Effects of Impurities on the Kinetics of Nucleation and Growth in Amorphous Silicon

1986 ◽  
Vol 74 ◽  
Author(s):  
J. A. Roth ◽  
G. L. Olson
Keyword(s):  
Nucleation Rate ◽  
Solid Phase ◽  
Nucleation And Growth ◽  
Crystallization Time ◽  
Crystallite Growth ◽  
Impurity Effects ◽  
Time Resolved ◽  
Uniform Distributions ◽  
Amorphous Si ◽  
Kinetics Of

AbstractThe effects of intentionally introduced impurities on the crystallization time, nucleation rate and crystallite growth velocity during solid phase random crystallization of amorphous Si thin films have been determined. Films deposited in UHV onto oxidized Si wafers were subjected to multiple energy ion implantation to introduce uniform distributions of P, B, As, O or F at 0.1–1.0 at.%. Crystallization times and growth velocities were determined over the temperature range 650 to 850°C from time-resolved reflectivity measurements, and nucleation rates were determined from these data using a classical, steady state nucleation and growth model. Strong impurity effects are observed: P, B and As all decrease the nucleation rate but accelerate the growth of crystallites, whereas both 0 and F retard growth while enhancing nucleation. The largest effects are for P, which reduces the nucleation rate more than 100 times at 1% concentration, and F, which increases the rate by roughly the same amount.

Kinetics of Intrinsic and Dopant-Enhanced Solid Phase Epitaxy in Buried Amorphous Si Layers

1996 ◽  
Vol 439 ◽  
Author(s):  
J. C. McCallum
Keyword(s):  
Ion Implantation ◽  
Dopant Concentration ◽  
Solid Phase ◽  
Solid Phase Epitaxy ◽  
Entire Concentration Range ◽  
Time Resolved ◽  
Amorphous Si ◽  
First Time ◽  
Kinetics Of ◽  
Suitable Environment

AbstractThe kinetics of intrinsic and dopant-enhanced solid phase epitaxy (SPE) have been measured in buried amorphous Si (a-Si) layers produced by ion implantation. Buried a-Si layers formed by self-ion implantation provide a suitable environment for studies of the intrinsic growth kinetics of amorphous Si, free from the rate-retarding effects of H. For the first time, dopant-enhanced SPE rates have been measured under these H-free conditions. Buried a-Si layers containing uniform As concentration profiles ranging from 1–16.1 × 1019 As.cm−3 were produced by multiple-energy ion implantation and time resolved reflectivity was used to measure SPE rates over the temperature range 480–660°C. In contrast to earlier studies, the dopant-enhanced SPE rate is found to depend linearly on the As concentration over the entire concentration range measured. The SPE rate can be expressed in the form, v/vi(T) = 1 + N/[No exp(-ΔE/kT)], where vi(T) is the intrinsic SPE rate, N is the dopant concentration and No = 1.2 × 1021 cm−3, ΔE = 0.21 eV.

Kinetics of Intrinsic and Dopant-Enhanced Solid Phase Epitaxy in Buried Amorphous Si Layers

1996 ◽  
Vol 438 ◽  
Author(s):  
J. C. McCallum
Keyword(s):  
Ion Implantation ◽  
Dopant Concentration ◽  
Solid Phase ◽  
Solid Phase Epitaxy ◽  
Entire Concentration Range ◽  
Time Resolved ◽  
Amorphous Si ◽  
First Time ◽  
Kinetics Of ◽  
Suitable Environment

AbstractThe kinetics of intrinsic and dopant-enhanced solid phase epitaxy (SPE) have been measured in buried amorphous Si (a-Si) layers produced by ion implantation. Buried a-Si layers formed by self-ion implantation provide a suitable environment for studies of the intrinsic growth kinetics of amorphous Si, free from the rate-retarding effects of H. For the first time, dopant-enhanced SPE rates have been measured under these H-free conditions. Buried a- Si layers containing uniform As concentration profiles ranging from 1–16.1 × 1019 As.cm-3 were produced by multiple-energy ion implantation and time resolved reflectivi[ty was used to measure SPE rates over the temperature range 480–660°C. In contrast to earlier studies, the dopant-enhanced SPE rate is found to depend linearly on the As concentration over the entire concentration range measured. The SPE rate can be expressed in the form, v/vi(T) = 1 + N/[No exp(−Λ E/kT)], where vi(T) is the intrinsic SPE rate, N is the dopant concentration and No = 1.2 × 1021 cm-3, ΔE = 0.21 eV.

Kinetics of solid phase epitaxy in thick amorphous Si layers formed by MeV ion implantation

1990 ◽  
Vol 57 (13) ◽  
pp. 1340-1342 ◽  
Author(s):  
J. A. Roth ◽  
G. L. Olson ◽  
D. C. Jacobson ◽  
J. M. Poate
Keyword(s):  
Ion Implantation ◽  
Solid Phase ◽  
Solid Phase Epitaxy ◽  
Amorphous Si ◽  
Kinetics Of

Copper-Enhanced Solid Phase Crystallization of Amorphous Silicon Films

1996 ◽  
Vol 424 ◽  
Author(s):  
Dong Kyun Sohn ◽  
Dae Gyu Moon ◽  
Byung Tae Ahn
Keyword(s):  
Solid Phase ◽  
Copper Ions ◽  
Crystallization Time ◽  
Solid Phase Crystallization ◽  
New Process ◽  
Low Temperature Crystallization ◽  
Amorphous Si ◽  
Si Films ◽  
Fractal Size ◽  
Temperature Crystallization

AbstractLow-temperature crystallization of amorphous Si (a-Si) films was investigated by adsorbing copper ions on the surface of the films. The copper ions were adsorbed by spincoating of Cu solution. This new process lowered the crystallization temperature and reduced crystallization time of a-Si films. For 1000 ppm solution, the a-Si film was partly crystallized down to 500°C in 20 h and almost completely crystallized at 530°C in 20 h. The adsorbed Cu on the surface acted as a seed of crystalline and caused fractal growth. The fractal size was varied from 10 to 200 prm, depending on the Cu concentration in solution. But the grain size of the films was about 400 nm, which was similar to that of intrinsic films crystallized at 600°C.

Crystallization Kinetics of Fe-DOPED A1203

1994 ◽  
Vol 357 ◽  
Author(s):  
Todd W. Simpson ◽  
Ian V. Mitchell ◽  
Ning Yu ◽  
Michael Nastasi ◽  
Paul C. Mcintyre
Keyword(s):  
Crystallization Kinetics ◽  
Annealing Temperature ◽  
Rutherford Backscattering Spectrometry ◽  
Solid Phase ◽  
Solid Phase Epitaxy ◽  
Time Resolved ◽  
Α Phase ◽  
Kinetics Of ◽  
Beam Deposition

AbstractTime resolved optical reflectivity (TRR) and Rutherford backscattering spectrometry (RBS) and ion channelling methods have been applied to determine the crystallization kinetics of Fe-doped A1203 in the temperature range of 900-1050°C. Amorphous A1203 films, approximately 250 nm thick and with Fe cation concentrations of 0, 1.85, 2.2 and 4.5%, were formed by e-beam deposition on single crystal, [0001] oriented, A1203 substrates. Annealing was performed under an oxygen ambient in a conventional tube furnace, and the optical changes which accompany crystallization were monitored, in situ, by TRR with a 633nm wavelength laser.Crystallization is observed to proceed via solid phase epitaxy. An intermediate, epitaxial phase of -γ-Al203 is formed before the samples reach the ultimate annealing temperature. The 5% Fe-doped film transforms from γ to α-A1203 at a rate approximately 10 times that of the pure A1203 film and the 1.85% and 2.2% Fe-doped films transform at rates between these two extremes. The Fe-dopants occupy substitional lattice sites in the epilayer. Each of the four sets of specimens displays an activation energy in the range 5.0±0.2eV for the γ,α phase transition.

Nucleation and growth kinetics of preferred C54 TiSi2 orientations: time-resolved x-ray diffraction measurements

2002 ◽  
Vol 92 (9) ◽  
pp. 5189-5195 ◽  
Author(s):  
A. S. Özcan ◽  
K. F. Ludwig ◽  
C. Lavoie ◽  
C. Cabral ◽  
J. M. E. Harper ◽  
...  
Keyword(s):  
Growth Kinetics ◽  
Nucleation And Growth ◽  
X Ray Diffraction ◽  
Time Resolved ◽  
X Ray ◽  
Kinetics Of

Regrowth of Implanted–Amorphous Si

1986 ◽  
Vol 71 ◽  
Author(s):  
P. Ling ◽  
N.R. Wu ◽  
J. Washburn
Keyword(s):  
Activation Energy ◽  
Energy Dependence ◽  
Nucleation And Growth ◽  
Orientation Effect ◽  
Two Dimensional ◽  
Dimensional Model ◽  
Impurity Effects ◽  
Substrate Orientation ◽  
Two Dimensional Model ◽  
Amorphous Si

AbstractA two dimensional model of nucleation and growth is described which is consistent with the following experimental phenomena observed in the regrowth of ion-implanted silicon: (1) Substrate orientation effect on regrowth kinetics. (2) Impurity effects on regrowth kinetics. (3) The activation energy dependence of regrowth rate. (4) Impurity redistribution and supersaturation effect.

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