A Multiphysics Peridynamic Model for Simulation of Fracture in Si Thin Films during Lithiation/Delithiation Cycles

Material failure is the main obstacle in fulfilling the potential of electrodes in lithium batteries. To date, different failure phenomena observed experimentally in various structures have become challenging to model in numerical simulations. Moreover, their mechanisms are not well understood. To fill the gap, here we develop a coupled chemo-mechanical model based on peridynamics, a particle method that is suitable for simulating spontaneous crack growth, to solve the fracture problems in silicon thin films due to lithiation/delithiation. The model solves mechanical and lithium diffusion problems, respectively, and uses a coupling technique to deal with the interaction between them. The numerical examples of different types of Si films show the advantage of the model in this category and well reproduce the fracture patterns observed in the experiments, demonstrating that it is a promising tool in simulating material failure in electrodes.

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Crystallization of Amorphous Silicon Thin Films by Microwave Heating

MRS Proceedings ◽

10.1557/opl.2014.920 ◽

2014 ◽

Vol 1666 ◽

Cited By ~ 1

Author(s):

Tomohiko Nakamura ◽

Shinya Yoshidomi ◽

Masahiko Hasumi ◽

Toshiyuki Sameshima ◽

Tomohisa Mizuno

Keyword(s):

Thin Films ◽

Heat Treatment ◽

Amorphous Silicon ◽

Microwave Heating ◽

Volume Ratio ◽

Heated Sample ◽

Silicon Thin Films ◽

Scattering Spectra ◽

Raman Scattering Spectra ◽

Si Films

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.

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¼c Silicon Thin Films Deposited by Remote Plasma Enhanced Chemical Vapor Deposition Process

MRS Proceedings ◽

10.1557/proc-192-535 ◽

1990 ◽

Vol 192 ◽

Cited By ~ 5

Author(s):

C. Wang ◽

G. N. Parsons ◽

S. S. Kim ◽

E. C. Buehler ◽

R. J. Nemanich ◽

...

Keyword(s):

Thin Films ◽

Chemical Vapor ◽

Deposition Process ◽

Substrate Material ◽

Degree Of Crystallinity ◽

Silicon Thin Films ◽

Hydrogen Dilution ◽

Type C ◽

Si Films ◽

P Type

ABSTRACTIn an earlier study, we deposited ¼c-Si thin films by reactive magnetron sputtering (RMS). Here we extend our studies to the deposition of both undoped and high conductivity N-type and P-type ¼c-Si thin films by a remote PECVD. We show that ¼c-Si films can be deposited by bringing hydrogen, H2, into the source gas mixtures. The H2 could introduced by either upstream in a He/H2 mixture and directly plasma excited, or downstream, and be remotely excited along with the silane, SiH4, feed gas. The degree of crystallinity is shown to depend on the hydrogen dilution, the substrate temperature and the substrate material.

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A Study on the Metal Induced Lateral Crystallization Behavior of Amorphous Silicon Thin Films

MRS Proceedings ◽

10.1557/proc-441-101 ◽

1996 ◽

Vol 441 ◽

Cited By ~ 1

Author(s):

Byung-Il Lee ◽

Kwang-Ho Kim ◽

Won-Cheol Jeong ◽

Pyung-Su Ahn ◽

Jin-Wook Shin ◽

...

Keyword(s):

Thin Films ◽

Amorphous Silicon ◽

Crystallization Behavior ◽

Crystallization Rate ◽

External Stress ◽

Tem Analysis ◽

Silicon Thin Films ◽

Amorphous Si ◽

Lateral Crystallization ◽

Si Films

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.

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Poly-Si films with long carrier lifetime prepared by rapid thermal annealing of Cat-CVD amorphous silicon thin films

Thin Solid Films ◽

10.1016/j.tsf.2007.06.216 ◽

2008 ◽

Vol 516 (5) ◽

pp. 600-603 ◽

Cited By ~ 4

Author(s):

Keisuke Ohdaira ◽

Yuki Abe ◽

Makoto Fukuda ◽

Shogo Nishizaki ◽

Noritaka Usami ◽

...

Keyword(s):

Thin Films ◽

Amorphous Silicon ◽

Thermal Annealing ◽

Rapid Thermal Annealing ◽

Carrier Lifetime ◽

Silicon Thin Films ◽

Si Films

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Silicide Mediated Grown Silicon Thin Films for Photodiodes

MRS Proceedings ◽

10.1557/proc-0974-cc01-12 ◽

2006 ◽

Vol 974 ◽

Author(s):

Joondong Kim ◽

Wayne A. Anderson ◽

Chang-Soo Han ◽

Eung-Sug Lee

Keyword(s):

Thin Films ◽

Silicon Thin Films ◽

Metal Induced Growth ◽

Si Films ◽

Si Wafer

ABSTRACTQuality Si thin films were grown by the metal-induced growth (MIG) method. Metal (Co, Ni, or mixing of Co and Ni) was thermally evaporated on a 200 nm-SiO2 coated Si wafer. Si sputtering was performed at 600 – 620 °C in a dc magnetron system. The reaction of Si and metal first formed a silicide (CoSi2 or NiSi2) layer and further Si sputtering grew a Si film above it. The grown Si films were practically fabricated for Schottky photodiodes and electrically measured under one sun scan illumination (100 mW/cm2).

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Effect of Deposition Condition of Precursor Amorphous Silicon Thin Films on the Behavior of Milc

MRS Proceedings ◽

10.1557/proc-685-d3.3.1 ◽

2001 ◽

Vol 685 ◽

Author(s):

Y.-G. Yoon ◽

G.-B. Kim ◽

H.-H Park ◽

S.-W Lee ◽

S.-K. Joo

Keyword(s):

Thin Films ◽

Vapor Deposition ◽

Deposition Temperature ◽

Structural Changes ◽

Chemical Vapor ◽

Deposition Condition ◽

Micro Structure ◽

Silicon Thin Films ◽

Lower Temperature ◽

Si Films

AbstractWe studied on the effect of a deposition condition of precursor a-Si thin films on the shape and micro-structure of MILC. The a-Si thin films were prepared by Plasma Enhanced Chemical Vapor Deposition (PECVD) with silane and hydrogen as a source gas and the deposition temperature was varied from 100 to 400∼. The a-Si films deposited at a lower temperature showed a tendency to (111) crystals and leaving some a-Si residues in MILC region, while those with higher deposition temperature tended to be crystallized to (110). These differences were explained in terms of original hydrogen content and following structural changes by the dehydrogenation during annealing.

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Diffusion of Arsenic and Phosphorus in Laserprocessed-Polycrystalline-Silicon-Thin-Films

MRS Proceedings ◽

10.1557/proc-5-311 ◽

1981 ◽

Vol 5 ◽

Cited By ~ 2

Author(s):

H. Baumgart ◽

H. J. Leamy ◽

L. E. Trimble ◽

C. J. Doherty ◽

G. K. Celler

Keyword(s):

Thin Films ◽

Grain Boundary ◽

Boundary Diffusion ◽

Diffusion Length ◽

Grain Boundary Diffusion ◽

Silicon Thin Films ◽

P Diffusion ◽

Ion Laser ◽

Si Films

ABSTRACTGrain boundary diffusion of arsenic and phosphorus in laser processed polycrystalline Si films has been investigated. Mesa diodes were fabricated in LPCVD Si thin films on SiO2 and subsequently recrystallized by cw Ar ion laser processing to form large grain material. The diffusion length of enhanced As and P diffusion along grain boundaries intersecting the p-n junction has been measured by the EBIC technique. Quantitative experimentation allowed determination of the grain boundary diffusion coefficients of As and P in the temperature range from 900°C to 1250°C.

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Hydrogen Configurations in Microcrystallized Sputtered Amorphous Silicon.

MRS Proceedings ◽

10.1557/proc-283-531 ◽

1992 ◽

Vol 283 ◽

Cited By ~ 1

Author(s):

L. Lusson ◽

P. Elkaim ◽

M. Cuniot ◽

D. Ballutaud ◽

R. Rizk ◽

...

Keyword(s):

Thin Films ◽

Amorphous Silicon ◽

Molecular Hydrogen ◽

Film Growth ◽

Amorphous Film ◽

Microcrystalline Silicon ◽

Silicon Thin Films ◽

Si Films ◽

Small Clusters ◽

Secondary Ion

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.

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SILICON THIN FILMS PREPARED BY PECVD USING VHF POWER IN A CIRCULAR-PARALLEL-PLATE PLASMA REACTOR

International Journal of Modern Physics B ◽

10.1142/s0217979210056517 ◽

2010 ◽

Vol 24 (22) ◽

pp. 4209-4216 ◽

Cited By ~ 1

Author(s):

SHUTANG WEN ◽

YU MIAO ◽

YUNHUI WANG ◽

LIWEI ZHANG ◽

JINGXIAO LU ◽

...

Keyword(s):

Thin Films ◽

Deposition Rate ◽

Plasma Reactor ◽

Excitation Frequency ◽

Pulse Frequency ◽

Pulsed Power ◽

Silicon Thin Films ◽

Deposition Parameters ◽

Si Films ◽

Highly Uniform

The deposition rate of μc-Si films was investigated for four excitation frequencies 30, 40, 60, 70 and 80 MHz with other deposition parameters fixed. Deposition rate increases with the increasing of excitation frequency, while Raman crystallinity behaves more complicated. With the optimization of deposition parameters, p-i-n solar cells at an initial efficiency of 5.41% were fabricated. With the increasing of plasma excitation frequency, the non-uniformity of these thin films increases. To better understand the cause of the non-uniformity of these films, a numerical simulation was carried out. The numerical results generally followed the experimental data. It turned out that the standing waves and the evanescent wave guide modes on the electrode surface played an important role. In order to achieve highly uniform thin films, a triode-electrode was employed together with a pulsed power source. We found that with a proper choice of pulse frequency and DC voltage applied to the mesh, non-uniformity is less than 8% for films deposited on 10×10 cm 2 substrates. Simulations were also applied to analyze the results.

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Prevention of Thin Film Failures for PECVD Amorphous-Si on Plastic Substrate

Solid State Phenomena ◽

10.4028/www.scientific.net/ssp.124-126.387 ◽

2007 ◽

Vol 124-126 ◽

pp. 387-390

Author(s):

Jong Hyun Seo ◽

Jae Hong Jeon ◽

Hee Hwan Choe

Keyword(s):

Thin Film ◽

Thin Films ◽

Failure Process ◽

Thin Film Deposition ◽

Film Deposition ◽

Plastic Substrate ◽

Plastic Films ◽

Silicon Thin Films ◽

Si Films ◽

Griffith’S Theory

Amorphous silicon thin films were deposited below 160oC on PES plastic films using PECVD. After thin film deposition using PECVD, thin film failures such as film delamination and cracking often occurred. For successful growth of thin films (about 2000 Å) without their failures, it is necessary to solve the critical problem related to the internal compressive stress (some GPa) leading to delamination at a threshold thickness value of the films. The Griffith’s theory explains the failure process by looking at the excess of elastic energy inside the film, which overcomes the cohesive energy between film and substrate. In this work, reducing a-Si layer film thickness and optimizing a barrier SiNx layer have produced stable a-Si films at 150oC, over PES substrates.

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