T. G. Hentzell ◽  
S.‐E. Hörnström ◽  
G. Shaofang ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Metal Induced Crystallization ◽  
Induced Crystallization

Directional Field Aided Lateral Crystallization of Amorphous Silicon Thin Films

2001 ◽  
Vol 664 ◽  
Author(s):  
Marek A. T. Izmajlowicz ◽  
Neil A. Morrison ◽  
Andrew J. Flewitt ◽  
William I. Milne
Keyword(s):  
Thin Films ◽  
Low Temperature ◽  
Electric Field ◽  
Amorphous Silicon ◽  
Solid Phase ◽  
Excimer Laser Annealing ◽  
Solid Phase Crystallization ◽  
Metal Induced Crystallization ◽  
Silicon Thin Films ◽  
Induced Crystallization

ABSTRACTFor application to active matrix liquid crystal displays (AMLCDs), a low temperature (< 600 °C) process for the production of polycrystalline silicon is required to permit the use of inexpensive glass substrates. This would allow the integration of drive electronics onto the display panel. Current low temperature processes include excimer laser annealing, which requires expensive equipment, and solid phase crystallization, which requires high temperatures. It is known that by adding small amounts of metals such as nickel to the amorphous silicon the solid phase crystallization temperature can be significantly reduced. The rate of this solid phase metal induced crystallization is increased in the presence of an electric field. Previous work on field aided crystallization has reported crystal growth that either proceeds towards the positive terminal or is independent of the direction of the electric field. In this work, extensive investigation has consistently revealed directional crystallization, from the positive to the negative terminal, of amorphous silicon thin films during heat treatment in the presence of an electric field. This is the first time that this phenomenon has been reported. Models have been proposed for metal induced crystallization with and without an applied electric field in which a reaction between Ni and Si to produce NiSi is the rate-limiting step. The crystallization rate is increased in the presence of an electric field through the drift of positive Ni ions.

Sign in / Sign up

Export Citation Format

Share Document