Cryo-Implantation Technology for Controlling Defects and impurity out diffusion

2000 ◽  
Vol 610 ◽  
Author(s):  
Atsushi Murakoshi ◽  
Kyoichi Suguro ◽  
Masao Iwase ◽  
Mitsuhiro Tomita ◽  
Katsuya Okumura
Keyword(s):  
Ion Implantation ◽  
Substrate Temperature ◽  
Single Crystal ◽  
Room Temperature ◽  
Amorphous Layer ◽  
Junction Depth ◽  
Si Substrate ◽  
Enhanced Diffusion ◽  
Pn Junction ◽  
Order Of Magnitude

AbstractWe propose a novel process module by using cryo-implantation and rapid thermal annealing (RTA). Boron or arsenic ions were implanted into a 8 inch (100) Si substrate which was cooled by using liquid nitrogen. The substrate temperature was controlled to be below at -160°C during ion implantation. It was found that an amorphous layer was formed by boron or arsenic implantation and the amorphous layer was completely recovered to a single crystal after annealing at 900°C for 30sec. No dislocation was observed in the implanted layer. It was also found that the thermal diffusion of boron was suppressed by cryo-implantation. PN junction depth was found to be about 10-20% shallower than that of room temperature implantation. These results suggest that transient enhanced diffusion of boron can be reduced by suppressing vacancy migration toward the surface during implantation. Cryo-implantation was found to be very effective in reducing defects and PN junction leakage was successfully reduced by one order of magnitude as compared with room temperature implantation.

AFM Study of Surface Morphology of Aluminum Nitride Thin Films

1995 ◽  
Vol 388 ◽  
Author(s):  
Yoshihisa Watanabe ◽  
Yoshikazu Nakamura ◽  
Shigekazu Hirayama ◽  
Yuusaku Naota
Keyword(s):  
Thin Films ◽  
Surface Morphology ◽  
Substrate Temperature ◽  
Single Crystal ◽  
Room Temperature ◽  
Ion Beam ◽  
Soda Lime ◽  
Silicon Single Crystal ◽  
Soda Lime Glass ◽  
Average Roughness

AbstractAluminum nitride (AlN) thin films have been synthesized by ion-beam assisted deposition method. Film deposition has been performed on the substrates of silicon single crystal, soda-lime glass and alumin A. the influence of the substrate roughness on the film roughness is studied. the substrate temperature has been kept at room temperature and 473K and the kinetic energy of the incident nitrogen ion beam and the deposition rate have been fixed to 0.5 keV and 0.07 nm/s, respectively. the microstructure of the synthesized films has been examined by X-ray diffraction (XRD) and the surface morphology has been observed by atomic force microscopy(AFM). IN the XRD patterns of films synthesized at both room temperature and 473K, the diffraction line indicating the alN (10*0) can be discerned and the broad peak composed of two lines indicating the a1N (00*2) and a1N (10*1) planes is also observed. aFM observations for 100 nm films reveal that (1) the surface of the films synthesized on the silicon single crystal and soda-lime glass substrates is uniform and smooth on the nanometer scale, (2) the average roughness of the films synthesized on the alumina substrate is similar to that of the substrate, suggesting the evaluation of the average roughness of the film itself is difficult in the case of the rough substrate, and (3) the average roughness increases with increasing the substrate temperature.

scholarly journals Measurements of the Diffusion of Iron and Carbon in Single Crystal NiAl using Ion Implantation and Secondary Ion Mass Spectrometry

1998 ◽  
Vol 527 ◽  
Author(s):  
R. J. Hanrahan ◽  
S. P. Withrow ◽  
M. Puga-Lambers
Keyword(s):  
Mass Spectrometry ◽  
Ion Implantation ◽  
Single Crystal ◽  
Secondary Ion Mass Spectrometry ◽  
Tracer Diffusion ◽  
Dynamic Strain ◽  
Enhanced Diffusion ◽  
Ion Mass Spectrometry ◽  
Impurity Elements ◽  
Secondary Ion

ABSTRACTClassical diffusion measurements in intermetallic compounds are often complicated by low diffusivities or low solubilities of the elements of interest. Using secondary ion mass spectrometry for measurements over a relatively shallow spatial range may be used to solve the problem of low diffusivity. In order to simultaneously obtain measurements on important impurity elements with low solubilities we have used ion implantation to supersaturate a narrow layer near the surface. Single crystal NiAl was implanted with either 12C or both 56Fe and 12C in order to investigate the measurement of substitutional (Fe) versus interstitial (C) tracer diffusion and the cross effect of both substitutional and interstitial diffusion. When C alone was implanted negligible diffusion was observed over the range of times and temperatures investigated. When both Fe and C were implanted together significantly enhanced diffusion of the C was observed, which is apparently associated with the movement of Fe. This supports one theory of dynamic strain aging in Fe alloyed NiAl.

Formation of Buried Tisi2 Layers in Single Crystal Silicon by Ion Implantion

1987 ◽  
Vol 107 ◽  
Author(s):  
P. Madakson ◽  
G.J. Clark ◽  
F.K. Legoues ◽  
F.M. d'Heurle ◽  
J.E.E. Baglin
Keyword(s):  
Ion Implantation ◽  
Single Crystal ◽  
Room Temperature ◽  
Single Crystal Silicon ◽  
Crystal Silicon ◽  
Buried Layers

Buried TiSi2 layers, about 600Å thick and 900Å below the surface, were formed in < 111> silicon by ion implantation. The implantation was done with either 120 or 170 keV Ti+ to doses ranging from 5 x 1016 to 2 x 1017 ions/cm2, and at temperatures of between ambient and 650° C. Annealing was done at 600° C, 700°C and 1000°C. Continuous buried layers were achieved only with samples implanted with doses equal or greater than 1017 ions/cm2 and at temperatures above 450°C. Below this dose TiSi2, was present only as discrete precipitates. For room temperature implants, the TiSi2, layer is formed on the surface. The damage present consists of dispersed TiSi6 precipitates and microtwins.

scholarly journals Growth of (110) GaAs/GaAs by Molecular Beam Epitaxy

1985 ◽  
Vol 46 ◽  
Author(s):  
L.T. Parechanian ◽  
E.R. Weber ◽  
T.L. Hierl
Keyword(s):  
Molecular Beam Epitaxy ◽  
Substrate Temperature ◽  
Hall Effect ◽  
Room Temperature ◽  
Molecular Beam ◽  
Defect Density ◽  
Temperature Dependent ◽  
Mbe Growth ◽  
Order Of Magnitude ◽  
Hall Effect Measurements

AbstractThe simultaneous molecular beam epitaxy (MBE) growth of (100) and (110) GaAs/GaAsintentionally doped with Si(∼lE16/cm^3) was studied as a function of substrate temperature, arsenic overpressure, and epitaxial growth rate. The films wereanalyzed by scanning electron and optical microscopy, liquid helium photoluminescence (PL), and electronic characterization.For the (110) epitaxal layers, an increase in morphological defect density and degradation of PL signal was observed with a lowering of the substrate temperature from 570C. Capacitance-voltage (CV) and Hall Effect measurements yield room temperature donor concentrations for the (100) films of n∼l5/cm^3 while the (110) layers exhibit electron concentrations of n∼2El7/cm^3. Hall measurements at 77K on the (100) films show the expected mobility enhancement of Si donors, whereas the (110) epi layers become insulating or greatly compensated. This behavior suggests that room temperature conduction in the (110) films is due to a deeper donor partially compensated by an acceptor level whose concentration is of the same order of magnitude as that of any electrically active Si. Temperature dependent Hall effect indicates that the activation energy of the deeper donor level lies ∼290 meV from the conduction band. PL and Hall effect indicate that the better quality (110) material is grown by increasingthe arsenic flux during MBE growth. The nature of the defects involved with the growth process will be discussed.

A Comparison of Low Energy BF2 Implantation in Si and Ge Preamorphized Silicon

1988 ◽  
Vol 128 ◽  
Author(s):  
Gary A. Ruggles ◽  
Shin-Nam Hong ◽  
Jimmie J. Wortman ◽  
Mehmet Ozturk ◽  
Edward R. Myers ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Crystalline Silicon ◽  
Amorphous Layer ◽  
Low Energy ◽  
Electrical Activation ◽  
Silicon Substrates ◽  
Boron Diffusion ◽  
Junction Depth ◽  
Rapid Thermal Anneal ◽  
Boron Segregation

ABSTRACTLow energy (6 keV) BF2 implantation was carried out using single crystal, Ge-preamorphized, and Si-preamorphized silicon substrates. Implanted substrates were rapid thermal annealed at temperatures from 600°C to 1050'C and boron channeling, diffusion, and activation were studied. Ge and Si preamorphization energies were chosen to produce nearly identical amorphous layer depths as determined by TEM micrographs (approximately 40 nm in both cases). Boron segregation to the end-of-range damage region was observed for 6 keV BF2 implantation into crystalline silicon, although none was detected in preamorphized substrates. Junction depths as shallow as 50 nm were obtained. In this ultra-low energy regime for ion implantation, boron diffusion was found to be as important as boron channeling in determining the junction depth, and thus, preamorphization does not result in a significant reduction in junction depth. However, the formation of junctions shallower than 100 rmu appears to require RTA temperatures below 1000°C which can lead to incomplete activation unless the substrate has been preamorphized. In the case of preamorphized samples, Hall measurements revealed that nearly complete electrical activation can be obtained for preamorphized samples after a 10 second rapid thermal anneal at temperatures as low as 600°C.

Junction Depth Reduction of ion Implanted Boron in Silicon Through Fluorine ion Implantation

2000 ◽  
Vol 610 ◽  
Author(s):  
L. S. Robertson ◽  
P. N. Warnes ◽  
K. S. Jones ◽  
S. K. Earles ◽  
M. E. Law ◽  
...  
Keyword(s):  
Ion Implantation ◽  
Secondary Ion Mass Spectrometry ◽  
Chemical Species ◽  
Amorphous Layer ◽  
Experimental Conditions ◽  
Enhanced Diffusion ◽  
Transient Enhanced Diffusion ◽  
Transmission Electron ◽  
Species Effect ◽  
Boron Diffusivity

AbstractThe interaction between boron and excess silicon interstitials caused by ion implantation hinders the formation of ultra-shallow, low resistivity junctions. Previous studies have shown that fluorine reduces boron transient enhanced diffusion, however it is unclear whether this observed phenomenon is due to the fluorine interacting with the boron atoms or silicon self-interstitials. Amorphization of a n-type Czochralski wafer was achieved with a 70 keV Si+ implantation at a dose of 1×1015/cm2. The Si+ implant produced a 1500Å deep amorphous layer, which was then implanted with 1.12 keV 1×1015/cm2 B+. The samples were then implanted with a dose of 2×1015/cm2F+ at various energies ranging from 2 keV to 36 keV. Ellipsometry measurements showed no increase in the amorphous layer thickness from either the boron or fluorine implants. The experimental conditions allowed the chemical species effect to be studied independent of the implant damage caused by the fluorine implant. Post-implantation anneals were performed in a tube furnace at 750° C. Secondary ion mass spectrometry was used to monitor the dopant diffusion after annealing. Transmission electron microscopy (TEM) was used to study the end-of-range defect evolution. The addition of fluorine reduces the boron transient enhanced diffusion for all fluorine energies. It was observed that both the magnitude of the boron diffusivity and the concentration gradient of the boron profile vary as a function of fluorine energy.

Solid krypton in MgO

1992 ◽  
Vol 7 (12) ◽  
pp. 3171-3174 ◽  
Author(s):  
M. Grant Norton ◽  
C. Barry Carter ◽  
Elizabeth L. Fleischer ◽  
James W. Mayer
Keyword(s):  
High Pressure ◽  
Electron Diffraction ◽  
Ion Implantation ◽  
Single Crystal ◽  
Magnesium Oxide ◽  
Room Temperature ◽  
Noble Gas ◽  
Lattice Parameter ◽  
Solid Krypton ◽  
Measured Lattice Parameter

Recent work by the authors has been extended to demonstrate the formation of solid krypton in single-crystal magnesium oxide. The solid inclusions, which were formed by ion implantation at room temperature, have been identified by electron diffraction. The formation of solid noble gas inclusions at room temperature indicates that they were under a high pressure. This pressure was determined, based on the measured lattice parameter, to be 1.7 GPa.

scholarly journals Синтез методом молекулярно-пучковой эпитаксии и свойства наноструктур InGaN разветвленной морфологии на кремниевой подложке

2019 ◽  
Vol 45 (21) ◽  
pp. 48
Author(s):  
Р.Р. Резник ◽  
К.П. Котляр ◽  
Н.В. Крыжановская ◽  
С.В. Морозов ◽  
Г.Э. Цырлин
Keyword(s):  
Substrate Temperature ◽  
Photoluminescence Spectrum ◽  
Room Temperature ◽  
Si Substrate ◽  
Mbe Growth ◽  
Morphological Studies

A possibility of InGaN «nanoflowers» MBE growth on Si substrate has been demonstrated. The results of morphological studies have shown that InGaN synthesis occurs in several stages even at constant substrate temperature. The grown structures show wide photoluminescence spectrum in the range from 450 to 950 nm at room temperature.

Enhanced Boron Diffusion in Amorphous Silicon

2004 ◽  
Vol 810 ◽  
Author(s):  
J.M. Jacques ◽  
N. Burbure ◽  
K.S. Jones ◽  
M.E. Law ◽  
L.S. Robertson ◽  
...  
Keyword(s):  
Amorphous Silicon ◽  
Room Temperature ◽  
Solid Phase ◽  
Amorphous Layer ◽  
Boron Diffusion ◽  
Cross Sectional ◽  
Enhanced Diffusion ◽  
Transmission Electron ◽  
Variable Angle Spectroscopic Ellipsometry ◽  
Secondary Ion

ABSTRACTIn prior works, we demonstrated the phenomenon of fluorine-enhanced boron diffusion within self-amorphized silicon. Present studies address the process dependencies of low temperature boron motion within ion implanted materials utilizing a germanium amorphization. Silicon wafers were preamorphized with either 60 keV or 80 keV Ge+ at a dose of 1×1015 atoms/cm2. Subsequent 500 eV, 1×1015 atoms/cm211B+ implants, as well as 6 keV F+ implants with doses ranging from 1×1014 atoms/cm2 to 5×1015 atoms/cm2 were also done. Furnace anneals were conducted at 550°C for 10 minutes under an inert N2 ambient. Secondary Ion Mass Spectroscopy (SIMS) was utilized to characterize the occurrence of boron diffusion within amorphous silicon at room temperature, as well as during the Solid Phase Epitaxial Regrowth (SPER) process. Amorphous layer depths were verified through Cross-Sectional Transmission Electron Microscopy (XTEM) and Variable Angle Spectroscopic Ellipsometry (VASE). Boron motion within as-implanted samples is observed at fluorine concentrations greater than 1×1020 atoms/cm3. The magnitude of the boron motion scales with increasing fluorine dose and concentration. During the initial stages of SPER, boron was observed to diffuse irrespective of the co-implanted fluorine dose. Fluorine enhanced diffusion at room temperature does not appear to follow the same process as the enhanced diffusion observed during the regrowth process.

Mechanism of Enhanced Diffusion of Aluminum in 6H-SiC in the Process of High-Temperature Ion Implantation

1997 ◽  
Vol 504 ◽  
Author(s):  
Igor O. Usov ◽  
A. A. Suvorova ◽  
V. V. Sokolov ◽  
Y. A. Kudryavtsev ◽  
A. V. Suvorov
Keyword(s):  
Mass Spectrometry ◽  
Diffusion Coefficient ◽  
High Temperature ◽  
Ion Implantation ◽  
Room Temperature ◽  
Secondary Ion Mass Spectrometry ◽  
Diffusion Mechanism ◽  
Enhanced Diffusion ◽  
Sic Wafer ◽  
Secondary Ion

ABSTRACTThe diffusion of Al in 6H-SiC during high-temperature ion implantation was studied using secondary ion mass spectrometry. A 6H-SiC wafer was implanted with 50 keV Al ions to a dose of 1.4E16 cm−2 in the high temperature range 1300°–1800TC and at room temperature. There are two diffusion regions that can be identified in the Al profiles. At high Al concentrations the gettering related peak and profile broadening are observed. At low Al concentrations, the profiles have a sharp kink and deep penetrating diffusion tails. In the first region, the diffusion coefficient is temperature independent, while in the second it exponentially increases as a function of temperature. The Al redistribution can be explained with the substitutional-interstitial diffusion mechanism.

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