Hydrogen Configurations in Microcrystallized Sputtered Amorphous Silicon.

1992 ◽  
Vol 283 ◽  
Author(s):  
L. Lusson ◽  
P. Elkaim ◽  
M. Cuniot ◽  
D. Ballutaud ◽  
R. Rizk ◽  
...  

ABSTRACTSuccessive deuterium diffusion and effusion experiments are performed on undoped microcrystalline silicon obtained from thermally crystallized sputtered amorphous silicon thin films. The effect of prior incorporation of deuterium during the amorphous film growth on the crystallization mechanism and on the microcrystalline film quality is probed by the use of the post hydrogenation procedure. In connection with the deuterium solubility as provided by secondary ion mass spectroscopy (SIMS) profiling, the analysis of the effusion spectra suggests the existence of large cavities in the crystallized a-Si:D films, containing most probably molecular hydrogen. They are absent in the corresponding crystallized non-deuterated a-Si films. Other deuterium configurations seem to be present in both kinds of samples such as weakly bonded deuterium in small clusters and at grain boundaries.

2014 ◽  
Vol 1666 ◽  
Author(s):  
Tomohiko Nakamura ◽  
Shinya Yoshidomi ◽  
Masahiko Hasumi ◽  
Toshiyuki Sameshima ◽  
Tomohisa Mizuno

ABSTRACTWe report crystallization of amorphous silicon (a-Si) thin films and improvement of thin film transistors (TFTs) characteristics using 2.45 GHz microwave heating assisted with carbon powders. Undoped 50-nm-thick a-Si films were formed on quartz substrates and heated by microwave irradiation for 2, 3, and 4 min. Raman scattering spectra revealed that the crystalline volume ratio increased to 0.42 for the 4-min heated sample. The dark and photo electrical conductivities measured by Air mass 1.5 at 100 mW/cm2 were 2.6x10-6 and 5.2x10-6 S/cm in the case of 4-min microwave heating followed by 1.3x106-Pa-H2O vapor heat treatment at 260°C for 3 h. N channel polycrystalline silicon TFTs characteristics were improved by the combination of microwave heating with high-pressure H2O vapor heat treatment. The threshold voltage decreased from 5.3 to 4.2 V and the effective carrier mobility increased from 18 to 25 cm2/Vs.


1996 ◽  
Vol 441 ◽  
Author(s):  
Byung-Il Lee ◽  
Kwang-Ho Kim ◽  
Won-Cheol Jeong ◽  
Pyung-Su Ahn ◽  
Jin-Wook Shin ◽  
...  

AbstractBasic mechanisms for both Ni- and Pd-metal induced lateral crystallization (MILC) are investigated. For both cases, tiny silicides were formed under the metal deposited area, and propagated toward amorphous Si films leaving crystallized Si behind at temperatures as low as 500 °C. Ni-MILC was influenced by Pd such that the lateral crystallization rate was enhanced, and the temperature for the lateral crystallization was lowered to 450 °C. Through TEM analysis and external stress experiments, it was found that the enhancement of the lateral crystallization rate was closely related to the compressive stress generated by the formation of nearby Pd2Si.


2009 ◽  
Vol 80 (7) ◽  
Author(s):  
Fatiha Kail ◽  
Jordi Farjas ◽  
Pere Roura ◽  
Pere Roca i Cabarrocas

2008 ◽  
Vol 516 (5) ◽  
pp. 600-603 ◽  
Author(s):  
Keisuke Ohdaira ◽  
Yuki Abe ◽  
Makoto Fukuda ◽  
Shogo Nishizaki ◽  
Noritaka Usami ◽  
...  

2013 ◽  
Vol 652-654 ◽  
pp. 1739-1742
Author(s):  
Xia Wu ◽  
Long Gu ◽  
Ji Sen Zhang ◽  
Hui Dong Yang

Microcrystalline silicon thin films were deposited on glass substrates by VHF-PECVD varying the ratio of hydrogen dilution from 88% to 98%. The structural characteristics, deposition rate and photosensitivity of the films were investigated. With the improvement of the hydrogen dilution ratio, crystallization rate of the films had been improved which was much more stable than amorphous silicon that the films transmit from amorphous silicon to microcrystalline silicon. However the deposition rate had been reduced with the increase of the hydrogen dilution and the highest deposition rate was 0.43nm/s. The samples showed a downward trend of photosensitivity with optical and dark conductivity both decreasing first then increasing. Thus suitable hydrogen dilution ratio should be chosen according to the different needs in preparation of microcrystalline silicon film.


2003 ◽  
Vol 762 ◽  
Author(s):  
Hwang Huh ◽  
Jung H. Shin

AbstractAmorphous silicon (a-Si) films prepared on oxidized silicon wafer were crystallized to a highly textured form using contact printing of rolled and annealed nickel tapes. Crystallization was achieved by first annealing the a-Si film in contact with patterned Ni tape at 600°C for 20 min in a flowing forming gas (90 % N2, 10 % H2) environment, then removing the Ni tape and further annealing the a-Si film in vacuum for2hrsat600°C. An array of crystalline regions with diameters of up to 20 μm could be formed. Electron microscopy indicates that the regions are essentially single-crystalline except for the presence of twins and/or type A-B formations, and that all regions have the same orientation in all 3 directions even when separated by more than hundreds of microns. High resolution TEM analysis shows that formation of such orientation-controlled, nearly single crystalline regions is due to formation of nearly single crystalline NiSi2 under the point of contact, which then acts as the template for silicide-induced lateral crystallization. Furthermore, the orientation relationship between Si grains and Ni tape is observed to be Si (110) || Ni (001)


2020 ◽  
Vol 2 (3) ◽  
Author(s):  
Lukas Terkowski ◽  
Iain W. Martin ◽  
Daniel Axmann ◽  
Malte Behrendsen ◽  
Felix Pein ◽  
...  

2020 ◽  
Vol 984 ◽  
pp. 91-96
Author(s):  
Cheng Liu ◽  
Yu Hao Song ◽  
Dong Yang Li ◽  
Wei Li

The structural and optical properties of amorphous silicon (a-Si) and Al-dispersed amorphous silicon (a-Si:Al) thin films irradiated by femtosecond (fs) laser at various energy densities are investigated comparatively in this article. It is found that there is an uneven crystallization in both amorphous thin films by means of optical microscopy and laser Raman spectroscopy respectively. The crystallization in each pulse spot area is gradually weakened from the center to the edge along with the energy dispersion of laser irradiation. The laser induced crystallization in a-Si thin films begins early and develops more extensively compared to that in a-Si:Al thin films, and Al nanoparticles inhibit somehow the crystallization of a-Si in a-Si:Al thin films.


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