Role of Oxygen Precipitation Processes in Defect Formation and Evolution in Oxygen Implanted Silicon-on-Insulator Material

1992 ◽  
Vol 279 ◽  
Author(s):  
J. C. Park ◽  
J. D. Lee ◽  
D. Venables ◽  
S. Krause ◽  
P. Roitman
Keyword(s):  
Defect Formation ◽  
Silicon On Insulator ◽  
Oxide Interface ◽  
Oxygen Precipitation ◽  
Transmission Electron ◽  
Precipitation Processes ◽  
Formation And Evolution ◽  
Similar Density ◽  
Single Implant

ABSTRACTThe role of precipitation processes in defect development in high temperature implanted single and multiple implant/anneal SIMOX was studied by transmission electron microscopy. The differences in defect type, density and location were compared. The dominant defects in single implanted and annealed material are pairs of narrow stacking faults (NSFs) at a density of ∼ 106 cm−2 while stacking fault pyramids (SFPs) at a similar density dominate multiple implant/anneal material. However, SFPs are confined to the buried oxide interface and thus the density of through-thickness defects is about two orders of magnitude lower in multiple implant (<104 cm−2) than in single implant material (∼106 cm−2). SFPs are formed from a collection of four NSFs pinned to residual oxide precipitates. This transformation is energetically possible only below a critical NSF length which is dictated by the relative location of the residual precipitates. In turn, the residual precipitate location is determined by the location of as-implanted defects on which SiO2 preferentially nucleates and grows. Thus, the synergistic interaction between precipitation and defect formation and evolution processes plays a key role in determining the final defect microstructure of SIMOX.

The Effect of Oxide Trenches on Defect Formation and Evolution in Ion-Implanted Silicon

2004 ◽  
Vol 810 ◽  
Author(s):  
Nina Burbure ◽  
Kevin S. Jones
Keyword(s):  
Silicon Oxide ◽  
Defect Formation ◽  
Solid Phase ◽  
Amorphous Layer ◽  
Oxide Interface ◽  
Cross Sectional ◽  
Patterned Wafers ◽  
Edge Defects ◽  
Formation And Evolution ◽  
Spike Anneal

ABSTRACTPattern induced defects during advanced CMOS processing can lead to lower quality devices with high leakage currents. Within this study, the effects of oxide trenches on implant related defect formation and evolution in silicon patterned wafers is examined. Oxide filled trenches approximately 4000Å deep were patterned into 300 mm <100> silicon wafers. Patterning was followed by ion implantation of Si+ at energies ranging from 10 to 80 keV. Samples were amorphized with doses of 1×1015 atoms/cm2, 5×1015 atoms/cm2, and 1×1016 atoms/cm2. Two independent repeating structures were studied. The first structure is comprised of silicon oxide filled trench lines, 3.7μm wide spaced 12.5μm apart, while the second structure contains silicon squares, 0.6μm on a side, surrounded by a silicon oxide filled trench. Cross- sectional and planar view transmission electron microscopy (TEM) samples were used to examine the defect morphology after annealing at temperatures ranging from 700°C to 950°C and at times between 1 second and 1 minute. Following complete regrowth, an array of defects was observed to form near the surface at the silicon/silicon oxide interface. These trench edge defects appeared to nucleate at the amorphous-crystalline interface for all energies and doses studied. Upon a spike anneal at 700°C, it was observed that regrowth of the amorphous layer had completed except in the region near the trench edge. Thus, it is believed that this defect results from the pinning of the amorphous-crystalline interface along the trench edge during solid phase epitaxial regrowth (SPER).

The Role of Stress on the Shape of the Amorphous-Crystalline Interface and Mask-Edge Defect Formation in Ion-Implanted Silicon

2004 ◽  
Vol 810 ◽  
Author(s):  
Carrie E. Ross ◽  
Kevin S. Jones
Keyword(s):  
Defect Formation ◽  
Region Of Interest ◽  
Amorphous Layer ◽  
Uniaxial Tensile ◽  
Cross Sectional ◽  
Transmission Electron ◽  
Patterned Structures ◽  
Uniaxial Tensile Stress ◽  
Mask Edge

ABSTRACTStress is known to affect the regrowth velocities during recrystallization of an amorphous layer. This study investigates how the stress from patterned structures alters regrowth and in turn affects defect formation. Prior to patterning, 80Å SiO2 and 1540Å of silicon nitride were deposited on a 200 mm [001] silicon wafer. A 40keV Si+ amorphizing implant at a dose of 1×1015 atoms/cm2 was then performed into the patterned wafer. The regrowth of the amorphous layer along the mask edge was studied by partially recrystallizing the layer for various times at 550°C both with the mask present and after etching off the oxide and nitride pads. A significant number of cross-sectional Transmission Electron Microscopy (TEM) samples were prepared and imaged. It was found that the stress from the patterned structures enhances the vertical and lateral regrowth velocities, as well as alters the shape of the amorphous-crystalline interface during regrowth. Previous studies have shown that uniaxial tensile stress increases the regrowth velocity. Simulations show that the region of interest in these samples is under tensile stresses, suggesting that this type of stress should accelerate the regrowth velocity. In addition dislocation half loops are observed to form along the mask edge for certain structures. The nucleation of these defects is suppressed by the presence of the film. The relationship between the stress from the patterned structures, the regrowth of the amorphous layer, and the formation of dislocation half-loops along the mask edge will be discussed.

Oxygen bubble formation and evolution during oxygen implantation and annealing of silicon-on-insulator material

1991 ◽  
Vol 49 ◽  
pp. 864-865
Author(s):  
S J. Krause ◽  
J.D. Lee ◽  
B.L. Chen ◽  
S. Seraphin ◽  
B. Cordts ◽  
...  
Keyword(s):  
Structural Changes ◽  
Bubble Formation ◽  
Silicon Layer ◽  
Surface Region ◽  
Silicon On Insulator ◽  
High Dose ◽  
Oxygen Implantation ◽  
Transmission Electron ◽  
Formation And Evolution ◽  
Radiation Hard

Silicon-on-insulator (SOI) material fabricated by high dose oxygen implantation (SIMOX) is a material increasingly used for higher speed and radiation hard circuits. During implantation a variety of structural changes occur, including the formation of defects, bubbles, precipitates, and the buried oxide layer. The topic of bubble formation and evolution has received only limited study. Sjoreen et al. first reported the presence of spherical, randomly distributed precipitates near the top surface of the silicon layer. El-Ghor et al. further examined these precipitates and proposed that they were cavities filled with oxygen. Maszara confirmed the presence of spheroids filled with oxygen in the silicon top surface region in the 1mA cm-2 as-implanted samples. In this work, transmission electron microscopy (TEM) techniques were used to investigate the effect of implantation conditions on the bubble formation and the effect of subsequent annealing conditions on the evolution of bubbles.

Transmission Electron Microscope Studies of O, C, N Precipitation in Crystalline Silicon

1985 ◽  
Vol 59 ◽  
Author(s):  
A. Bourret
Keyword(s):  
Crystalline Silicon ◽  
Annealing Treatment ◽  
High Resolution Electron Microscopy ◽  
Czochralski Silicon ◽  
Oxygen Precipitation ◽  
Transmission Electron ◽  
Resolution Electron ◽  
One Step ◽  
Precipitation Phenomena

ABSTRACTThe understanding of the precipitation phenomena of light non dopant Impurities has been recently improved thanks to high resolution electron microscopy and microanalysis. After a one-step annealing in Czochralski silicon long coesite (SIO2) ribbons are formed between 485° and 750°C; amorphous platelets (SIOx with x =1. 2 to 2) are formed between 650°C -1050°C. Silicon Interstitlals generated during the precipitation partly relax the strain energy associated with the volume change. These Interstltlals are also able to precipitate In various forms. After a two-step annealing both platelets and/or octahedra containing amorphous SIOx are formed. The role of carbon on oxygen precipitation Is important: It changes the nucleation parameters and gives a retardation phenomena In a two-step annealing treatment. Similar phenomena are observed in oxygen implanted silicon. The nucleation and growth process able to explain these observations is far from being well understood. The SIO2 polymorphism, the Important role of SI Interstitials and the mutual attraction between oxygen and carbon are some of the ingredients which explain this complexity.

Bound Exciton Energies, Biaxial Strains, and Defect Microstructures in GaN/AlN/6H-SiC(0001) Heterostructures

1996 ◽  
Vol 449 ◽  
Author(s):  
W. G. Perry ◽  
T. Zheleva ◽  
K. J. Linthicum ◽  
M. D. Bremser ◽  
R. F. Davis ◽  
...  
Keyword(s):  
Defect Formation ◽  
Lattice Mismatch ◽  
Compressive Strain ◽  
Lattice Parameter ◽  
Buffer Layers ◽  
Film Stress ◽  
Thermal Expansion Coefficients ◽  
Transmission Electron ◽  
Defect Microstructures

ABSTRACTBiaxial strains resulting from mismatches in thermal expansion coefficients and lattice parameters in 22 GaN films grown on A1N buffer layers previously deposited on vicinal and on-axis 6H-SiC(0001) substrates were measured via changes in the c-axis lattice parameter (c). Six of the films were in compression, indicating the residual strain due to lattice mismatch was not relieved. A Poisson's ratio of v=0.18 was calculated. The bound exciton energy (EBx) was a linear function of these strains. The shift in EBx with film stress was 23 meV/GPa. The role of the SiC off-axis tilt was investigated for GaN films grown concurrently on the vicinal and on-axis 6H-SiC substrates. Marked variations in EBx and c were observed, with a maximum shift of ΔEBx = 15 meV and Δc = 0.0042 Å. Threading dislocations densities of ~1010/cm2 and ~108/cm2 were determined for GaN films grown on vicinal and on-axis SiC, respectively. A 0.9% residual compressive strain at the GaN/AIN interface was observed by high resolution transmission electron microscopy (HRTEM). It is proposed that the on-axis SiC substrate does not offer a sufficient density of steps for defect formation to relieve the lattice mismatch between GaN and A1N and A1N and SiC.

scholarly journals Defects and gas sensing properties of carbon nanotube-based devices

2015 ◽  
Vol 4 (1) ◽  
pp. 25-30 ◽  
Author(s):  
S. Baldo ◽  
V. Scuderi ◽  
L. Tripodi ◽  
A. La Magna ◽  
S.G. Leonardi ◽  
...  
Keyword(s):  
Carbon Nanotube ◽  
Defect Formation ◽  
Gas Sensing ◽  
Field Effect Transistors ◽  
Arc Discharge ◽  
Chemical Vapour ◽  
Raman Analysis ◽  
Sensing Applications ◽  
Transmission Electron

Abstract. In this work we report on the development of back-gated carbon nanotube-field effect transistors (CNT-FETs), with CNT layers playing the role of the channel, and on their electrical characterisation for sensing applications. The CNTs have been deposited by electrophoresis on an interdigitated electrode region created on a SiO2/Si substrate. Different kinds of CNTs have been used (MWCNTs by arc discharge in liquid nitrogen and MWCNTs by chemical vapour deposition, CVD) and the electrical characterisation of the devices was performed in a NH3- and NO2-controlled environment. Preliminary data have shown an increase in the channel resistance under NH3 exposure, whereas a decrease is observed after exposure to NO2, and the sensitivity to each gas depends on the kind of CNTs used for the device. Furthermore, the defect formation by Si ion implantation on CNTs was investigated by high-resolution transmission electron microscopy (TEM) and Raman analysis. The behaviour observed for the different devices can be explained in terms of the interaction between structural or chemical defects in CNTs and the gas molecules.

In-Situ Observations of Dislocation Patterning in Deformed Polycrystalline Aluminum

2008 ◽  
Author(s):  
Peri Landau ◽  
Roni Z. Shneck ◽  
Guy Makov ◽  
Arie Venkert
Keyword(s):  
Tensile Tests ◽  
Dislocation Motion ◽  
Polycrystalline Aluminum ◽  
Transmission Electron ◽  
Formation And Evolution ◽  
In Situ Observations ◽  
Dislocation Walls

The formation and evolution of dislocation patterns in pure polycrystalline aluminum was examined using transmission electron microscopy. The conventional characterization of the deformed samples was combined with in-situ tensile tests of prestrained samples which were carried out in order to get a better understanding of dislocation motion during deformation. The role of different types of boundaries was studied and it was found that while dense dislocation walls have an ordered structure since they are geometrically necessary, incidental dislocation boundaries can change their configuration from tangled to ordered.

On Future Directions in Pathology

1982 ◽  
Vol 40 ◽  
pp. 274-277
Author(s):  
Benjamin F. Trump ◽  
Irene K. Berezesky ◽  
Raymond T. Jones
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
Clinical Pathology ◽  
Future Directions ◽  
Diagnostic Pathology ◽  
The Past ◽  
Transmission Electron ◽  
Organ Systems ◽  
The Many

The role of electron microscopy and associated techniques is assured in diagnostic pathology. At the present time, most of the progress has been made on tissues examined by transmission electron microscopy (TEM) and correlated with light microscopy (LM) and by cytochemistry using both plastic and paraffin-embedded materials. As mentioned elsewhere in this symposium, this has revolutionized many fields of pathology including diagnostic, anatomic and clinical pathology. It began with the kidney; however, it has now been extended to most other organ systems and to tumor diagnosis in general. The results of the past few years tend to indicate the future directions and needs of this expanding field. Now, in addition to routine EM, pathologists have access to the many newly developed methods and instruments mentioned below which should aid considerably not only in diagnostic pathology but in investigative pathology as well.

Transmission Electron Microscopy studies of texture of Cr underlayer of magnetic recording hard disk

1991 ◽  
Vol 49 ◽  
pp. 580-581
Author(s):  
L. Tang ◽  
G. Thomas ◽  
M. R. Khan ◽  
S. L. Duan
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Magnetic Recording ◽  
Magnetic Thin Films ◽  
Magnetic Films ◽  
Substrate Bias ◽  
Epitaxial Relationship ◽  
Transmission Electron

Cr thin films are often used as underlayers for Co alloy magnetic thin films, such as Co1, CoNi2, and CoNiCr3, for high density longitudinal magnetic recording. It is belived that the role of the Cr underlayer is to control the growth and texture of the Co alloy magnetic thin films, and, then, to increase the in plane coercivity of the films. Although many epitaxial relationship between the Cr underlayer and the magnetic films, such as ﹛1010﹜Co/ {110﹜Cr4, ﹛2110﹜Co/ ﹛001﹜Cr5, ﹛0002﹜Co/﹛110﹜Cr6, have been suggested and appear to be related to the Cr thickness, the texture of the Cr underlayer itself is still not understood very well. In this study, the texture of a 2000 Å thick Cr underlayer on Nip/Al substrate for thin films of (Co75Ni25)1-xTix dc-sputtered with - 200 V substrate bias is investigated by electron microscopy.

Transmission Electron Microscopy of Evaporated Perylene Thin Films

1990 ◽  
Vol 48 (2) ◽  
pp. 336-337
Author(s):  
C. Ewins ◽  
J.R. Fryer
Keyword(s):  
Electron Microscopy ◽  
Thin Films ◽  
Transmission Electron Microscopy ◽  
Molecular Electronics ◽  
High Vacuum ◽  
Amorphous Layer ◽  
Electric Heater ◽  
Transmission Electron ◽  
Polycyclic Aromatic

The preparation of thin films of organic molecules is currently receiving much attention because of the need to produce good quality thin films for molecular electronics. We have produced thin films of the polycyclic aromatic, perylene C10H12 by evaporation under high vacuum onto a potassium chloride (KCl) substrate. The role of substrate temperature in determining the morphology and crystallography of the films was then investigated by transmission electron microscopy (TEM).The substrate studied was the (001) face of a freshly cleaved crystal of KCl. The temperature of the KCl was controlled by an electric heater or a cold finger. The KCl was heated to 200°C under a vacuum of 10-6 torr and allowed to cool to the desired temperature. The perylene was then evaporated over a period of one minute from a molybdenum boat at a distance of 10cm from the KCl. The perylene thin film was then backed with an amorphous layer of carbon and floated onto copper microscope grids.

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